A biasing circuit with high current drive capability for fast settling of a biasing voltage to a stacked cascode amplifier is presented. According to a first aspect, the biasing circuit uses transistors matched with transistors of the cascode amplifier to generate a boost current during a transition phase that changes the biasing voltage by charging or discharging a capacitor. The boost current is activated during the transition phase and deactivated when a steady-state condition is reached. According to a second aspect, the biasing circuit uses an operational amplifier in a feedback loop that forces a source node of a cascode transistor of a reference circuit, that is a scaled down replica version of the cascode amplifier, to be at a reference voltage. The high gain and high current capability of the operational amplifier, provided by isolating a high frequency signal processed by the cascode amplifier from the reference circuit, allow for a quick settling of the biasing voltage.

In recent years, stacked cascode amplifiers, which use a plurality of transistors arranged as a stack (stacked transistors) in an amplification stage of the amplifiers, have become predominant in radio frequency (RF) applications where high power, high voltage outputs are desired. Due to the higher number of transistors in the stack, voltage handling performance of the amplifier is increased, thereby allowing the high power, high voltage outputs. Stacked or cascoded amplifiers are also common in low noise amplifiers where the benefits to gain an isolation as well as linearity are realized in addition to voltage handling. Since the stacked transistors comprise individual low voltage transistors which can tolerate a voltage substantially lower than the output voltage of the amplifier, it is important to bias the low voltage transistors of the stack so to maintain operation within their tolerable voltage range. Such voltage compliance of the low voltage transistors of the stack must be maintained whether the amplifier operates in an active mode transmitting a signal, or in a standby mode not transmitting a signal. In addition, as performance characteristics of such amplifiers may be based on the biasing voltages to the transistors of the stack, it is important to quickly stabilize such biasing voltages so to reduce a transition phase between different operating modes of the amplifiers. This in turn can allow reduction in settling times of the amplifier when switching, for example, between activated and deactivated states of the amplifier, bands of operation, and/or gain settings of the amplifier, and therefore allow for quicker connections and reduced data loss due to longer settling times of the amplifier.
FIG. 1 shows a simplified schematic of a prior art stacked cascode (RF) amplifier (100). As shown in FIG. 1, the stacked cascode amplifier (100) can comprise a stack of n FET transistors (M1, M2, . . . . , Mn) that include an input transistor M1, and cascode transistors (M2, . . . , Mn), including an output transistor Mn. An input RF signal, RFin, provided at an input terminal of the amplifier (100) is routed to a gate of the input transistor, M1, and is amplified by the amplifier (100). A corresponding amplified output RF signal, RFout, is provided at a drain of the output transistor, Mn, and routed to an output terminal of the amplifier. Decoupling capacitors (Cin, Cout) can be used to decouple low frequency (e.g., DC) biasing voltages provided to the stack of transistors (transistor stack) from the RFin and RFout signals. A supply voltage, VDD, is provided to the drain of the output transistor, Mn, through an inductor, L, and a reference potential (e.g., GND), representing for example an AC ground, is connected to a source of the input transistor M1. In some implementations, as for example described in the above referenced U.S. Patent Publication No. 2018/0083578, the disclosure of which is incorporated herein by reference in its entirety, the source of the input transistor may be optionally connected to the AC ground via degeneration elements, such as, for example, the degeneration inductor Ldeg shown in FIG. 1. A person skilled in the art is well aware of such implementations, as used, for example, in design of low noise amplifiers (LNA's) of a receive path of an RF front end system.
With continued reference to FIG. 1, biasing voltages (Vg2, . . . , Vgn) are provided to gates of the cascode transistors (M2, . . . , Mn) through resistors (R2, . . . , Rn) connected to the gates of the cascode transistors, and a bias voltage Vg1 is provided to the gate of the input transistor M1. Although not shown in FIG. 1, biasing voltage Vg1 may also be provided to the gate of the input transistor via a resistor, as shown, for example, in FIG. 2. Such resistors may be used, in combination with the gate capacitors (Gg2, . . . , Cgn), to decouple any noise from a biasing circuit that generates the biasing voltages into the stacked cascode amplifier and/or decouple any residual RF signal at gates of the cascode transistors (M2, . . . , Mn) from the biasing circuit. Gate capacitors (Cg2, . . . , Ggn) are coupled between gates of the cascode transistors (M2, . . . , Mn) and the reference potential, GND. It should be noted that n is an integer number that can be of any value equal to, or greater than, two. A value of n may be based on a voltage withstand capability of the transistors (M1, M2, . . . , Mn) and a high value of an RF voltage at the drain of the output transistor Mn. More description of such prior art stacked cascode amplifier (100) can be found, for example, in the above referenced U.S. Pat. No. 7,248,120, the disclosure of which is incorporated herein by reference in its entirety.
Biasing voltages to the stacked cascode amplifier (100) of FIG. 1 may be provided by biasing circuits according to various implementations known in the art. Some such biasing circuits are described, for example, in the above referenced U.S. Pat. Nos. 9,843,293, 7,248,120, 9,716,477, and U.S. Patent Publication No. 2018/0083578, the disclosures of which are incorporated herein by reference in their entirety. Also, as described, for example, in the above referenced U.S. Pat. No. 9,716,477, the supply voltage VDD, may be a fixed voltage or a variable voltage. The variable voltage may be provided, for example, via a DC-DC converter or a voltage regulator. In some exemplary configurations, the supply voltage can vary under control of an external control signal. In some configurations, the control signal can be a function of an envelope signal of the input RF signal, RFin, or the output RF signal, RFout. Detailed description of biasing methods and apparatus for stacked transistor amplifiers operating from a variable supply voltage can be found, for example, in the above referenced U.S. Pat. Nos. 9,219,445, and 9,413,298, the disclosures of which are incorporated herein by reference in their entirety.
