This invention relates to fluoropolymer fibers and films which can be modified by cationic agents, such as cationic dyes. The fiber or film comprises a blend of a first and a second copolymer, or it comprises a terpolymer, the blend or terpolymer having (1) an acid or ionic functionality provided by a pendant group represented by the formula xe2x80x94(Oxe2x80x94CF2CFR)aOxe2x80x94CF2CFRxe2x80x2SO3xe2x88x92Z+, wherein R and Rxe2x80x2 are independently selected from F, Cl or a perfluorinated alkyl group having 1 to 10 carbon atoms, a=0, 1 or 2, and Z+ is H+, an alkali metal cation, or a cation derived from a compound selected from the group consisting of a cationic dye, a cationic whitener, a cationic flame retardant, a cationic antistatic agent, and mixtures thereof, and (2) a larger amount of a fluoroalkylvinylether, a fluoroalkene, or ethylene functionality. Such fibers and films are useful in various consumer goods where the product is desirably colored, whitened, antistatic, or flame retardant.

This invention relates to fluoropolymer fibers and films which are receptive to cationic modifying agents such as dyes, whiteners, antistatic agents, and flame retardants, and the fibers or films formed by treatment of the receptive fibers or films of the invention therewith. Such fibers and films are useful in various consumer goods where the products are desirably colored, whitened, antistatic or flame retardant.
Among the properties of fluoropolymers, especially perfluorinated polymers, which make them particularly useful are low friction, hydrophobicity, and chemical inertness. These very properties, however, conspire to make dyeing of fluoropolymers problematical since many dyeing processes involve aqueous baths and reactive dye sites. As a result of these problems, it has become common practice to color fluoropolymers using pigments.
In the area of fluoropolymer fibers, pigmentation must be accomplished in the melt prior to fiber spinning. The solid pigment particles have been found in practice to increase the wear on the high precision spinning equipment, while agglomeration of those particles interferes with polymer flow. Furthermore, in use, it is known that pigmented products may undesirably transfer pigmentation to surfaces in contact with them. Still further, pigmented fibers tend to have a dull appearance. Similar considerations apply to the fabrication of films or sheets by melt casting.
It has long been known in the art that polytetrafluoroethylene (PTFE) at molecular weights below ca. 1 million exhibits excessive brittleness for many practical uses. Thus, the most generally useful PTFE resins and products today have molecular weights in excess of 1 million, typically, 10 million, and though exhibiting a melting point, are not for any practical purpose thermoplastic.
It was found many years ago that a tough, lower molecular weight, melt processible copolymer can be made by copolymerizing tetrafluoroethylene (TFE) with various comonomers to form copolymers containing ca. 1-10 mol-% of a branched monomer unit. Among these comonomers are ethylene, hexafluoropropylene (HFP), and perfluoroalkyl vinyl ethers of the formula: CF2=CFxe2x80x94ORf, wherein Rf is a perfluoroalkyl group such as perfluoroethyl, perfluoropropyl, or perfluorobutyl.
It has long been known in the art to add sulfonate functionality to polyester and polyamide fibers to provide a reactive site for cationic dyes. Also known in the art are perfluoroalkoxy sulfonyls of the formula, CF2=CF(Rf)nxe2x80x94OCF2CF2SO2X, wherein Rf is a perfluoroalkyl or a perfluoroalkoxy group, n=0 or 1, and X is F or Cl. Perfluorinated copolymers of TFE and a perfluoroalkoxysulfonyl comonomer of the formula, CF2=CF[xe2x80x94OCF2CF(CF3)]nxe2x80x94OCF2CF2SO2F, wherein n is 0 or 1, and wherein the sulfonyl fluoride group has been hydrolyzed to the related sulfonic acid or sulfonate have long been in widespread commercial use as ion exchange membranes, such as NAFION(copyright) ion exchange membranes, available from DuPont. For many end uses, the sulfonyl moiety is converted into an acid or ionic form which is no longer melt processible but is receptive to cationic dyes. However, the ionic form of the comonomer is known to be highly hygroscopic, the physical properties of the resulting copolymer being highly dependent upon moisture content and exhibiting considerable deterioration at high moisture levels. At comonomer concentrations in the range needed to provide melt processibility, fibers produced from the cation-receptive hydrolyzed form of NAFION(copyright) are excessively moisture sensitive and thus not suitable for many potential applications.
Other copolymers of TFE, such as those derived from the copolymerization of TFE with a monomer containing an alkylvinylether pendant group may exhibit desirable physical properties and no sensitivity to moisture, but are not cation-receptive.
Connolly et al. (U.S. Pat. No. 3,282,875) disclose certain terpolymers of perfluoroalkoxysulfonyl halides, tetrafluoroethylene, and certain perfluoroalkylvinylethers or higher perfluoro olefins, and methods for their synthesis. However, the mole percents used in Connolly for the components of their terpolymers are designed to produce a cross-linked elastomer.
U.S. Pat. No. 3,692,569 (see Example IX) describes a PTFE yarn coated with a copolymer of tetrafluoroethylene and CF2=CFOCF2CF(CF3)OCF2CF2SO2F which is contacted with a solution of NaOH, followed by rinsing and dipping in dilute HCl and rinsing. The resultant yarn was said to be dyeable with xe2x80x9cSevronxe2x80x9d, a cationic dye.
What are needed therefore, are fluoropolymer fibers and films that are receptive to modifying agents such as dyes, whiteners, antistatic agents, and flame retardants, which retain their desirable physical and mechanical properties and which do not have the problems and deficiencies of the prior art.
The present invention provides a blend comprising a first copolymer and a second copolymer; said first copolymer comprising monomeric units of tetrafluoroethylene and a first comonomer selected from the group consisting of: a fluoroalkylvinylether, a fluoroalkene having at least 3 carbons, and ethylene; said second copolymer comprising monomeric units of tetrafluoroethylene and a second comonomer comprising a fluoroalkenyl radical having attached thereto a pendant group comprising a radical represented by the formula:
xe2x80x94(Oxe2x80x94CF2CFR)aOxe2x80x94CF2CFRxe2x80x2Q,
wherein:
R and Rxe2x80x2 are independently selected from F, Cl or a perfluorinated alkyl group having 1 to 10 carbon atoms;
a=0, 1 or 2;
Q is selected from the group consisting of: xe2x80x94SO3xe2x88x92Z+ and xe2x80x94SO2X;
Z+ is H+, an alkali metal cation, or a cation derived from a compound selected from the group consisting of: a cationic dye, a cationic whitener, a cationic flame retardant, a cationic antistatic agent, and mixtures thereof, and
X is F or Cl;
said first copolymer comprising about 0.5-20 mol-% of the first comonomer; said second copolymer comprising about 5-25 mol-% of the second comonomer; and said blend comprising about 1-10% by weight of said second copolymer. The present invention also provides a fiber or a film comprising such a blend.
The present invention further provides a terpolymer, comprising monomeric units of a first termonomer of tetrafluoroethylene; a second termonomer selected from the group consisting of: a fluoroalkylvinylether, a fluoroalkene having at least 3 carbons, and ethylene; and a third termonomer comprising a fluoroalkenyl radical having attached thereto a pendant group comprising a radical represented by the formula
xe2x80x94(Oxe2x80x94CF2CFR)aOxe2x80x94CF2CFRxe2x80x2Q,
wherein:
R and Rxe2x80x2 are independently selected from F, Cl, or a perfluorinated alkyl group having 1 to 10 carbon atoms;
a=0, 1 or 2;
Q is selected from the group consisting of: xe2x80x94SO3xe2x88x92Z+ and xe2x80x94SO2X;
Z+ is H+, an alkali metal cation, or a cation derived from a compound selected from the group consisting of: a cationic dye, a cationic whitener, a cationic flame retardant, a cationic antistatic agent, and mixtures thereof; and
X is F or Cl;
said terpolymer comprising about 0.5-5 mol-% of the second termonomer and about 0.1-2 mol-% of the third termonomer. The present invention also provides a fiber or a film comprising such a terpolymer.
The present invention further provides a process for producing a shaped article, the process comprising the steps of mixing a first copolymer and a second copolymer to form a mixture, said first copolymer comprising monomeric units of tetrafluoroethylene and a first comonomer selected from the group consisting of a fluoroalkylvinylether, a fluoroalkene having at least 3 carbons, and ethylene; and said second copolymer comprising monomeric units of tetrafluoroethylene and a second comonomer comprising a fluoroalkenyl radical having attached thereto a pendant group comprising a radical represented by the formula xe2x80x94(Oxe2x80x94CF2CFR)aOxe2x80x94CF2CFRxe2x80x2SO2X, wherein R and Rxe2x80x2 are independently selected from F, Cl or a perfluorinated alkyl group having 1 to 10 carbon atoms; a=0, 1 or 2; and X is F or Cl; said first copolymer comprising about 0.5-20 mol-% of the first comonomer, and said second copolymer comprising about 5-25% of said second comonomer; heating said first and second copolymers simultaneously with or subsequent to mixing, to a temperature sufficient to form a molten blend without significant degradation of either copolymer, said blend comprising about 1-10% by weight of said second copolymer; feeding the molten blend to a shaping device having at least one aperture, each aperture defined therein by a wall; and extruding the molten blend through the at least one aperture to form a shaped article. The present process may further comprise cooling the shaped article and contacting the shaped article with a solution comprising an alkali metal base to yield a cation-receptive shaped article, and may further comprise contacting the cation-receptive shaped article with a cationic modifying agent.
The present invention also provides a process for producing a shaped article, comprising the steps of extruding a composition comprising a molten terpolymer through at least one aperture of a shaping device to form a shaped article, each aperture defined by a wall within said device, said terpolymer comprising monomeric units of a first termonomer of tetrafluoroethylene; a second termonomer selected from the group consisting of a fluoroalkylvinylether, a fluoroalkene having at least 3 carbons, and ethylene; and a third termonomer comprising a fluoroalkenyl radical having attached thereto a pendant group comprising a radical represented by the formula xe2x80x94(Oxe2x80x94CF2CFR)aOxe2x80x94CF2CFRxe2x80x2SO2X, wherein R and Rxe2x80x2 are independently selected from F, Cl or a perfluorinated alkyl group having 1 to 10 carbon atoms, a=0, 1 or 2, and X is F or Cl; said terpolymer comprising about 0.5-5 mol-% of the second termonomer and about 0.1-2 mol-% of the third termonomer. The process may further comprise cooling the shaped article and contacting the shaped article with a solution comprising an alkali metal base to yield a cation-receptive shaped article, and may further comprise contacting the cation-receptive shaped article with a cationic modifying agent.