FIG. 2 shows an exemplary prior art biasing circuit (210) that provides a biasing voltage, Vg2, to the gate of the cascode transistor M2 for an exemplary case of a stacked cascode amplifier (M1, M2) with a non-limiting height of n=2. It should be noted that as discussed above in relation to the stacked cascode amplifier (100) of FIG. 1, such height can be represented by any number n that is equal to, or greater than, two. Accordingly, each of the gate voltages to the cascode transistors (M2, . . . , Mn) may be provided via a biasing circuit that is similar to one depicted in FIG. 2 (e.g., FIG. 5A later described). Also, not shown in FIG. 2, is biasing of the gate of the input transistor, M1, which is beyond the scope of the present disclosure, and which may be provided independently from the biasing voltage Vg2. Some exemplary biasing circuits for biasing the gate of the input transistor, M1, can be found, for example, in the above referenced U.S. Pat. No. 9,716,477 and U.S. Patent Publication No. 2018/0083578, the disclosures of which are incorporated herein by reference in their entirety.
As can be seen in FIG. 2, the biasing circuit (210) comprises a current mirror branch formed by a reference cascode circuit (M′1, M′2) that is a scaled down (e.g., 1/20th or less, such as, for example, 1/30th, 1/40th, . . . , 1/Nth with N≥20) replica version of the cascode amplifier circuit (M1, M2), so that a current (Icore) flowing through the transistors (M′1, M′2) is mirrored to provided a current (Icore*N) flowing thorough the transistors (M1, M2). The transistors M′1 and M′2 are smaller size versions of the transistors M1 and M2 respectively, so that for same biasing voltages applied to the amplifier circuit (M1, M2) and the reference circuit (M′1, M′2), a ratio of the biasing currents through the reference circuit (M′1, M′2) and the amplifier circuit (M1, M2) is substantially equal to a ratio of the sizes of the transistors of the two circuits. Accordingly, if a current Icore flows through the reference circuit (M′1, M′2), then a current Icore*N flows through the amplifier circuit (M1, M2), where N is a ratio of the size of the amplifier circuit to the size of the reference circuit, or in other words, N is a scaling factor between the two circuits. For example, if the transistors M′1, M′2 of the cascode reference circuit (M′1, M′2) are 1/100 of the size of the transistors M1, M2 of the cascode amplifier (M1, M2) respectively, the scaling factor N would be 100. It should be noted that the size of such transistors may be defined in terms of different aspects of the transistors, such as, for example, transistor area, gate length, gate width, etc., so long as a same aspect of the transistors is compared.
With further reference to FIG. 2, gate voltage Vg2 for biasing of the cascode transistor M2 is provided via a combination of a resistive voltage divider (Rtop, Rbot), a diode-connected transistor, M_Diode, and current sources IcasP and IcasN. The current source IcasP is coupled to a common gate-drain node of the diode-connected transistor, M_diode, and the current source IcasN is coupled to a source node of the diode-connected transistor, M_diode. The resistive voltage divider (Rtop, Rbot) generates a reference voltage, Vref2, at the source node of the diode-connected transistor, M_diode, based on a supply voltage VDD. In turn, the diode-connected transistor, M_diode, generates the gate voltage, Vg2, that is one diode drop above the reference voltage, Vref2. Finally, current from IcasP or IcasN serve to provide a current for the diode connected transistor M_diode and also charge or discharge the Vg2 node such that Vg2 is equal to Vref2+ Vdiode, where Vdiode is the voltage across the diode-connected transistor M_diode.
With continued reference to FIG. 2, by selecting the diode-connected transistor, M_diode, to have a same current density as the cascode transistors M′2 and M2, a person skilled in the art would understand that in a steady-state condition of the circuit shown in FIG. 2, where the reference voltage, Vref2, provided by the resistive voltage divider (Rtop, Rbot) and the gate voltage Vg2 are steady, a gate-to-source voltage, Vgs, of the diode-connected transistor, M_diode, is equal to a gate-to-source voltage, Vgs, of the cascode transistors M′2 and M2. In turn, this allows to precisely set, for example, a drain voltage of the input transistor M1 to be equal to the reference voltage, Vref2. As used herein, and as it is well known to a person skilled in the art, the expression "current density" refers to a ratio of a current through a transistor (e.g., drain current) to a size of the transistor, where the size can be any of a transistor area, a gate length, a gate width, etc.
During the steady-state condition of the circuit shown in FIG. 2, the voltage Vref2 and the voltage Vg2 are substantially fixed, and therefore no current flows into the gate capacitor Cg2 and no current flows from the source of the diode-connected transistor M_diode into the resistive voltage divider (Rtop, Rbot). Accordingly, the currents IcasP and IcanN are equal.
Considering a transition phase of the circuit shown in FIG. 2, defined by a change of the biasing voltage Vg2 corresponding to a desired operation of the cascode amplifier (M1, M2). Such transition phase may correspond to, for example, an activation state of the amplifier after a deactivation state of the amplifier, or a change in a frequency band (and therefore operating frequency) of the amplifier, or a change in a gain of the amplifier. As the reference voltage, Vref2, sets the biasing voltage, Vg2, such transition phase may include changing values of the resistors Rtop and/or Rbot so to change the reference voltage, Vref2. As can be seen in FIG. 2, such resistors may be programmable/settable resistors, either according to discrete values or continuous values. It should be noted that although in the exemplary case of the prior art configuration of FIG. 2, a resistive voltage divider is used to generate the reference voltage, Vref2, a person skilled in the art would know that other circuit implementations may also be used, such as, for example, circuits using an operational amplifier and/or digital-to-analog devices. Furthermore, in a case where the transition phase corresponds to activation of the amplifier after a deactivation, or vice versa, the transition phase may also include activation/deactivation of the current sources (e.g., Icore, IcasP, IcasN) which may have been turned off during the deactivated states of the cascode amplifier (M1, M2) for power conservation purposes.
During the transition phase of the circuit shown in FIG. 2, current from IcasP may flow into the gate capacitor, Cg2, to charge up the capacitor to a new (higher) voltage value of Vg2. Alternatively, a current may flow from the capacitor Cg2 into the diode-connected transistor to discharge the capacitor for a new (lower) voltage value of Vg2. For this, a maximum current available for the charging or discharging of the capacitor Cg2 is provided by the maximum current of the current source IcasP and the maximum current of the current source IcasN respectively. As such maximum currents are set to be sufficiently low so as to not drain substantial power from the supply VDD (and therefore from a battery generating VDD), charging and discharging speed of the capacitor Cg2, and therefore settling time of the amplifier's biasing conditions, may be compromised in favor of lesser power consumption of the circuit. A motivation for the teachings according to the present disclosure is to remove a need for such compromise, and therefore reduce the settling times while maintaining a low power consumption of the circuit.


A leverage accessory for hand-held power drills comprises a lever (10) having a handle (14) at one end and a sharp pointed tip (12) at the other end for plunging (10W) into sheathing (16) attached to the stud or joist (24) being drilled. An instantly repositionable, non-slip contact section (38) connects the lever (10) to the drill body (20) to apply force to the central axis of the drill bit (22). The device can be adapted to existing drill motors (20), and may be made integral to drill motor/lever units (68).

The present invention relates generally to electric power drills, particularly hand-held electric power drills. More particularly the present invention relates to devices for facilitating the use of hand-held electric power drills, and still more particularly to devices which use mechanical advantage to facilitate the use of hand-held electric power drills
Though power drills apply the force to turn the drill bit, the force required to push the drill bit along its longitudinal direction into the object to be drilled is provided by the user. Application of the required forces can be ergonomically difficult, straining and tiring, and result in lower productivity, higher stress and higher cost.
Electricians and plumbers in the construction trades regularly bore holes in studs and joists in order to slide wires and pipes through them. The holes range in size from xc2xd inch to 4 inches, with xc2xe inch and 1 inch most common. A considerable amount of pressure must be consistently applied to the drill motor to bore the hole, and often dozens of holes must be bored during a short period. By the time the actual work of plumbing or wiring can begin, the tradesman is tired from boring labor.
Self-augering drill bits which utilize a center mounted screw device to pull the cutting portion of the drill bit through the material to be bored are available but expensive and difficult or impossible to sharpen. These bits become useless once they strike a nail or screw, breaking off and dulling the cutting tips, requiring their replacement, at high cost. Even self-augering drill bits require a final xe2x80x98pushxe2x80x99 to complete drilling. This push results in a lunging forward as the drill bit breaks through. The device of the present invention increases pressure applied as well as increases control during drilling, eliminating the uncontrolled lunging effect.
Furthermore, holes often need to be drilled in difficult to reach spots, such as overhead, making the ergonomics of applying pressure to the drill even more physically awkward, time and energy consuming, and therefore extremely tiring. The force required to push the drill bit through the bore varies with the size of the hole diameter, type and design of the drill bit being used, blade sharpness, drill speed and material being drilled. In all cases, a consistent pressure applied to the drill bit is desirable. The pressure required to be applied to the drill bit throughout the drilling operation varies widely from no pressure applied, to as much as 50 pounds per square inch directed to the drill bit, applied to the longitudinal axis of the drill bit.
Through the years, various techniques of applying force to a portable drill have been developed, specific to the material and object being drilled, location, ergonomics, etc. Several devices have been patented, utilizing a lever to create force. The methods of creating the force and methods of applying the force to the drill motor significantly differ from those of the present invention.
For instance, U.S. Pat. No. 4,168,926, to Rudolph Belcourt, Sep. 25, 1979, requires access to wrap around the object to be drilled, intended for use on pipes. It is not applicable to the object of this invention because of the requirement of clear access to the object being drilled, cumbersome nature of the chains, and longer time required to set up and complete each drilling operation.
U.S. Pat. No. 5,863,158, to George T. Foshee Jr., Jan. 26, 1999, the user must drill a hole to drill a hole, for attaching a bolt and chain to pull against. Though this device could be used in some applications, it is not practical or advisable to drill two holes in order to drill one.
U.S. Pat. No. 5,445,480, to Denys J. Merriman, Aug. 29, 1995, is appropriate for drilling steel beams, where the material being drilled is comparatively thinner than the materials which are intended to be drilled by the present invention, where the hole must be completed with a limited degree of angular movement of the drill bit. This angular movement would be inappropriate for drilling thicker wood, especially multiple layers or beams. The system of pulling from the opposite side of the material being drilled is unable to be used for drilling into interior corners, and studs and joists where accessibility is limited.
U.S. Pat. No. 4,136,579, to Merle W. Robinson, Jan. 30, 1979, (FIG. 9 shows the Robinson device and is provided to clarify the differences between the present invention and this prior art.) Leverage pressure is created by pushing off an adjacent stud or joist using a rolling bearing 32, and linking the lever through a fixed pivot point 22 on the unit housing. The rolling contact point 32 is intended to roll as it is pushed off the adjacent stud. Its use is optimized for specific 16 inch on center stud and joist spacing. It has minimal provision for adjustment of link 18 to allow for variations in stud and joist spacing and requires an external tool to adjust, which is difficult and time consuming. Because of its limited application, difficulty and limits of adjustment, this prior art accessory did not become commercially accepted.
A leverage accessory for hand-held power drills comprises a lever having a handle at one end and a sharp pointed tip at the other end for plunging into sheathing attached to the stud or joist being drilled. An instantly repositionable, non-slip contact section connects the lever to the drill body to apply force. The device can be adapted to existing drill motors, and may be made integral to drill motor/lever units.
An object of the present invention is to provide for application of mechanical advantage to a hand-held power drill to allow the operator to drill holes in studs and joists in a more efficient and ergonomically satisfactory manner.
Therefore, it is an object of the present invention to provide an apparatus for applying mechanical advantage to the longitudinal force applied to a drill.
It is another object of the present invention to stabilize the position of the drill motor during the drilling process.
More particularly, it is an object of the present invention to provide a means for attachment of a lever to a drill motor to assist in providing a longitudinal force and stabilization of a drill.
Another object of the present invention is to provide flexible adaptability to each new hole boring application without need for complicated adjustment of the tool.
It is also an object of this invention to make said device instant and intuitive for the user, in order to facilitate rapid setup, execution of the drilling operation and removal for repetitive use in the field.
Advantages include improvement of ergonomics, ease of drilling, speed, safety, control and better accessibility to remote locations for drilling in studs and joists.