A semiconductor device includes a first interlayer insulating film formed on a semiconductor substrate; a second interlayer insulating film formed on the first interlayer film and including a plurality of grooves; a first barrier metal formed on inner surfaces of the grooves; a first interconnect part and a first bonding electrode part including a copper film formed on the first barrier metal; a second barrier metal formed on the first interconnect part and the first bonding electrode part; a second interconnect part including a metal film formed on the first interconnect part via the second barrier metal; a second bonding electrode part including a metal film formed on the first bonding electrode part via the second barrier metal; and a third interlayer insulating film formed on the second interlayer insulating film, the second interconnect part, and the second bonding electrode part, and including an opening that allows exposure of the surface of the second bonding electrode part.

1. Field of the Invention
The present invention relates to a semiconductor device and a fabrication method for the same.
2. Description of the Related Art
In recent years, along with miniaturization of LSIs, copper wires having low resistance (specific resistance is approximately 35% that of aluminum) and high electromigration tolerance are used as interconnect material for semiconductor devices since the sub-quarter micron age. Particularly, use of copper wires for the top layer interconnects required to carry a large current are very effective and are used for all multi-layered interconnects. However, copper is easily oxidized, and oxidation occurs not only in a hot atmosphere without a controlled oxygen concentration but also in atmospheric air. Once copper begins to oxidize, the oxidation continues deep into the copper without stopping at the surface, thereby corroding the entire copper interconnect. Therefore, in the case of bonding electrodes formed of copper wires, not only do the electrode surfaces become oxidized and lose adhesiveness with bonding wires, but corrosion of the oxidized electrodes due to interior oxidation progresses, and corrosion due to oxidation extends to the overall bonding wires and the copper wires.
As a result, when using copper as the interconnect material, technology for forming bonding electrodes using a material, instead of copper, that is resistant to oxidation is generally employed. FIG. 7 shows a conventional semiconductor device having bonding electrodes on top of copper wires. The bonding electrodes are made of a material resistant to oxidation (see Japanese Patent Application Laid-open No. 2003-31575 (p. 7, FIG. 7B), for example). The semiconductor device of FIG. 7 is formed through the processes described below. First, an interconnect pattern groove is formed in an insulating film 31 such as a silicon oxide film formed on a semiconductor substrate, a barrier metal 32 and a copper film 33 are deposited in the groove, and are then planarized using chemical mechanical polishing (CMP) so that only the copper film 33 remains in the groove. A diffusion preventive film 34 and an insulating film 35 such as a silicon oxide film are then deposited on the planarized area, forming an intermediate insulating film. An opening is formed in the diffusion preventive film 34 and the insulating film 35 or the intermediate insulating film so as to expose a part of the copper film 33.
Next, a barrier metal 36, which prevents a reaction from occurring between copper and aluminum, an aluminum film 37, and a barrier metal 38, which reduces reflectivity of the aluminum film 37 surface and allows lithography of an interconnect pattern, are successively deposited on the exposed part of the copper film and then removed through etching, except for a region in which a bonding electrode is supposed to be formed. Last, an insulating film 39 is deposited across the entirety and the insulating film 39 and the barrier metal 38 are selectively etched so as to expose the aluminum film 37, thereby forming a bonding opening 40 on top of the aluminum film 37. This completes the bonding electrode.
However, with the above invention, when the aluminum film is formed in the groove formed by etching the intermediate insulating film, there is a problem of poor coverage may occur ability since the groove is concave.
In order to improve this process, a semiconductor device has been manufactured in which a bonding electrode is formed by embedding a copper film in a groove formed in the intermediate insulating film layer to form a via, planarizing the top of the intermediate insulating film, depositing an aluminum film, and then etching.
However, with the two above-given processes of forming an aluminum film or a bonding electrode on such copper wires, cost has increased due to the fact that after the copper wires are formed, several additional processes such as forming an insulating film, a lithography process, and an etching process are necessary. Thus, the number of processes, until the bonding electrode is completed is increased.

Semiconductor device and fabrication method for the same


Intrusion by climbing or jumping over a fence can be detected, and intrusion is detected in a wide area without large-scale equipment. FBGs (grating sections) of different types having different refractive indexes of fiber glass are arranged at predetermined intervals in a longitudinal direction of optical fibers 12, 13A, and 13B, the optical fibers are laid down between poles on the top of a fence or a side thereof, reflected waves from the FBGs are issued by photodetection devices 14, 15A, and 15B in response to an optical input to the optical fibers, and a wavelength shift detection device 16 detects a position of an FBG which exhibits a wavelength shift by swinging of the optical fibers by a stress acting on the fence. A pattern recognition device 19 fetches positions of the wavelength-shifted FBGs as differences between timings of the pulse signals and discriminates swinging of the fence caused by intrusion from swinging of the fence caused by other factors on the basis of output patterns of the pulse signals.

1. Field of the Invention
The present invention relates to a break-in detection sensor for detecting intrusion into a building or premises by an optical fiber sensor and, more particularly to, a system in which an optical fiber detection sensor of an FBG type is laid down on a side of a fence or the top thereof to detect intrusion.
2. Description of the Related Art
In recent years, security against terrorism or illegal intrusion in airports, harbors, defense facilities, and other important places attracts attention. Various break-in detection apparatuses or break-in detection systems for detecting intrusion into buildings or premises are proposed and executed.
As detection sensors used in the apparatuses and systems of this type include a vibration sensor, an infra-red ray interception sensor, an electric field interception sensor, a mechanical tension sensor, and an abnormal state sensor for surveillance image obtained by a surveillance monitor are known. Furthermore, an optical fiber sensor using an optical fiber is proposed (for example, see Japanese Patent Application Laid-Open (JP-A) No. 2001-296111).
As surveillance systems operated in coordination with the detection sensors, a recording method of ITV camera images and remote monitoring, an image analysis method, a method using alarm generation by an alarm unit and wireless communication are known.
As other detection sensors using optical fibers, optical fiber detection sensors of an FBG (Fiber Brag Grating) type and an OTDR (Optical Time Domain Reflectometry) type are known.
FIG. 3 shows the principle of the FBG type fibro-optic detection sensor. As shown in FIG. 3, grating sections (FBG) 101 having different fiber glass refraction indexes are provided at predetermined intervals in longitudinal cross section through an optical fiber 100. The grating sections 101 resonate and reflect only components having the wavelength of two times the interval λL out of pulse lights coming from an optical signal generator 102. The thus reflected light has a wavelength shifted in proportion to stretch strain in the grating sections 101. The reflected light component is guided by a half mirror 103 through a narrow band variable filter 104 to a light receiver 105 for detection. By checking the degree of wavelength shifts (frequency shifts), it can be detected whether or not the stretch strain in the optical fiber exceeds a predetermined value. When this detection is executed, the positions of the grating sections 101 can be discriminated as positions of intrusion.
FIG. 4 explains the principle of an OTDR fiber-optic detection sensor. An optical fiber includes sections having different refraction factors. When light passes through the sections, the light is refracted and scattered due to the different refraction factors such that light rays having wave lengths equal to that of the incident light are reflected on an end of the optical fiber on which the light is incident. The OTDR fiber-optic detection sensor makes use of this Rayleigh scattering light, where a light pulse issued from a light pulse generator 106 is introduced into the optical fiber 107 before Rayleigh scattering light produced therein is guided out thereof via a half mirror 108 to be received by a receiver 109 where any optical fiber strain, displacement and disconnection points can be detected on the basis of the amount of light or the time required for reflection.
In the break-in detection apparatus using the FBG type fibro-optic detection sensor or the OTDR fibro-optic detection sensor, an optical fiber is laid down along a fence or a wall of premises or facilities to be detected to make it possible to detect intrusion. In particular, in the FBG type fibro-optic detection sensor, a plurality of FBGs having different reflection wavelengths are incorporated in a core section of one optical fiber to make it possible to simultaneously detect intrusion at a large number of positions.
This configuration has a structure in which FBG (Grating sections) 110A to 110N are incorporated in the core section of the optical fiber 110 at appropriate intervals and have different reflection wavelengths λ1, λ2, λ3, . . . . An optical signal generator 111 continuously or intermittently (pulsatively) generates an optical signal in a band including the reflection wavelengths held by the FBGs incorporated in the optical fiber 110. A half mirror 112 uses the optical signal from the optical signal generator 111 as an optical input to the optical fiber 110 to optically guide reflected lights from the FBGs of the optical fiber 110 to a narrow band variable filter 113. The narrow band variable filter 113 transmit the reflected waves from the FBGs at once to output these reflected waves to a photodetector 114. The photodetector 114 simultaneously converts the reflected waves into electric signals having equal frequencies or low frequencies obtained by multiplying the frequencies by 1/n. A wavelength shift detector 115 compares the frequency signals obtained by the photodetector 114 with a reference frequency signal from a reference frequency generator 116 to obtain pulse signals having timings sorted by reflection wavelengths the frequencies of which shift. An intrusion position determination section 117 determines a position of an FBG where a reflection wavelength shifts, i.e., an intrusion position on the basis of the timings of the pulse signals to obtain the output.


The invention provides a system for precisely guiding the direction of a drill bit. The drill shaft has an orientation sensor that detects deviation of the drilling direction from the desired direction; the drill bit is steerable by preferentially directing flushing fluid at the drilling end; and a fluid modulation means controls the flushing in response to a signal from the orientation sensor. The invention also provides a tiltmeter for detecting deviation from vertical of the axis of rotation of a rotating shaft. A gravity-driven mechanical oscillator, for instance a pendulum, is carried by the rotating shaft, and has a natural oscillation frequency matched to the rotational frequency of the shaft; and a sensor determines the phase relationship of the oscillator relative to the angular position of the shaft, thereby producing a signal indicating the deviation of the shaft from vertical.

The invention relates to systems for drilling into the surface of the earth, and in particular to such systems incorporating means to measure and guide the bit to the desired direction.
In nuclear weapons testing, the mining industry, and the oil industry, there is a need for guided drilling or coring. In the case of the mining and oil industries, a subsurface location containing a desirable resource sometimes needed to be reached by a hole that is as straight as possible (McCray, Arthur and Cole, Frank, Oil Well Drilling Technology, Norman: Univ. of Oklahoma Press, 1967; 306). A "straight" hole in this case is not only the shortest distance from the surface to the location of interest, but also is parallel to the local gravity vector. FIG. 1 illustrates what happens when a bit deviates from an ideally straight path. The bit starts at point A, and instead of going to the ideal point B, it ends at point C. The deviated point C defines the error in terms of the deviation angle .alpha., or the distance from the ideal endpoint .delta..
Hole deviation is caused by non-uniform formations and inclined rock strata, and in the case of a conventional bit, can be accelerated by the bending of the drill string. With a conventional bit, a hole is usually considered straight if the deviation angle .alpha. is less than 5 degrees.
In nuclear weapons testing the CORRTEX method is proposed to verify the strength of nuclear bomb blasts. This method involves drilling a straight hole near the bomb and inserting a tube or "core" in the hole. When the blast occurs, the core is crushed at a rate indicative of the blast strength (Norman C. "Test Ban Talks Reach Impasse (Seismic Detection vs. CORRTEX)." Science April 15, 1988; 273). The "straightness" requirement for this kind or hole is a deviation distance .delta. of 2 feet in a 2000 foot deep hole. The hole deviation angle .alpha. in this case is only 0.057 degrees.
Precise vertical drilling, in general, requires slow drilling rates so that the drilling assembly seeks the vertical. During a conventional vertical drilling, the drill steel is stopped in order to measure the orientation of the hole and determine the proper correction, only then the drilling is resumed. Some conventional steering methods require placing a metal wedge on the bottom of the hole to deflect the drill to the desired direction, or using a hydraulic piston pushing against the wall of the hole to deflect and re-orient the drill. Thus, this type of straight-hole vertical drilling is slow and also dependent on the geological conditions.
In summary, there is a need for a continuously guided drilling system which can operate at conventional drilling rates of tens of feet per hour or higher.


An audio power amplifier is provided that includes circuitry to prevent popping noises when the amplifier is turned on and turned off. The amplifier can be powered with a single-ended voltage power supply, and thus may be used within systems such as personal computer. The amplifier includes a control circuit that prevents the fast charging of the output AC coupling capacitor when the amplifier is turned on and turned off. The control circuit controls a driver stage such that the output transistors turn on slowly when power is first applied, and such that the output transistors turn off quickly when the supply voltage is removed.

1. Field of the Invention
The present invention relates to audio power amplifiers and more particularly to audio power amplifiers having single-ended power supplies.
2. Description of the Relevant Art
A variety of audio power amplifiers are well known in the art. When an audio power amplifier is used in a system having a single-ended power supply, such as a power supply providing a positive voltage with respect to ground and no negative voltage, the amplifier is typically designed with a push-pull configured output stage including a large AC coupling capacitor connected at the output terminal of the amplifier. The large AC coupling capacitor is included to maintain the DC output level at zero volts. Since an input signal provided to the power amplifier is level shifted to an average voltage which is intermediate between the positive supply and ground to allow the signal to vary between the supply voltages, the AC coupling capacitor blocks the intermediate DC voltage at the push-pull output stage to thereby provide an output signal with a zero volt DC level.
A problem associated with such audio power amplifiers is a loud popping noise generated by the amplifier at turn-on and turn-off. The popping noise generated by the amplifier is the result of the quick charging and discharging of the large AC coupling capacitor at turn-on and turn-off. An audio power amplifier that is not associated with this popping characteristic is desirable.

Audio power amplifier with noise prevention at turn-on and turn-off


A semiconductor device includes a substrate and a plurality of transistors arranged on the substrate in an array. The transistor includes a first electrode, a plurality of second electrodes, and a gate electrode. The second electrodes are arranged around the first electrode. The gate electrode is located between the first electrode and the second electrodes. The first electrode is a polygon. The gate electrode is around the first electrode, and an edge of the gate electrode facing the first electrode has a shape corresponding to that of the first electrode. The first electrode and the edge of the gate electrode facing the first electrode are regular polygons, and have the same center.

1. Field of the Invention
The present disclosure relates to a semiconductor device and, in particular, to a semiconductor device having transistors.
2. Description of the Related Art
For improving switching speed, conventional power supplies utilize field-effect transistors as switching devices. Further, field-effect transistors have lower resistance, and thus power efficiency is improved.
As shown in FIG. 1, conventional field-effect transistors A10 are arranged on a substrate A20. The field-effect transistors A10 are connected with each other in parallel to output greater current. Each of the field-effect transistors A10 includes a drain electrode A11, a source electrode A12, and a gate electrode A13. The drain electrode A11, the source electrode A12, and the gate electrode A13 are linear in structure and parallel to each other.
When the field-effect transistors A10 are installed in a high-voltage power supply with a voltage higher than 300V, the distance between the drain electrode A11 and the source electrode A12 is greater than 7 nm. However, in this structure, the sum of the gate width Wg of the gate electrode A13 on the substrate A20 is short, and the current outputting by the field-effect transistors A10 is smaller.
For increasing the gate width Wg, as shown in FIG. 2, the drain electrodes A21 and the source electrodes A22 of the field-effect transistors A20 are alternately arranged in an array. The drain electrodes A21 and the source electrodes A22 are squares, and the gate electrodes A23 are elongated rectangles around the source electrodes A22. However, since electrons flow along a shortest path in general, the electrons may not flow through the invalid areas Z1 in FIG. 2. Therefore, some areas in the substrate A20 are wasted. A greater area of the substrate A20 is needed to output the same current with the same numbers as the field-effect transistors A20, and as a result, manufacturing cost is increased.


A method, and a system of using the method, of controlling a motor having a rated capacity. The method includes determining the motor has been started, determining a plurality of operating parameters of the motor after the motor has started, determining a threshold from a portion of the operating parameters, comparing one of the determined operating parameters with the threshold, and operating the motor at a level corresponding to below the rated capacity when one of the determined operating parameters is greater than the threshold. When an electric motor having a control system according to the present invention lifts a load, drives a machine, or starts other motions, the control system automatically adjusts to a power level that corresponds to the load. In this way, the motor will not be allowed to exert any power or force to the load in excess of what is necessary. If the machine being driven becomes jammed, binds, or draws more power for some unexpected reason, the motor will be shut down to reduce or to limit damage to the load or the machine.

The invention relates to a controller for a motor, and particularly, a controller having a load overload device.
To comply with the National Electrical Code, NFPA 70, electric motors larger than one horsepower are required to use overload devices. The overload devices are intended to protect electric motors and branch circuits from undue heating caused by excessive current.
Induction electric motors are widely used. Induction motors are generally specified by a variety of rated capacity parameters such as torque, horsepower, current, voltage, frequency, temperature, starting time, and the like. While induction motors have a simple robust physical design, induction motors rely on complex nonlinear relationships to function. For example, when an inductive motor is first turned on to drive a machine, the inductive motor can draw an additional amount of current to provide additional torque to drive the machine. The additional amount of current drawn is generally referred to as an inrush current that can last for a few seconds. The inrush current can sometimes be ten times higher than that of a normal running current. The additional torque can sometimes be three times that of a normal operating torque. After the driven machine reaches a normal operating state or speed, the current drawn will drop below the name plate current value or rated current capacity.
However, when the machine being driven becomes jammed or impaired in some manner, the motor will draw additional current or power to churn out additional torque in an attempt to move the machine. When the amount of the operating current drawn by the motor exceeds a certain rated amount, an overload device associated with the machine will trip. For example, an overload of about 125 percent of the rated current of the motor for about 600 seconds, or about 600 percent of the rated current of the motor for about ten seconds will trip the overload device. However, the additional torque can last for a period of time before the overload device trips. While the machine being driven is jammed or impaired and before the overload device trips, the jammed machine can destroy any jammed material or itself.

Apparatus having a motor, controller for the motor, and method of controlling the motor


A system for mounting taxidermy animal trophies on mounting devices comprises a support platform having a rod protruding therefrom. The rod is a ribbed member having a large plurality of features for securing an animal mount, such as a skull, thereto. For example, the ribbed member may comprise a concrete reinforcement bar that may be sized in diameter and length according to the size of the mount. The rod uses the natural occurring or existing hole or holes in the back of the skull for support thereof. The rod may extend straight from the support platform, such as for wall mounting purposes, or may comprise a bent portion at a distal end thereof for surface display of the mount.