A system for awarding a progressive prize includes a bank of gaming machines accepting different bets per play as selected by a player. A random number is selected from a predetermined fixed range of numbers that does not change during play of a gaming machine. The player is allotted one or more numbers for each credit bet. The allotted numbers represent a subset of the predetermined fixed range of numbers. A feature game is triggered for the progressive prize based on a numerical comparison between the selected random number and the number(s) allotted to the player. Certain embodiments provide a trigger condition for a feature outcome based on an event having a probability related to credits bet per game at a gaming machine. A probability of success in the feature game may be higher than a probability of success in the base game.

The present invention relates to apparatus for use with a system of linked poker machines and in particular the apparatus provides an improved jackpot mechanism for use with such a poker machine system.
Many schemes have been devised in the past to induce players to play slot machines including schemes such as specifying periods during which jackpot prizes are increased or bonus jackpots paid. Other schemes involve awarding an additional prize to a first player to achieve a predetermined combination on a poker machine. These methods, while effective, add to club overheads because of the need for additional staff to ensure that the scheme is operated smoothly.
More recently, with the advent of poker machines linked through electrical networks it has been possible to automatically generate jackpot prizes on the basis of information received from the machines being played which are connected to the system and one such prior art arrangement, commonly known as "Cashcade™", counts turnover on all machines in the network, increments a prize value in accordance with the turnover and pays the jackpot prize when the count reaches some predetermined and randomly selected number. In a more recent prior art arrangement, each game played on each machine in a gaming system is allocated a randomly selected number and the prize is awarded to a machine when the game number it is allocated matches a preselected random number.
In another recent prior art arrangement, the winning machine is selected by randomly selecting a number at a point in time and decrementing the number as games played on the system are counted until the number is decremented to zero at which time the game (or associated machine) causing the final decrement is awarded the jackpot.
With some prior art combination based trigger arrangements there is a serious disadvantage in that the player betting a single token per line, is just as likely to achieve a jackpot as the player playing multiple tokens per line. This has the effect of encouraging players playing for the bonus jackpot to bet in single tokens, rather than betting multiple tokens per game.
Jackpot games have traditionally been popular in Casinos. However, in their conventional format these games have inherent limitations:
(i) Games which use specific combinations of symbols to trigger jackpots are perceived by many players as being unwinnable. The games are typically designed in such a way that the big jackpots should not be won until large amounts are accumulated. With such low frequency the jackpots are never seen to be won by most players. Anecdotal evidence suggests that many players have learnt to disregard the chance of winning the major jackpots and are realistically playing for the lesser jackpots (i.e. the minor and mini jackpots). The increasing popularity of small mystery jackpots with higher frequencies of occurrence tends to support this argument;
(ii) Due to the increasing demand of players for a more complex and diverse game range, conventional jackpot games with combination triggers have become superseded. However, it is extremely complex to develop a wide variety of combinations which support both a feature game and mathematically exact jackpot triggers;
(iii) Typically, it would be expected that the game return (RTP) is independent of the number of coins bet per line. With conventional progressive jackpot games though, increasing the credits bet per line creates a relative disadvantage as far as RTP is concerned. Let's say the start-up amount for a feature jackpot is $10000. A player who is playing 1 credit per line has a chance for $10000 for each credit played, whereas a player playing 5 credits per line only has a chance for $2000 for each credit played. This creates a scale of diminishing returns. The smart player who gambles for the feature jackpot only, will always cover all playlines, but will only bet 1 credit per line because the prize paid for the feature jackpot is the same irrespective of the bet. This is supported by data collected from casinos;
(iv) Typical combination triggered progressive jackpots have fixed hit rates which removes from the operator's control the ability to vary jackpot frequency.
These arrangements have been in use in the State of New South Wales and in other jurisdictions for a considerable period of time, however, as with other aspects of slot machine games, players become bored with such arrangements and new and more innovative schemes become necessary in order to stimulate player interest.
In this specification, the term "combinations" will be used to refer to the mathematical definition of a particular game. That is to say, the combinations of a game are the probabilities of each possible outcome for that game.

Slot machine game and system with improved jackpot feature

ARISTOCRAT TECHNOLOGIES AUSTRALIA PTY LIMITED


A reaction tube for performing isothermal polymerase chain reaction therein is provided and includes an upper section, a lower capillary section, a linkage connecting the upper section and the lower capillary section, and a thermal conductor. The lower capillary section has an annealing portion, an annular heating groove, and a close end. The annealing portion is connected with the linkage, and the annular heating groove is connected with the annealing portion. The close end is connected with the annular heating groove. The thermal conductor tightly embraces the annular heating groove of the lower capillary section for conducting heat. Accordingly, a heat generated from the heating source will conduct to the annular heating groove of the lower capillary section of the reaction tube, a temperature gradient along the reaction tube is then provided in order to perform a thermal convection, thereby performing the isothermal polymerase chain reaction in the reaction tube.