1. Technical Field
The present invention relates in general to taxidermy and, in particular, to an improved system, method, and apparatus for mounting taxidermy animal trophies on mounting devices.
2. Description of the Related Art
There are numerous types of hangers and supports available to taxidermists. These hangers are attached to a mounted specimen and then hung on a wall or plaque for display purposes. One type of prior art device uses a panel or support panel with a smooth rod extending therefrom. The rod is typically bolted to the support panel. The skull of an animal is then placed on the smooth rod. The space between the rod and the skull is then filled with a fill material, such as fiberglass or Bondo. The fill material ensures that the skull stays correctly positioned on the rod, but also permanently attaches the skull to the rod. Although this design is workable, an improved mounting device for mounting taxidermy animal trophies would be desirable.

System and apparatus for mounting a taxidermy trophy


A computer-implemented method can receive a request from a robotic process automation engine to identify a target user interface control element in a webpage represented by a current master data frame. The current master data frame comprises a current document object model (DOM). The method can determine that a target user interface control element identifier associated with the target user interface control element is absent in the current DOM. The method can retrieve an archived version of the target user interface control element from an archived master data frame of the webpage. The method can find an equivalent user interface control element within the current master data frame based at least on the archived version of the target user interface control element, and output an equivalent user interface control element identifier associated with the equivalent user interface control element.

Robotic process automation (RPA) can use automation scripts, known as software robots, to automate and standardize repeatable business processes. RPA can mimic human activities by interacting with applications in the same way that a person does, thus having the potential to improve work productivity and reducing human error.
However, current RPA systems do not perform well with a web-based user interface (UI) because properties associated with a user interface control element in a webpage may change over time such that the user interface control element cannot be identified by the RPA systems.
Thus, there remains a need for an adaptive web-based RPA system that can automatically identify the missing control elements in a webpage regardless of the underlying user interface framework.

Adaptive web-based robotic process automation


During synchronization of data between a remote device and a local device, it can be determined if a value for a property on a remote device has changed since a last synchronization of the property between the remote device and a local machine. A remote representation of a property value is compared to a local representation associated with the same property value. If the representations are identical, it can be determined that the property value did not change on the remote device. If, however, they are not identical then the property value must have changed after the remote representation was generated.

1. The Field of the Invention
The present invention generally relates to synchronizing data within a distributed computing system. More particularly, example embodiments provide for determining if a property value on a remote low fidelity device has changed since a last synchronization with a local machine.
2. Background and Related Art
Laptop, handheld, and other portable computers or computing devices have increased in popularity as the devices become smaller in size and less expensive. Additionally, improved operating speed and processing power of portable computers has increased their popularity. Many portable computers are capable of storing multiple application programs, such as address books, games, calculators, and the like. The application programs can be permanently installed in the portable computer during manufacture (e.g., on Read-Only Memory (ROM)). Alternatively, one or more application programs may be installed by the user after purchasing the portable computer.
With the increased popularity and computing power of such devices, people are beginning to store data and applications using more than just a single computing device. Many people, for example, often use laptop computers in addition to their regular desktop computer. Other devices such as cellular telephones, Personal Digital Assistance (PDAs), Internet services, and the like are also used for storing data and applications.
Each of these computing devices may be part of a distributed computing system wherein related information can be correlated and stored on multiple such devices. For example, a user may have a digital address book stored on their desktop work computer, on their PDA, on their cell phone, on an Internet service, etc. Accordingly, while at work, it may be convenient for the user to access contact information, which may include phone numbers and other general contact information. While away from work, however, the user may be able to use the address book in a mobile form such as a personal digital assistance (PDA) or other mobile information storage system. Ideally, the contact information of the PDA should match the contact information at the desktop work computer.
When the same or related information is stored in two places, it is possible for the data to change in one location and not in the other. This problem may be overcome through synchronization, which is an automated process that attempts to ensure that each device within the distributed system has the most current information or data. Synchronization, however, has its own set of problems. For example, when synchronization is initialized between the two devices, current systems detect changed property values by comparing corresponding property values from each device. Such comparison, however, gives no indication as to which device made the change. As such, when a property change has occurred on either device, a conflict occurs and a conflict resolution process must be performed.
Other systems mark a changed property with a tag indicating that a change has occurred, e.g., "change," "delete," "add," or other tag, as appropriate. In such systems, however, when two devices start syncing, a local device can create these markers in memory after comparing the data for what needs to be applied. Further, because the tags are only tracked in memory, these tags are not stored in a remote database for use during synchronization with other devices. In other words, conflicts must first be reconciled and then the properties can be marked and tracked in local memory only.
Typically, conflicts can be resolved through comparing metadata associated with the property values that give, e.g., time-date information. The latest time-date information is considered the most up-to-date information and the properties can be updated accordingly. Resolving a conflict by comparing time-date information becomes particularly problematic when the data to be synchronized does not include time-date information, which is referred to as low fidelity data. For example, many smaller computing devices have limited physical resources and are incapable of maintaining time-date information for properties of a data structure item. As such, when a computer syncs data in from such low fidelity device, it doesn't know when the user originally set that property. This prevents the computer from syncing in a property from another computing device and confidently using "last-writer-wins" resolution logic to pick the most up-to-date property. Further, even if no conflict existed, there is typically no way to sync the property change to the receiving device without a conflict resolution process.

Determining when a low fidelity property value has changed during a sync


An adjustable laser module has a main body, a laser generator provided in the hollow interior of the main body at a first end thereof for emitting a laser beam, a cylindrical lens provided in the hollow interior at a second end thereof, a first adjusting device coupled to the first end and the laser generator for adjusting the angle of the laser generator with respect to the main body, and a second adjusting device coupled to the second end and the cylindrical lens for adjusting the angle of the cylindrical lens with respect to the main body.

1. Field of the Invention
The present invention relates to a laser module device, and in particular, to a laser module device which can adjust the inclination angles of a laser generator that emits a laser beam, and of a cylindrical lens that receives the laser beam.
2. Description of the Prior Art
The laser is a remarkable invention in modern science. The theory of generating laser light is as follows. According to Bohr's atomic theory, the electrons distributed around atoms or molecules all have a certain energy. The energy of an electron is the sum of its kinetic energy and potential energy, and can only be located at a specific energy level among a series of discontinuous separate energy levels. The state with the lowest energy is called the ground state (low-energy state). Although most electrons are usually in the ground state with the lowest energy in a state of thermal equilibrium, when energy in any form (heat, light, electricity, chemical effect, etc.) is added from outside to the electrons in the ground state, the electrons will be excited and move to a higher-energy state (excited state). The excited state is not stable and has a tendency to return to the low-energy state. At that time, the electrons at the higher energy level will fall back to the ground state due to stimulated emission, and release the excess energy at the same time. The excess energy will be converted to hv (h: Planck constant, v: light frequency), that is, the so-called light quantum or photon. If the electrons stay in the excited state longer than the time that they stay in the ground state, or if many particles at the low energy level can be moved to a higher-energy level in a very short period of time, and if the electrons in the excited state generate stimulated emission (high energy level/low energy level) that is accompanied with the release of photons at the same time, it is possible to generate a large quantity of light with the same orientation, the same frequency, and the same phase if the light is amplified repeatedly by a back-coupling mechanism. This is the basic theory of generating a laser beam.
A laser module includes a laser unit used for generating a laser beam, and a corresponding control circuit. With the aid of a lens, this device can generate a highly-collimated laser beam. The laser module has therefore been used widely in various application fields. For example, the popular laser pointer is formed by adding a laser module at the front end of a pen body. The laser beam generated by the laser module can form a very bright light spot on an object for instructional purposes. In addition, a laser module can also be used for a collimator, level meter, laser projector, etc.
FIGS. 1A and 1B illustrate the structure of a conventional laser module. A conventional laser module 1 has a hollow cylindrical structure as a housing space 11. A laser generator 12 and a cylindrical lens 13 are respectively connected to the opposite ends of the housing space 11. A convex lens 15 is positioned in the middle of the housing space 11 between the laser generator 12 and the lens 13. After the device is turned on, laser generator 12 will emit a laser beam. The laser beam becomes parallel after passing through the housing space 11 and the convex lens 15. The light beam then reaches cylindrical lens 13 where it is refracted. A light shield 14 can be used to eliminate parasitic light to provide a linear laser beam for use. However, deviation usually occurs in the mounting angle of the laser generator 12 when it is connected inside the housing space 11. As a result, the laser beam does not travel along the central axis 16 of the housing spacing 11, resulting in deviation in the angle of incidence on the cylindrical lens 13. Alternatively, if there is deviation in the mounting angle of the cylindrical lens 13 when it is mounted inside housing space 11, the laser beam will lose most of its energy after it is refracted by the cylindrical lens 13. As a result, a relatively short or weak linear laser beam, or a laser beam with relatively large curvature, will be generated. Such laser beams will not meet the user's requirements.
Consequently, there is a need for improved laser modules which overcome the drawbacks described above.


A method for producing a pelletized pavement marking mixture includes selecting an appropriate thermoplastic binder that is a solid at ambient temperatures and heating the appropriate thermoplastic binder in a reaction vessel to a temperature sufficient to form a liquid thermoplastic binder; forming a heated pavement marking mixture by adding a plasticizer and a filler to the liquid thermoplastic binder in the reaction vessel; forming a substantially homogeneous pavement marking mixture by blending the heated pavement marking mixture for period sufficient to substantially evenly distribute the plasticizer and the filler within the liquid thermoplastic resin while maintaining the heated pavement mixture at an elevated temperature; extruding the substantially homogeneous pavement marking mixture from the reaction vessel to form an extruded substantially homogeneous pavement marking mixture; and pelletizing the extruded substantially homogeneous pavement marking mixture. A pavement marking mixture consists of a substantially homogeneous mixture of pellets. Each of the pellets in the pavement marking mixture consists of a substantially homogeneous blend of a thermoplastic binder, a plasticizer, and a filler. The method for making a pelletized pavement marking mixture can be extended by adding a pigment and retroreflective particles to the heated pavement marking mixture.

Pavement markings are used extensively to visually delineate portions of a road surface, for example, the edges or center of the road surface. In some applications, the pavement marking is simply a colored mixture. For example, Regenstein et al., U.S. Pat. No. 3,297,617 disclose a coating slurry that can contain various pigments which can be used to mark a road surface. Frequently, retroreflective particles, such as glass beads, are added to pavement markings to improve the visibility of the pavement marking in adverse situations, such as at night. Bollag, U.S. Pat. No. 4,856,931 discloses a pavement marking that is produced by painting a line on the pavement and thereafter scattering glass beads over the painted line while the paint is still tacky. Shuger, U.S. Pat. No. 2,268,537, de Vries, U.S. Pat. No. RE 28,531, La Roche, U.S. Pat. No. 5,128,203, and Rodli et al., U.S. Pat. No. 2,330,843 similarly disclose solvent-based pavement marking mixtures that are applied to the pavement, for example, by spraying. Glass beads are then applied to the mixtures while the mixtures are still semi-wet or tacky. Kullenberg, U.S. Pat. No. 2,879,171 discloses a solvent-based pavement marking mixture that includes glass beads in a stabilized aqueous dispersion.
Pavement marking mixtures using non-solvent based materials have been proposed. La Roche, U.S. Pat. No. 5,128,203 discloses a two component acrylic matrix-forming material that is applied to the pavement. Glass beads are then sprinkled over the applied matrix-forming material within one minute of mixing the acrylic matrix-forming material. La Roche also discloses a pavement marking kit based on a thermoplastic matrix-forming material. The thermoplastic matrix-forming material is heated and applied to the pavement. Glass beads are then sprinkled over the thermoplastic material while it is still liquid. Haenggi et al., U.S. Pat. Nos. 4,937,127, 5,053,253, and 5,124,178 disclose a pavement marking tape that includes a base sheet which has an upper polymer matrix surface. Glass beads are embedded in the matrix surface before it is cured. The final tape product, which includes glass beads, is then affixed to a road surface with an adhesive. Jorgensen et al., U.S. Pat. No. 3,849,351 disclose a particulate pavement marking mixture that includes a thermoplastic phase which consists principally of polyamide condensation products of polycarboxylic acid and polyamine, and glass beads. The pavement marking mixture is applied to a road surface using a flame-applicator.
Conventional pavement marking mixtures suffer from disadvantages. As noted earlier retroreflective particles, such as glass beads, are frequently added to the surface of pavement markings before the pavement marking mixtures have set-up on the road surface. Initially, the surface-added retroreflective particles improve the visibility of the pavement markings. However, the retroreflective particles tend to wear away under traffic and the like. Thus pavement marking mixtures that depend on surface-added retroreflective particles to enhance their visibility lose their retroreflective characteristics over time, also relatively long application times are required for solvent-based pavement marking mixtures. Solvent-based pavement marking mixtures generally become set when the solvent evaporates. The amount of time required for the solvent to evaporate varies with the type of solvent used and the solvent-percentage composition. However, drying times on the order of 15 to 60 minutes are not unusual. Consequently, pavement markings formed from solvent-based pavement marking mixtures frequently must be protected from traffic for relatively long periods. The setting time for solvent-based mixtures thus restricts traffic flow and increases the cost of using such mixtures.
Conventional thermoplastic-based pavement marking mixtures suffer from additional disadvantages. Conventional thermoplastic-based pavement marking mixtures generally are marketed as heterogeneous mixtures of individual, raw components. Consequently, the end-user must mix together the raw components at elevated temperatures for significant time periods before the pavement marking mixture is ready to be applied to a road surface. In addition, the raw components generally have varying melting temperatures and so are not readily liquified. Extended mixing times and variable temperature requirements increase the cost of applying the mixture to a road surface and thus increase the cost of using such mixtures.

Method for producing pelletized pavement marking mixtures


Disclosed are a plasma display apparatus and a driving method thereof. The plasma display apparatus comprise a plasma display panel having a scan electrode and a sustain electrode, a scan driver for sequentially supplying a first rising ramp waveform, a first falling ramp waveform and a second falling ramp waveform to the scan electrode during the reset period of the first subfield of a plurality of subfields, and a sustain driver for supplying a round waveform to the sustain electrode while the first rising ramp waveform is being supplied to the scan electrode. In the driving method of a plasma display apparatus, which divides a plurality of subfields with a different number of times of light emission into a rest period, an address period and a sustain period, and displays an image by applying a signal to the scan electrode, sustain electrode and address electrode in the respective periods, a surface discharge occurs two times between the scan electrode and the sustain electrode in the reset period of the first subfield of the plurality of subfields, and an opposite discharge occurs between the scan electrode and the address electrode.

1. Field of the Invention
The present invention relates to a plasma display apparatus and a driving method thereof, and more particularly, a plasma display apparatus that is capable of improving contrast and driving margin by enhancing a driving waveform supplied in a reset period of each subfield, and a driving method thereof.
2. Description of the Background Art
Generally, a plasma display panel (PDP) radiates a phosphorus by an ultraviolet with a wavelength of 147 nm generated during a discharge of He+Xe or Ne+Xe gas to thereby display a picture including characters and graphics.
FIG. 1 is a perspective view showing a structure of a conventional three-electrode AC surface plasma display panel. As shown therein, the three-electrode AC surface-discharge PDP includes a scan electrode 11(hereinafter, 'Y electrode') and a sustaining electrode 12(hereinafter, 'Z electrode') formed on an upper substrate 10, and an address electrode 22(hereinafter, 'X electrode) formed on a lower substrate 20. The Y electrode 11 and the Z electrode 12 are formed from transparent electrodes, e.g., indium-tin-oxide (ITO), 11a and 12a, respectively. Bus electrodes 11b and 12b are formed on the Y electrode 11 and the Z electrode 12, respectively, so as to reduce resistance. On the upper substrate 10 provided with the Y electrode 11 and the Z electrode 12, an upper dielectric layer 13a and a protective film 14 are disposed. Wall charges generated upon plasma discharge are accumulated in the upper dielectric layer 13a. The protective film 14 protects the upper dielectric layer 13a from a sputtering generated during the plasma discharge and improves the emission efficiency of secondary electrons. This protective film 14 is usually made from MgO.
A lower dielectric layer 13b and barrier ribs 21 are formed on the lower substrate 20 provided with the X electrode 22. A phosphorus layer 23 is coated on the surfaces of the lower dielectric layer 13b and the barrier ribs 21. The X address electrode 22 is formed in a direction crossing the X electrode 11 and the Z electrode 12. The barrier ribs 21 are formed in parallel to the X electrode 22 to prevent an ultraviolet ray and a visible light generated by the discharge from being leaked into the adjacent discharge cells. The phosphorus layer 23 is excited and radiated by an ultraviolet ray generated upon plasma discharge to produce a red, green or blue color visible light ray. An inactive mixture gas, such as He+Xe or Ne+Xe, for a gas discharge is injected into a discharge space defined between the upper/lower substrate 10 and 20 and the barrier ribs 21. A driving waveform according to a driving method of a conventional plasma display panel having such a structure will be described as shown in FIG. 2.
FIG. 2 is a view showing a driving waveform according to a driving method of a conventional plasma display panel. As shown in FIG. 2, the plasma display panel is divided into a reset period for initializing, the full fields, an address period for selecting a cell to be discharged, a sustain period for sustaining a discharge of the selected cell for its driving, and an erase period for erasing wall charges within the discharged cell.
In the reset period, a rising ramp waveform Ramp-up is simultaneously applied to all the scan electrodes Y in a set-up interval. This rising ramp waveform Ramp-up causes a discharge within cells at the full field to generate wall charges within the cells. The setup discharge causes positive wall charges to be accumulated in the address electrode X and the sustain electrode Z, and negative wall charges to be accumulated in the scan electrode Y. In the set-down internal, after the rising ramp waveform was supplied, a falling ramp waveform Ramp-down, falling from a positive voltage lower than a peak voltage of the rising ramp waveform to a specific voltage level lower than the ground(GND) level voltage, causes a weak erasure discharge within the cells, to thereby erase excessive wall charges. The set-up discharge causes wall uniformly left within the cells of the full field to the extent that an address discharge may be performed stably.
In the address period, negative scan pulses SCAN are sequentially applied to the scan electrodes Y and at the same time positive data pulses DATA synchronized with the scan pulses SCAN are applied to the address electrodes X. When the voltage difference between the scan pulse SCAN and the data pulse DATA is added to the wall voltages generated in the reset period, the address discharge is generated within the cell to which the data pulse DATA is applied. When sustain voltages Vs are applied, wall charges to the extent that the discharge might be generated are formed within the cells selected by the address discharge. Positive DC voltage Vz is applied to the sustain electrode Z for the set-down interval and the address period so as not to generate a mis-discharge between the scan electrode Y and the sustain electrode Z.
In the sustain period, sustain pulses SUS are alternately applied to the scan electrodes Y and the sustain electrodes Z. In the cells selected by the address discharge, a sustain discharge, i.e., display discharge, is generated between the scan electrode Y and the sustain electrode Z whenever each sustain pulse SUS is applied as the wall voltage within the cell is added to the sustain pulse SUS.
Finally, after the sustain discharge has been finished, a voltage of an erasing ramp waveform Ramp-ers having a small pulse width is applied to the sustain electrode Z to thereby erase wall charges left within the cells of the full screen.
In the conventional driving method of a plasma display panel to which a driving waveform is adapted, the black brightness is relatively high upon driving, thus leading to a problem of deteriorating the contrast ratio of the panel.
Recently, the content or Xe tends to be increased in order to enhance discharge efficiency in the sealed discharge gas of the PDP. In this case, if a driving waveform according to the conventional driving method of the plasma display panel is adapted, the interference of the address electrode Y on a discharge between the scan electrode and the sustain electrode Z is increased to thus increase a reset voltage. Resultantly, in the event such a driving waveform is adapted to a large screen, there is a problem that the driving margin of the panel is deteriorated.
Moreover, there is a problem that if the content of Xe is increased, the address jitter characteristic is deteriorated, which makes a sustain discharge unstable in the subsequent period, i.e., a sustain period.