1. Technical Field
The present disclosure relates to a container for performing nucleic acid amplification reaction therein. More particularly, the present disclosure relates to a reaction tube for performing isothermal polymerase chain reaction therein.
2. Description of Related Art
The nucleic acid amplification reaction is a scientific technique in molecular biology to amplify a single or a few copies of a particular deoxyribonucleic acid (DNA) sequence by repeating the same procedure with particular polymerases. The common techniques such as polymerase chain reaction (PCR), reverse transcription polymerase chain reaction (RT-PCR), and real-time polymerase chain reaction (real-time PCR) all belong to nucleic acid amplification reaction techniques.
The PCR is majorly used to amplify a particular DNA, whereas the RT-PCR is used to reverse transcribing a specified RNA fragment to a particular DNA fragment followed by amplifying the particular DNA fragment, namely complementary DNA (cDNA). The real-time PCR, also called quantitative PCR, is used to amplify and quantify a targeted DNA simultaneously, where the main reagents associated in this procedure are fluorescent probe and dyes. Taking all together, the principle of the nucleic acid amplification reactions mentioned above is PCR.
Furthermore, some skills presented lately also belong to nucleic acid amplification reactions, such as rolling circle amplification (RCA), loop mediated amplification (LAMP), nucleic acid sequence based amplification (NASBA), and three way junction (TWJ).
Regarding to general PCR, the initialization step is used for mixing and heating DNA templates, primers, and a buffer solution to the reaction temperature about 90° C. for disrupting the hydrogen bonds between two single-stranded DNA templates, namely the denaturation step. The second step is used for cooling the reaction temperature to about 50° C. for annealing the primers and the single-stranded DNA template. The final step is used for holding the temperature at about 70° C. for extending the primers. The particular DNA is copied by repeating the above procedure.
The types of the apparatus for the nucleic acid amplification reaction are classified according to the prices. The cheaper type includes a container, such as a tube or a capillary, and two heaters. The two heaters are respectively disposed on the two ends of the container. One heater heats the container to about 90° C., and the other heats the container to about 50° C. The solution convection in the container takes place because of the density difference of the solution at the two ends of the container, wherein the density difference is caused by the temperature difference between the two ends. The DNA and the primers is circulated through the container and heated from 90° C. to 50° C. circularly for performing the nucleic acid amplification reaction.
The heater is made of a metal block. The block has a groove for receiving the end of the container, and the shape of the groove is designed to be fitted to the end of the container. However, the groove does not completely match with the container; it implies that the groove remains some protrusions and indentations when the end of the container is received by the groove. Therefore, the edge of the protrusions and the indentations do not completely and evenly contact to the container in order to conduct heat to the container. Thus, the container cannot be heated evenly. The reaction efficiency of the nucleic acid amplification reaction will be reduced.

Reaction tube for performing isothermal polymerase chain reaction therein


The present invention provides a finalization method and apparatus which enables out a reproduction of an optical disk such as a DVD-RAM by using a reproduction apparatus which carries out CLV reproduction. The finalization method according to the present invention includes creating an unrecorded area map of an optical disk on the Logical block address (LBA). In order to execute in the host application a conversion from LBA to Physical Block Address (PBA) which is normally executed in an optical disk drive, a conversion table from LBA to PBA is created. According to this conversion table, the unrecorded area map is converted from LBA into PBA so as to assure the area to be finalized. A dummy data is recorded in the aforementioned assured area of the optical disk.

1. Field of the Invention
The present invention relates to an optical disk recording method and more particularly, to an optical disk finalization method and an optical disk finalization apparatus.
2. Description of the Prior Art
In an optical disk capable of recording and reproduction, a wobbled groove guide is formed so as to enable tracking control even in a state of no data recorded. As shown in FIG. 1, this wobbled groove guide draws a sinusoidal wave pattern on a track of a substrate of the optical disk. An optical disk drive obtains a servo information from an edge of this wobbled groove guide for reproducing a data recorded on the optical disk. Moreover, the wobbled groove guide which is the sinusoidal wave pattern has been subjected to a frequency modulation corresponding to an address information. According to an address (address in pregroove which will be referred to as ADIP hereinafter) assigned for this wobbled groove guide, the optical disk drive detects a position information on the optical disk for reading a signal from the optical disk and for writing a signal onto the optical disk.
Consequently, the aforementioned optical disk capable of both recording and reproduction can record and reproduce a signal by using a recording reproduction apparatus provided with a circuit for reading the ADIP (hereinafter, referred to as ADIP-reader) even if a data is recorded not sequentially but intermittently.
There is also an optical disk reproduction apparatus which is dedicated to reproducing a sequentially recorded data and which is not provided with the aforementioned ADIP-reader. Such a reproduction apparatus controls the rotation of an optical disk by reproducing a recorded data and carrying out a so-called CLV (constant linear velocity) control to a spindle motor so that a clock extracted from the reproduced data has a constant cycle.
Consequently, in order to reproduce the aforementioned optical disk capable of both recording and reproduction by the reproduction apparatus which carries out this CLV reproduction, what is required is that the optical disk have a data formatted in a common format and the data be recorded sequentially.
However, even when reproducing the aforementioned optical disk capable of both recording and reproduction by using a reproduction apparatus which carries out CLV reproduction, this optical disk cannot be reproduced if the data is recorded not sequentially but intermittently. That is, a data reproduction by way of CLV reproduction brings about only a partial data reproduction and accordingly, it is impossible to reproduce a clock. Consequently, the reproduction apparatus which carries out a CLV reproduction cannot control rotation of the optical disk and the spindle motor runs away in the worst case.

Optical disk finalization method and optical disk finalization apparatus


Embodiments of the present invention generally relate to a method for cleaning a processing chamber during substrate processing. During a first substrate processing step, a plasma is formed from a gas mixture of argon, helium, and hydrogen in the processing chamber. In a second substrate processing step, an argon plasma is formed in the processing chamber.

1. Field of the Invention
Embodiments of the present invention generally relate to a method for reducing particle deposition and cleaning a chamber while processing a substrate. More specifically, embodiments of the present invention relate to an in situ chamber clean with an inert hydrogen helium mixture during wafer processing.
2. Description of the Related Art
During chip packaging, metal layers are used for connecting solder material to bond pads that are electrically connected to semiconductor devices. Generally, incoming wafers for under-bump metallization (UBM) processes consist of metal pads embedded in a polymer passivation layer, such as a polyimide layer. The metal pads, such as aluminum pads, must be cleaned prior to UBM to remove any native oxide, such as aluminum oxide, from the surface of the metal pads.
FIG. 1A is a prior art schematic view of a packaging preclean process chamber 100. Currently, etching processes are used to remove the native oxide 114 from the surface of the aluminum pads 112. Etching processes generally utilize a halogen plasma 106, such as an argon plasma, to bombard the surface of a substrate 110 with ions to sputter (remove) undesired material present on the surface of the substrate 110. The etching removes native oxide 114, which generally reduces electrical conductivity, from the surface of the aluminum pads 112 but also sputters 118 the polymer layer 116 which re-deposits on interior surfaces 104 of the semiconductor processing chamber kit 102. The re-deposited polymer 108 on the interior surfaces 104 increases the presence of particles in the chamber which may lead to undesirable contamination of the substrate 110 and increase the defectivity of the packaging preclean process.
Generally, the polymer sputtered on the interior surfaces of the chamber kit is pasted over with an aluminum paste to reduce the presence of particle contaminants in the chamber. However, aluminum pasting in the chamber is time consuming and decreases throughput because a substrate is generally not present in the chamber during the pasting process. Therefore, it is desirable to reduce the amount of polymer re-deposited on the interior surfaces of the chamber. Providing oxygen plasma to the chamber to perform an ashing process is effective at removing the polymer from the interior surfaces of the chamber but the presence of oxygen in the chamber will cause oxidation of the metal pad, creating undesirable native oxide thereon as previously discussed. Therefore, a substrate cannot be processed while performing an ashing process, which reduces throughput.
Accordingly, what is needed in the art is a method of reducing polymer deposits on the interior surfaces of a processing chamber that does not promote the formation of native oxide and reduces the frequency of aluminum pasting to cover the re-deposited polymer on the interior surfaces of the chamber.