Plasma display apparatus and driving method thereof


A multi-disk brake system comprises an electrical generator disposed therein. The electrical generator is configured to convert mechanical energy to electrical energy. The mechanical energy may be generated during a braking event of the multi-disk brake system. The electric generator may power various electrical components on the aircraft or store the electrical energy in a capacitor bank. The electric generator may also act as a motor and/or power a landing gear in a motor configuration.

Aircraft multi-disk brake systems typically employ a series of friction disks forced into contact with each other to stop the aircraft. Friction disks splined to a non-rotating wheel axle are interspersed with friction disks splined to the rotating wheel. The friction disks withstand and dissipate the heat generated from contact between one another during braking. The friction disks may experience wear during braking events. Kinetic energy generated during braking events is typically lost to heat.


A method for detecting and recovering from a transmission channel change during a streaming media session is disclosed. The method can include a wireless communication device detecting a stall condition resulting from a transmission channel change. The method can further include the wireless communication device capturing a snapshot of a current transmission parameter state of the streaming media session in response to detecting the stall condition. The method can also include the wireless communication device using the snapshot to restore the streaming media session to the transmission parameter state captured by the snapshot following completion of the transmission channel change.

Media streaming applications that stream media from a wireless communication device over a wireless network can suffer from stall conditions in which media packets become stalled in a baseband queue and cannot be transmitted from the wireless communication device. As a result of a stall condition, rate control mechanisms can quickly ramp down a rate at which media packets are generated and/or transmitted. After recovery from the stall condition, a slow ramp up period can occur in which media packet transmission rate can slowly recover to the pre-stall condition. The stall and slow ramp up period can accordingly negatively impact user experience.
In some instances, a stall condition can result from degradation of a network channel condition, such as a wireless channel by which the wireless communication device can be connected to a cellular base station or other wireless network access point. In such instances, it can be appropriate to enter a slow ramp up period following recovery from the stall condition. In this regard, slow ramp up can be used to avoid flooding a potentially bad network connection with a larger volume of packets than the network connection is capable of handling.
However, in some instances, a stall condition can be caused by an event other than degradation of a network channel condition. For example, in some instances, a stall condition can be caused by a device changing transmission channels. In this regard, some wireless communication devices have multiple transmission channels and can switch transmission channels during an active streaming media session in order to use a channel with better conditions. In instances in which a transmission channel change is performed, a network channel condition may not have degraded. As such, using standard rate control mechanisms that implement a slow ramp up period following a stall condition resulting from a transmission channel change can unnecessarily degrade user experience for an extended period following the stall condition.

Detecting and recovering from a transmission channel change during a streaming media session


A cable connector assembly (100) includes a housing (1) including a base portion (13) and a tongue portion (14) extending from the base portion, a printed circuit board (2) received in the housing, a cable (7) electrically connecting with the printed circuit board, and a latch member (31) assembled to the metal housing. The cable connector assembly further includes an EMI gasket (5) assemble to the tongue portion for reducing EMI during signal transmission and including a periphery wall (50) circumscribing a space (51) for the tongue portion protruding through, a number of tubers (52) extending from the periphery wall and locating on the same plane as the periphery wall and a number of spring fingers (502, 504) extending from a front surface of the periphery wall.

1. Field of the Invention
The present invention generally relates to a cable connector assembly, and more particularly to a cable connector assembly used for high-speed signal transmission.
2. Description of Related Art
A committee called SFF is an ad hoc group formed to address storage industry needs in a prompt manner. When formed in 1990, the original goals were limited to define de facto mechanical envelopes within disk drives can be developed to fit compact computer and other small products. Specification SFF-8088 defines matable Compact Multilane Shielded connectors adopted for being used in laptop portable computer to connect small-size disk drives to a printed circuit board. The connectors comprise a cable connector assembly connecting with the small-size drive and a header mounted on the printed circuit board. The cable connector assembly defined in the specification comprises a metal housing defining a receiving space, a PCB received in the receiving space, a cable comprising a plurality of conductors electrically connecting with the PCB, and a latching mechanism assembled to the metal housing. The metal housing comprises a base portion to which the latching mechanism is assembled and a tongue portion extending forwardly from a front surface of the base portion. The cable connector assembly further comprises an EMI (Electro Magnetic Interference) gasket assembled to the tongue portion and attaching to the front surface of the base portion for touching with a panel on which the header connector is mounted to reduce EMI. The EMI gasket is retained to the tongue portion by friction therebetween. However, such fashion may cause unstable connection between the EMI gasket and the cable connector assembly. The EMI gasket may separate from the cable connector assembly and thus, the function of reducing EMI through contacting with the panel cannot be assured and the signal transmission between the cable connector assembly and the header connector is influenced.
To enhance the function of reducing EMI, grounding elements with different structures and similar function as the EMI gasket have been developed and disclosed in U.S. Pat. Nos. 3,922,056, 4,386,814, 5,622,523, 5,967,842, 6,074,218, 6,227,904 and 6,095,862 et al. However, these types of grounding elements are not suitable to the cable connector assembly disclosed above. A new type of EMI gasket is needed to be provided to meet the requirements of the cable connector assembly.

Cable connector assembly with EMI gasket


Methods of fabricating a multi-region U-shaped composite structure, the methods comprising the steps of laying up a first composite material on a first tool piece to form a first sidewall, laying up the second composite material on a second tool piece tool to form a second sidewall, re-orienting the first tool piece and the second tool piece to a consolidation orientation, laying up the third composite material to form a nose wall, and overlapping at least a portion of the third composite material with at least a portion of the first composite material and at least a portion of the second composite material.

Composite U-shaped structures with high depth-to-opening aspect ratios preclude several layup options such as laser projection due to limited fabrication accessibility. Bridging in nose areas is also common due to the long fiber draw distances during debulking and due to the practice of clamping sidewalls of the structures. Furthermore, such composite U-shaped structures employ homogenous architecture, which necessitates compromises in the nose areas or the sidewalls.

Methods of fabricating multi-region U-shaped composite structures


An endocoupler system having an endocoupler (110) and a myeloscope (210). The present invention relates to an endocoupler system. More particularly, the present invention relates to an endocoupler system consisting of an endocoupler connected to a myeloscope. The present invention is a system to directly view the pathology of the epidural space in the lower spine region using a miniature endoscopic catheter device. This device is currently used by physicians to diagnose and treat patients who suffer from chronic low back pain. The present invention consists of a developed medical procedure, disposable procedure access kit, multi-lumen steerable catheter (Video Guided Catheter), small fiber optic endoscope (Myeloscope), endocoupler (Endocoupler), light source, and camera system. A major feature of the invention is the ability to orientate the viewing plane with respect to the image transmitted through the image fiber bundle by rotation of the image fiber coupler in a plane that is normal to the central optical axis of the objective lens assembly and image fiber coupler. This is accomplished in the present invention which is designed permitting the endocoupler to rotate allowing the image fiber coupling to be oriented at the connection point to the endocoupler. This is accomplished by means of a collet assembly which allows the user to loosen the collet and rotate the image fiber coupler to the desired orientation as viewed on the monitor and re-tighten the collet.