In situ chamber clean with inert hydrogen helium mixture during wafer process


A combination system including a plurality of reproducing apparatuses, such as a digital versatile disk player (DVDP) and a video cassette recorder, and a method for controlling operation of the same. The combination unit includes a selecting unit for selecting a reproduced signal provided by one of the plurality of reproducing apparatuses that is switched to a play mode, a selection information storing unit for storing selection information identifying the reproducing apparatus that outputs the reproduced signal selected by the selecting unit, and a control unit for controlling the reproducing apparatus to switch to a pause mode or a stop mode when the selection information stored in the selection information storing unit changes from identifying the reproducing apparatus to identifying another reproducing apparatus of the plurality of reproducing apparatuses. The control unit can be disposed in one of the plurality of the reproducing apparatuses, and can control that reproducing apparatus to switch from the pause mode into the stop mode when the selection information stored in the selection information storing unit is not changed for a predetermined time period. Accordingly, the operability of the combination system improves, while undesired power consumption due to unnecessary reproducing operation of the reproducing apparatus can be prevented.

1. Field of the Invention
The present invention relates to a system and method for combining a plurality of reproducing apparatuses in a single unit. More particularly, the present invention relates to a system for combining a plurality of devices, such as digital versatile disk players and videocassette recorders, in a single unit, and a method for controlling operation of the same.
2. Description of the Related Art
FIG. 1 shows a combined DVDP/VCR system 10 and its associated peripherals connected. The combined DVDP/VCR system 10 has a video cassette recorder (VCR) unit 11 for performing functions of the VCR such as reproducing video and audio from a magnetic tape and recording an externally received signal onto the magnetic tape, and a digital versatile disk player (DVDP) unit 12 for performing functions of the DVDP such as reproducing video and audio from a DVD. In addition to the separate functions of the VCR unit 11 and the DVDP unit 12, the combined DVDP/VCR system 10 also has the combined functions such as recording the video and audio reproduced from the DVDP unit 12 onto the magnetic tape by the VCR unit 11.
The combined DVDP/VCR system 10 is connected to a television 23 for outputting the video and audio reproduced from the DVDP unit 12 or from the VCR unit 11, and is also connected to an audio amp 21 for outputting the audio signal reproduced from the DVDP unit 12. In addition, the combined DVDP/VCR system 10 can be connected to external devices 25 such as a camcorder, and therefore, the combined DVDP/VCR system 10 performs recording and reproducing of the video and audio input from the external devices 25.
The VCR unit 11 and the DVDP unit 12 of the combined DVDP/VCR system 10 are constructed as one system. Hence, a user can switch the modes of the VCR unit 11 and the DVDP unit 12, and manipulate the respective functions of the VCR unit 11 and the DVDP unit 12 by manipulating a separate input device such as a remote controller 15, or by manipulating an operational panel (not shown) provided with the combined DVDP/VCR system 10.
In the conventional combined DVDP/VCR system 10 constructed as described above, video and audio signals are output through a display unit (e.g., television) by a reproducing operation performed by the VCR unit 11 or the DVDP unit 12. When one of the units 11 or 12 is performing a reproducing operation and the user wants the other unit 11 or 12 to perform the reproducing operation instead, he or she has to switch the play mode of the reproducing unit 11 or 12 to a stop mode, and then switch the mode of the other unit 11 or 12 to the play mode, which is quite complicated.
Japanese Patent No. 7-312071 to Matsushita Electric Ind. Co., Ltd., the entire contents of which is incorporated by reference herein, discloses a Reproducing device which includes a combination apparatus having improved operability, in an attempt to solve the above problems.
FIG. 2 shows the reproducing device disclosed in JP 7-312071, which includes a VCR unit 11A, a DVDP unit 12A, an input unit 20 for selecting the VCR unit 11A or the DVDP unit 12A to operate in a play mode, and an output determining unit 30 for controlling the selected unit 11A or 12A to operate in the play mode. The reproducing device further includes an output selecting unit 40 for selecting the VCR unit 11A or the DVDP unit 12A to operate in the play mode under the control of the output determining unit 30, and a display unit 50 for displaying an output signal reproduced by the unit 11A or 12A that is selected by the output selecting unit 40.
For example, when the user inputs a VCR reproducing command through the input unit 20 during the reproducing operation of the DVDP unit 12A, the output determining unit 30 controls the VCR unit 11A to perform a reproducing operation, while controlling the DVDP unit 12A to stop the reproducing operation. The output selecting unit 40 selects the output signal reproduced from the VCR unit 11A and outputs the selected output signal to the display unit 50.
In other words, the device disclosed in JP 7-312071 provides improved operability for the case where the user inputs through the input unit 20 a command for reproducing operation of the other unit during the reproducing operation of one unit, by preferentially switching the mode of the other unit into a play mode and outputting the reproduced signal through the display unit 50.
The combination apparatus disclosed in JP7-312071 also provides improved operability, especially when the unit is made to switch to the play mode through the input unit 20. However, the improvement in operability does not occur when the unit is made to switch to the play mode upon insertion of a recording medium, namely, a video tape or DVD, into a deck (not shown).
For example, in the case where the DVDP unit 12A is switched to the play mode due to insertion of the DVD in the deck when a reproducing operation is being performed by the VCR unit 11A, the output determining unit 30 cannot determine whether the DVDP unit 12A is switched to the play mode or not, and accordingly, the VCR unit 11A keeps operating in the play mode. Therefore, the user has to separately input the stop command for the DVDP unit 12A through the input unit 20, or stop the operation of the DVDP unit 12A by taking the DVD out of the deck.
Furthermore, when the user needs to switch the DVDP unit 12A to the play mode to search the recorded contents on the DVD when a reproducing operation is being performed by the VCR unit 11A, the user has to switch the VCR unit 11A to the stop mode, and then switch the DVDP unit 12A to the play mode. The user also has to switch the VCR unit 11A back to the play mode after the completion of search, which results in inconvenience for the user.