1. Field of the Invention
The present invention relates to an endocoupler system. More particularly, the present invention relates to an endocoupler system consisting of an endocoupler connected to a myeloscope.
2. Description of the Prior Art
The endocoupler system was developed to satisfy a need that every pain practitioner has faced for the last 60 years. The need to directly visualize the pathology in-situ in and around the nerve roots as they make their way out of neural forming along the axis of the spinal cord. Other means of visualizations such as Fluoroscopy, MRI and CAT Scans cannot produce real time images of the pathology or disease and cannot clearly differentiate soft tissue pathology. Epidural endoscopy was practically impossible if performed utilizing ridged optics and the paramedian or lumbar approach. This is due to the fact that the spinal cord is encased by an articulating bone structure with minimal access possibilities. Any device with the capability to access the epidural space would have to be flexible and very small. Using miniature fiberoptic endoscopes and miniature multi lumen steerable catheters the inventor has developed a medical device that introduces epidural space. The present invention allows physicians to directly visualize the epidural space of the spine and treat patients for related diseased in a minimally invasive manner.
Numerous innovations for an endoscope system have been provided in the prior art that are described as follows. Even though these innovations may be suitable for the specific individual purposes to which they address, they differ from the present invention as hereinafter contrasted.
In U.S. Pat. No. 5,435,805, titled Medical Probe Device with Optical Viewing Capability, invented by Stuart D. Edwards, Hugh R. Sharkey, Ingemar H. Lundquist, Ronald G. Lax and James A. Baker, Jr., a medical probe device comprising a catheter having a styler guide housing with at least one stylet port in a side thereof and stylet guide means for directing a flexible stylet outward through at least one stylet port and through intervening tissue to targeted tissues. The stylet guide housing has an optical viewing means positioned for viewing the stylet and adjacent structure which includes a fiber optic channel means for receiving a fiber optic viewing device. The fiber optic channel means can include a guide port means for directing longitudinal movement of a fiber optic device with respect to the stylet guide means in a viewing zone and a flushing liquid channel in the stylet guide housing having an exit port positioned to direct flushing liquid issuing therefrom across the end of a fiber optic device when positioned in the viewing zone. The optical viewing means can comprise a viewing window positioned in the stylet guide housing for viewing the stylet when it is directed outward from its respective stylet port. The optical viewing means can includes a fiber optic channel in the stylet guide housing for receiving the fiber optic, viewing device and aligning the viewing end thereof with the viewing window. Windowed devices can include a flushing liquid channel in the stylet guide housing having an exit port positioned to direct flushing liquid issuing therefrom across a surface of the viewing window.
In U.S. Pat. No. 5,429,604, titled Fiber Optic Catheter with Twistable Tip, invented by Dan J. Hammersmark, Timothy J. Wood, and Matthew S. Solar, the present invention is a catheter with a twistable tip. The catheter having a flexible wall for use in complex twisting anatomy contains a torque wire or a torquable guide wire lumen. The torque wire or torquable guide wire lumen extends through the length of the catheter and is attached to the catheter at or near the distal end thereof. The distal face of the catheter is angled to self align the catheter with an obstruction upon insertion. The proximal end of the torque wire protrudes from the proximal end of the catheter and is attached to a turn limiter. Rotation of the turn limiter imparts a torque to the torque wire or torquable guide wire lumen which is transmitted through the catheter to the distal end of the catheter where the applied torque twists the distal tip to manually align the tip with an obstruction. The twisting response at the tip of the catheter is determined by the torque applied to the torque element, the material and dimensional profile of the torque element, the attachment point of the torque element to the catheter and the material and dimensional profile of the catheter.
In U.S. Pat. No. 5,423,311, titled Catheter Imaging Apparatus, invented by Phillip J. Snoke, Stephen C. Gamper, David S. Rowley and Bruce W. Copeland, a catheter imaging apparatus for internally viewing body vessels or cavities, having a catheter, the catheter comprising a housing of such a size as to be readily held in the hand of a user, an elongate tube with one end connected to the housing and extending outwardly therefrom and being formed of material having sufficient stiffness to maintain the elongate tube in a substantially straight condition in the absence of an external force applied thereto, the elongate tube having a flexible distal end portion, guide wires having inner ends connected to the housing and extending outwardly therefrom through the elongate tube means, distal ends of the guide wires being connected to the flexible distal end portion of the elongate tube means, and a guide wire control carried by the housing and cooperating with proximal inner end portions of the guide wires for controlling the angular attitude of the flexible distal end portion of the elongate tube means, the guide wires and guide wire control cooperating to limit the angular attitude of the flexible distal end portion of the elongate tube to angular adjustments in a common plane extending generally parallel to the upper surface of the housing, and an imaging source for forming an image of an internal body cavity or vessel into which the catheter is inserted, the imaging means being in optical communication with the flexible distal end portion of the elongate tube of the catheter.
In U.S. Pat. No. 5,349,942, titled Flexible Endoscope, invented by Rudolf Helmberger, an endoscope with a flexible shaft, which consists of individual subassemblies releasably connected to each other. The proximal end of a flexible shaft is joined to a connecting portion and the distal end of the shaft can be steered into different positions by adjustment of an operating wire by means of an adjusting lever. The connecting portion can be coupled releasably to the distal end of the handle portion, at the proximal end of which an eyepiece portion is arranged. A hand-operated control means for the operating wire is provided in the handle portion, wherein the proximal end of the operating wire is clamped by a receiver in the control means. The receiver can be opened by operation of the adjusting lever for the purpose of releasing the above mentioned wire end, by moving the adjusting lever forwards of a neutral position. Moving the adjusting lever backwards from the neutral position effects longitudinal movement of the operating wire for controlling movement of the flexible shaft.
The above patented inventions differ from the present invention because the patented inventions each lack one or more of the following features which are described and claimed in the present invention: an endocoupler (110) which comprises: an endocoupler camera/eyepiece mount which is either an endocoupler camera mounting means or an endocoupler eyepiece viewing means consisting of an endocoupler eyepiece, an endocoupler eyepiece lens, and an endocoupler eyepiece lens holder, an endocoupler focus ring, an endocoupler body consisting of an endocoupler body objective lens assembly, an endocoupler body window holder, and an endocoupler body collet body, and an endocoupler collet knurled ring. A myeloscope is rotatably mounted to the endocoupler. The myeloscope consists of features such as: a myeloscope image coupler body having a myeloscope image coupler body male connector, a myeloscope fiberoptic endoscope consisting of a myeloscope fiberoptic endoscope distal end and a myeloscope fiberoptic endoscope light/image fiber bundle consisting of a myeloscope fiberoptic endoscope image fiber bundle and a myeloscope fiberoptic endoscope light fiber bundle, a myeloscope strain relief tubing, a myeloscope ACMI light port body having a myeloscope ACMI light port body attachment means, and a myeloscope fiber optic light guide scope lead having a myeloscope fiber optic light guide scope lead strain relief tubing.
Numerous innovations for an endoscope system have been provided in the prior art that are adapted to be used. Even though these innovations may be suitable for the specific individual purposes to which they address, they would not be suitable for the purposes of the present invention as heretofore described.


A calling account recharge system, method, and device are provided. The device has an associated stored-value calling account, and typically includes a selector, a communications program configured to communicate with a recharge service via a communication network, and a recharge option selectable by a user upon actuation of the selector. The recharge option is configured to cause the communications program to initiate a recharge transaction with the recharge service via the communication network, in order to add calling units to the stored-value calling account. The device may be configured to access the communication network via a toll-free gateway.

Stored-value calling accounts are used by a large number of telephone users to place calls around the world. In a typical scenario, a user purchases a wireless telephone linked to a stored-value calling account with a balance of, for example, $100 of calling units. The user may be given a plastic card containing an account number and pin, as well as a telephone number that the user may call to service the account. Such plans are typically commercially marketed under the label "PrePaid Wireless," and can be distinguished from conventional "post-paid" telephone plans.
As the user makes calls using the wireless telephone, calling units are deducted from the account. The deduction may be made either by software in the telephone itself, or by specialized telephone switching equipment configured to carry such pre-paid telephone calls. At the beginning of each outbound call, the user is typically prompted with a number of available minutes, or calling units. A warning tone may be emitted during a call if the account balance falls below a predetermined minimum threshold. If the account balance reaches zero, the current call will be disconnected and the user will be prevented from making further calls.
The user may add calling units to the account in a process referred to as "recharge." According to current recharge systems, recharge may occur in one of two ways. First, the user may visit a retail outlet of the wireless service provider or an authorized dealer and request that minutes be added to the stored-value account. Second the user may call the access number printed on the card discussed above, and request that a customer service representative add time to the account. However, the user must typically authorize dial-up recharge when opening the stored-value account. Where this option is not pre-authorized by the user, the user typically purchases a new stored-value card at a retail outlet, as discussed above.
Unfortunately, these current recharge methods are inconvenient for wireless telephone users. Traveling to a retail location or authorized dealer is time consuming and expensive. Calling a customer service representative is inconvenient because the user may be out of minutes on the wireless telephone. If so, the user will be forced to call the customer service representative from a different telephone. In addition, it is also difficult for the user to remember the access number of the customer service representative, and the telephone card containing the access number may become lost or difficult to locate. Based on the foregoing, alternative approaches for recharging a stored-value calling account are desirable.

Toll free calling account recharge system and method


An integrated circuit (IC) has scan chains of stitched registers that support scan testing of functional logic. The scan testing has a shift phase in which incoming and outgoing data are shifted into and out of the registers using a slow clock and a capture phase in which outgoing data from the functional logic is captured by the registers using launch-and-capture pulses of a fast clock to check for delay faults. During a warm-up period after termination of the slow clock but before application of the launch-and-capture pulses, the registers propagate data through their master latches without affecting the data stored in their slave latches. A warm-up controller configures the registers and generates control signals to perform either launch-on-shift or launch-on-capture scan testing. The flow of data and the warm-up controller operations keep the power supply rail voltage sufficiently charged for the fast launch-and-capture pulses.