Combination system having a plurality of reproducing apparatuses and a method for controlling operation thereof


A condensate extractor system for an internal combustion engine assembly with a charge air cooler system is provided. The condensate extractor system includes a hose member with a first end in direct fluid communication with the charge air cooler system, and a second end in direct fluid communication with the intake manifold of the engine air intake system. The hose member removes condensate from the charge air cooler system in a continuous manner in response to a pressure gradient created by the throttle body when the engine is in an on-state. The hose member defines an orifice configured to restrict the flow of air and condensate through the hose member. A filter is placed in direct fluid communication with the hose member, upstream from the orifice. The hose member is preferably characterized by a lack of fluid communication with a reservoir configured to collect condensate.

Internal combustion engines (ICE) are often called upon to generate considerable levels of power for prolonged periods of time on a dependable basis. Many such ICE assemblies employ a mechanical supercharging device, such as a turbocharger (or turbine driven, forced induction supercharger), to compress the airflow before it enters the intake manifold of the engine in order to increase power and efficiency. Specifically, a turbocharger is a gas compressor that forces more air and, thus, more oxygen into the combustion chambers of the ICE than is otherwise achievable with ambient atmospheric pressure. The additional mass of oxygen-containing air that is forced into the ICE improves the engine's volumetric efficiency, allowing it to burn more fuel in a given cycle, and thereby produce more power.
Under extreme operating conditions, the "supercharging" process may elevate the temperatures of the intake air to an extent that causes the formation of undesired exhaust by-products, such as various nitrogen oxides (NOx), and reduces the density of the air charge. To combat this problem, ICE manufacturers have historically employed a device most commonly known as an intercooler, but more appropriately identified as a charge-air-cooler (CAC) or aftercooler, to extract heat from the air exiting the supercharging device. A CAC is a heat exchange device used to cool the air charge and, thus, further improve volumetric efficiency of the ICE by increasing intake air charge density through isochoric cooling. A decrease in air intake temperature provides a denser intake charge to the engine and allows more air and fuel to be combusted per engine cycle, increasing the output of the engine.
The heat exchange process can cause moisture (water) to condense and, thus, form inside of the CAC system, especially when conducted in conditions where the ambient air flowing through the supercharging device and CAC is substantially humid (e.g., greater than 50% relative humidity). The condensation tends to accumulate downstream from the CAC, within the conduit through which the intake manifold receives the supercharged airflow. The liquefied condensation can be drawn into the intake manifold, entering the various cylinder combustion chambers. Depending upon the configuration of the CAC and supercharging devices, as well as their individual and relative packaging, the condensation may begin to puddle and enter the combustion chambers in large amounts, potentially causing the ICE to misfire, leading to premature engine wear, and creating a false-positive error signal triggering a service engine indicator light. In addition, accumulated water condensate that is not properly evacuated from the CAC can freeze and crack the CAC when ambient temperatures reach below freezing.

This patent is subject to a terminal disclaimer.

Condensate extractor for charge air cooler systems


There is disclosed vehicle mounted apparatus for broadcasting a warning signal on a radio channel to thereby warn of the vehicle's approach. The apparatus includes a transmitter for broadcasting a warning signal on a radio channel, and a controller for controlling the strength of the broadcast warning signal on the basis of a signal strength of a normal signal on the radio channel to thereby control a broadcast range of the warning signal.

Currently emergency vehicles operate a warning siren in order to warn people that the emergency vehicle is approaching so that those persons can take such action as is necessary to get out of the path of the emergency vehicle. Recent car design has improved sound deadening to isolate passengers from other noise. This makes it more difficult for drivers and/or passengers to hear a siren. Further, there is now wide spread use of sound systems in motor vehicles and a tendency for persons to listen to their sound systems at high volume levels which can make it difficult for them to hear a warning siren. Hence, audible warning devices used by emergency vehicles have become less effective.
U.S. Pat. No. 4,296,496 proposes a radio warning device for broadcasting a warning signal which can be received by radios in vehicles in the immediate area.
U.S. Pat. No. 5,889,475 proposes a system in which a radio signal transmitted by a moving vehicle is used to activate an AM/FM transmitter located at an intersection. Once activated, the transmitter broadcasts a warning signal which can be received by a vehicle's radio.
An inherent problem with such systems is that the warning signal will be received by radio receivers of people who do not need to receive the warning signal. While this cannot be avoided entirely, it would be advantageous to provide apparatus which aims to minimize the extent to which people who do not need to receive the warning signal are inconvenienced.

Apparatus for broadcasting a warning signal


A security element for an object of value has a flat, transparent body with a front side and a back side between which there lies a center plane, a first region configured on the body and a second region configured on the body which encode a motif. The body has in the first region a ground element structure which conveys different color impressions from front and back sides in plan view of the body. The body likewise has the ground element structure in the second region and is in mirrored form relative to the center plane, causing first and second regions to show the motif from both sides in plan view, and the motif to be unrecognizable in transmission view.