The present invention relates generally to electronics and, more particularly, to scan testing of integrated circuitry.
Some integrated circuits (ICs), such as system-on-chip (SoC) devices, have multiple registers (e.g., flip-flops) that are stitched into scan chains to enable scan testing of the IC to detect structural faults in the functional logic of the IC and where at-speed patterns are used to check for delay faults in the functional logic. These scan chains are stitched between a decompressor, which functions as a stimulus generator for the logic under test, and a compactor, which functions as a signature generator for the corresponding response captured from the logic under test. Such scan testing is well known and typically performed through shift and capture phases of multiple scan-test cycles with different stimuli orchestrated by off-chip tester equipment (i.e., an automatic test-pattern generation (ATPG) tool), where each shift Phase is driven using a relatively slow tester clock provided by the ATPG tool and each capture phase is driven using a relatively fast at-speed clock generated by on-chip clock (OCC) circuitry.
FIG. 1 is a block diagram of conventional, on-chip scan-testing circuitry 100 for an SoC or other IC having computational logic (not shown in FIG. 1). The scan-testing circuitry 100 includes (i) a decompressor 110 (e.g., a linear feedback shift register (LFSR) running on the tester clock 104) that receives a series of scan-test sequences 102 provided by tester-controlled channels and distributes incoming binary data sequences 112 to m different scan chains 120, each having n registers (not shown in FIG. 1) and (ii) a compactor 130 that receives outgoing binary data sequences 122 from the scan chains 120 and generates a corresponding series of scan-test results 132 that can be analyzed by off-chip tester equipment (not shown in FIG. 1) to detect structural faults and delay faults in the logic under test.
During the shift phase of each cycle of scan testing, the first register in each scan chain 120 is configured to receive its data input 112 from the decompressor 110 and each other register in each scan chain 120 is configured to receive its data input from the previous register in the corresponding scan chain 120. During the capture phase, each register is configured to receive its data input from the IC's functional logic, which can be either combinational logic or sequential logic.
For a given cycle of scan testing, a set of the incoming binary data sequences 112 are clocked into the registers of the scan chains 120 during the shift phase using the slow tester clock, such that, at the end of the shift phase, each register stores a different bit of a corresponding data sequence 112.
At the transition from the end of the shift phase and the beginning of the capture phase, the registers are re-configured to receive their data inputs from the functional logic.
During the capture phase, the binary output data from the functional logic, i.e., the results generated by applying the incoming data sequences 112 to the functional logic, are stored in the registers of the scan chains 120 using two pulses of the fast at-speed clock: (i) a launch pulse to move data d of each launch register to its output q to be applied to functional logic that generates the input d for each capture register and (ii) a capture pulse to move data d of each capture register to its output q. The launch registers are those registers of the scan chains 120 that provide input test data to the functional logic, while the capture registers are those registers of the scan chains 120 that receive corresponding output test data from the functional logic. A launch register can also be a capture register for some part of the testing of the functional logic, and a capture register can be a launch register for some other part of the testing of the functional logic.
During the shift phase of the next scan-testing cycle, as the binary data for the next set of test sequences 112 from the decompressor 110 are shifted into the registers of the scan chains 120, the test results 122 from the previous scan-testing cycle are shifted out of those registers into the compactor 130.
Since the ATPG tool might not be able to provide clocks in the range of hundreds of MHz or even GHz at which modern SoCs work, OCC controller circuitry typically is used to extract from OCC sources such as phase-locked loops (PLLs) using pre-programmed registers (i.e., OCC configuration bits) the at-speed launch and capture pulses of the capture phase. The circuitry used for such purpose is put out of scan in at-speed mode to preserve pre-programmed values.
FIGS. 2A and 2B are schematic block diagrams of each scan chain 120 of the scan-testing circuitry 100 of FIG. 1, in which each scan chain 120 has five registers 230(1)-230(5) stitched together. Note that, in a typical real-world implementation, each scan chain 120 would have many more than just five registers 230. In particular, FIG. 2A shows the scan chain 120 configured for the shift phase of scan testing, while FIG. 2B shows the same scan chain 120 configured for the capture phase of at-speed scan testing.
In both FIGS. 2A and 2B, the scan-data input (sdi) port of the first register 230(1) is connected to receive the decompressor output data 112, each sdi port of every other register 230 is connected to the scan-data output (sdo) port of the previous register 230, and the sdo port of the last register 230(5) is connected to transmit the compactor input data 122. The scan enable (se) port of each register 230 receives a top-level scan-enable control signal 202 that is typically applied to the IC by the ATPG tool, and the clock (ck) port of each register 230 is connected to the clock output (ck_out) port of a clock gate 220.
The clock input (ck_in) of the clock gate 220 is connected to the output 206 of a (2×1) clock multiplexer (mux) 204 that receives, at its two inputs, (i) the relatively slow, tester clock from the ATPG tool and (ii) the relatively fast, at-speed clock from the OCC circuitry. The clock mux 204 also receives a clock-select control signal 208 that determines whether the tester clock or the at-speed clock is applied as the clock signal 206 to the ck_in port of the clock gate 220. The clock-select control signal 208 depends on the type of tests being run on the logic under test. For DC faults, like stuck-at faults, the mux select is constant 1, and the slow tester clock is the clock source for both the shift and capture phases. For AC faults, like delay faults, the clock-select control signal 208 switches from 1 to 0 while moving from the shift phase to the capture phase in order to switch from the slow tester clock to the fast at-speed clock.
As also shown in FIGS. 2A and 2B, the clock enable (ck_en) input of the clock gate 220 is connected to the output 214 of a (2×1) data mux 212 that receives, at its two input ports, (i) a constant 1 to make the clock gate transparent during the shift phase (ii) the logical AND of the enable from OCC configuration registers and the enable for the clock domain from an AND gate 210. The data mux 212 also receives the scan-enable control signal 202 as a data-select control signal.
The q data outputs of the first and second registers 230(1) and 230(2) are shown connected to the IC's functional logic 240, and the d data input of the fourth register 230(4) is shown connected to the functional logic 240. Although not explicitly represented, the d data input and the q data output of each register 230 may be connected to the functional logic 240.
When the top-level scan-enable control signal 202 is high (i.e., logic 1), each register 230 is configured in its shift configuration in which the data appearing at the sdi input port is forwarded to the sdo and q outputs as the register 230 is clocked. When the top-level scan-enable control signal 202 is low (i.e., zero or ground value), each register 230 is configured in its capture configuration in which the data appearing at the d input port is forwarded to the sdo and q output ports as the register 230 is clocked.
As shown in FIG. 2A, during the shift phase of scan testing, (i) the clock signal 206 applied to the ck_in port of the clock gate 220 is the slow tester clock received from the off-chip tester equipment and (ii) the top-level scan-enable control signal 202 is high (i.e., logic value 1), which configures each register 230 to accept the input data applied to its sdi data input port at each clock cycle. Note that the top-level scan-enable control signal 202 is also applied to the clock enable (ck_en) port of the clock gate 220, such that, when the top-level scan-enable control signal 202 is high, the tester clock is applied as the clock signal 222 to the ck clock ports of the registers 230. As such, during the shift phase, the data appearing az the sdi data input of each register 230 is presented at both the sdo and the q data outputs, but the data applied at only the sdi data inputs are shifted into the registers 230, thereby simultaneously shifting data into and out of the registers 230 during the shift phase.
As shown in FIG. 2B, during the capture phase of at-speed scan testing, (i) the clock signal 206 applied to the ck_in input of the clock gate 220 is the fast at-speed clock generated on the IC and (ii) the top-level scan-enable control signal 202 is low, which configures each register 230 to accept the input data applied to its d data input at each clock cycle.
Note that a different clock-enable control signal 206 generated by an on-chip OCC controller (not shown) is applied to the ck_en input of the clock gate 220, such that, when the clock-enable control signal 206 is high, the at-speed clock is applied as the clock signal 222 to the ck clock ports of the registers 230. The on-chip OCC controller generates the clock-enable control signal 206 to allow only two pulses of the at-speed clock (i.e., the launch pulse and the capture pulse) to be applied to the registers 230 during the capture phase.
As such, during the two pulses of the capture phase, the data appearing at the d input of each register 230 is presented at both the sdo and the q data outputs, but the data applied at only the d inputs are stored into the registers 230, thereby moving the output data from the functional logic 240 into the registers 230 during the capture phase.
FIG. 3 is a schematic circuit diagram one of the registers 230 of FIGS. 2A and 2B. The register 230 has a (2×1) input multiplexer (mux) 310, a master latch 320, and a slave latch 330, where the master latch 320 has two transmission gates TG1 and TG2 and two inverters INV1 and INV2, and the slave larch 330 also has two transmission gates TG3 and TG4 and two inverters INV3 and INV4. Note that the transmission gates TG1 and TG4 turn on when the clock signal ck goes low and turn off when the clock signal ck goes high, while the transmission gates TG2 and TG3 turn on when the clock signal ck goes high and turn off when the clock signal ck goes low.
When the top-level scan-enable (se) control signal 202 is high, the mux 310 applies the sdi data signal to the first transmission gate TG1 of the master latch 320, and, when the se control signal 202 is low, the mux 310 applies the d data signal to the first transmission gate TG1. Either way, as the clock signal ck cycles, the applied data signal is latched first into the master latch 320 during the low portion of a clock cycle and then into the slave latch 330 during the high portion of that same clock cycle.
The switching of clocks from the slow tester clock used during each shift phase to the fast at-speed clock used during the subsequent capture phase introduces a "dead time" between the end of the shift-phase clock pulses and the beginning of the two capture-phase clock pulses. Since activity is substantially nonexistent during this period, the on-chip regulator can go into a "cold" state as current demand drops during the dead time. The arrival of the launch and capture pulses causes a sudden increase in current demand due to the logic operating at full speed during the capture phase. The on-chip regulator might not be able to provide sufficient current during this time (as regulator bandwidth might not be sufficient to respond quickly to this current demand), and this can cause a momentary supply drop, which can lead to false negative scan-testing results, where increased register delay (due to voltage drop) is misinterpreted as functional logic failure.
FIG. 4 is a timing diagram showing waveforms for the top level scan-enable control signal 202, the clock-enable signal ck_en of the clock gate 220, the clock signal 222 applied to the registers 230, and the power supply positive rail voltage for the conventional scan-testing circuitry 100 of FIGS. 1-3. As represented in FIG. 4, from time t0 to time t1, the scan testing is in shift phase, and from time t1 to time t4, the scan testing is in the capture phase.
In particular, from time t0 to time t1 of the shift phase, the slow tester clock pulses are applied to the registers 230 as the clock signal 222. At time t1, after the last tester clock pulse is applied, the scan-enable control signal 202 is driven low, thereby ending the shift phase and beginning the capture phase. At the same time, the clock enable signal ck_en is driven low, thereby ceasing to apply any clock pulses to the registers 230.
During the time period from time t1 to time t2, the clock signal 206 applied to ck_in port of the clock gate 220 is switched from the slow tester clock to the fast at-speed clock. During that time period, no clock pulses are applied to the registers 230 and, due to the inactivity in most of the logic under test (only the OCC circuitry contributes to activity which is almost nil in comparison to the shift phase activity), the power supply positive rail voltage begins to droop. A clock cycle before time t2, the clock enable signal ck_en is driven high such that the at-speed launch and capture pulses in the clock signal 222 are applied to the registers 230 at time t2 and time t3, respectively. During that time period, the power supply positive rail voltage drops significantly, which can cause increased register delay that can be misinterpreted as failures in the functional logic 240. Accordingly, it would be advantageous to have circuitry that prevents sudden increases in current demand and thereby prevents corruption of the scan testing.