This invention relates to a security element for an object of value, said element having a flat, transparent body with a front side and a back side between which there lies a center plane, a first region configured on the body and a second region configured on the body which encode a motif, said body having in the first region a ground element structure which conveys different color impressions from front and back sides in plan view of the body.
Security elements of value documents having periodic line gratings are known, for example from DE 102009012299 A1, DE 102009012300 A1 or DE 102009056933 A1. They can have color filter properties in the subwavelength region when the grating is so designed with regard to the grating profile that resonance effects occur in the visible wavelength region. Such color filter properties are known both for reflective and for transmissive subwavelength structures. Said structures have a strongly polarizing influence on the reflection or the transmission of an incident light ray. The color is relatively strongly dependent on angle in reflection or transmission of such subwavelength gratings. However, the color saturation is considerably weakened for said gratings when the incident light is unpolarized.
There is known a line grating having subwavelength structures which possesses angular-dependent, color-filtering properties. The line grating possesses a rectangular profile made of a dielectric material. The horizontal surfaces are overlaid with a high-refractive dielectric. Above this structure there is likewise located a dielectric material, with the refractive indices of the grating substrate and of the cover material preferably being identical. As a result there is formed an optically active structure consisting of two gratings made of the high-refractive material which are spaced by the height of the original rectangular profile. The grating ridges forming the line grating are made for example of ZnS. There can be produced therewith a color contrast in reflection, but in transmission a change of color tone for different angles is hardly perceptible. This structure is therefore only useful as a security feature in reflection and must be constructed on an absorbent ground for that purpose.
Two-dimensionally periodic hole structures are described in the scientific literature that have filter properties of the incident light in the subwavelength region. In this connection, reference is made to the following literature sources: T. W: Ebbesen et al., "Extraordinary optical transmission through sub-wavelength hole arrays", Nature, 667-669 (1998); L. Martin-Moreno et al., "Theory of extraordinary optical transmission through subwavelength hole arrays", Phys. Rev. Lett. 86(6), 1114-1117 (2001); W. L. Barnes et al., "Surface plasmon subwavelength optics", Nature, Vol 424, Issue 6950, pp. 824-830 (2003); J. Bravo-Abad et al., "How light emerges from an illuminated array of subwavelength holes", Nature Physics 1, 120-123 (2006); H. S. Lee et al., "Color filter based on a subwavelength patterned metal grating", Opt. Express 15, 15457-15463 (2007); C.-P. Huang et al., "Dual effect of surface plasmons in light transmission through perforated metal films", Phys. Rev. B 75, 245421 (2007). Such so-called hole arrays consist of thin opaque metal films.
DE 102007016394 A1 proposes employing such structures as security elements in value documents for authenticating genuineness.
Further, two-dimensionally periodic gratings are known that allow a color filtering in primary colors, red, green, blue, with high color saturation over a relatively great viewing-angle range. The publication B.-H. Cheong et al., "High angular tolerant color filter using subwavelength grating", Appl. Phys. Lett. 94, 213104 (2009) describes a grating with cube-shaped elevations which has a pronounced band-pass filter characteristic. The elevations are made of amorphous silicon and located on a glass substrate. A replication method for such gratings is presented in the publications E.-H. Cho et al., "Two-dimensional photonic crystal color filter development", Opt. Express 17, 8621-8629 (2009) and E.-H. Cho et al., "Nanoimprinted photonic crystal color filters for solar-powered reflective displays", Opt. Express 18, 27712-27722 (2010).
The prior art further includes WO 2003/070482 A1, WO 2011/032665 A1, WO 2011/082761 A1, WO 2011/066992 A1, EP 2228671 A1. The publications R. J. Potton, "Reciprocity in optics", Rep. Prog. Phys. 67, 717 (2004); R. Petit, "Electromagnetic theory of gratings", Vol 22 of Topics in current physics, Springer-Verlag (1980), explain the principle of reciprocity in optics, in particular for gratings.
The grating structures from the prior art can be employed for security elements for protecting value documents, since they provide a color effect in plan view that is not reproducible by conventional copying methods. The angle dependency of the color effect is especially advantageous therefor.

Security element having a color-effect-producing structure


A protection circuit prevents a surge applied to one end of a signal line from being applied to a circuit connected to another end of the signal line. The protection circuit includes a first diode having an anode coupled to the signal line and a first capacitor having a first electrode coupled to a cathode of the first diode and a second electrode coupled to a first potential. A second capacitor has a first electrode coupled to the signal line and a second diode has a cathode coupled to a second electrode of said second capacitor and an anode coupled to the first potential. A first inductor is coupled between the cathode of the first diode and the cathode of the second diode. A power supply terminal is applied with a power supply potential and is coupled to one end of the first inductor.

1. Technical Field
The present invention generally relates to a protection circuit for preventing voltage surges from being applied to a circuit and, more particularly, to such a protection circuit incorporated in a node (such as a line extender or a distribution amplifier) of a broadcast distribution system.
2. Description of Related Art
Broadband community area or cable television (CATV) systems have been designed with a system architecture known as "mink and feeder." The function of a trunk coaxial cable is to deliver broadband television signals from a reception center, or headend, over the shortest distance with the least amount of amplification to a plurality of distribution points. The distribution points are connected to feeder coaxial cables which emanate from the trunk coaxial cable and contain subscriber tap off devices. The broadband television signals are transmitted over the distribution network from the headend in a forward direction to a plurality of subscribers, which is generally termed a one-way system. However, more complex systems include a reverse signal path. The reverse channel is used for system control, messaging, pay-per-view events, monitoring, and the like.
As the signal travels down the feeder cable and through successive tap off devices, loss is incurred and the power level becomes progressively lower. If the last subscriber is reached before the signal level drops below the minimum tap port level set for the system, the feeder can be terminated and no additional devices are required. If, however, the signal level drops below the minimum required tap port level before the last subscriber (or subscribers) is reached, it is necessary to amplify the signal with a line extender amplifier before the feeder path can be continued. After amplification and equalization, the feeder is continued.
FIG. 1 is a general block diagram of a line extender which is usable in a television distribution system. Forward path communication signals (e.g., in a frequency range of 50-860 Megahertz) from a coaxial cable are supplied via a capacitor 101 to a diplex filter 103. Diplex filter 103 provides these forward path communication signals to a series of amplifiers 105, 107, 109, and 111. Amplifiers 105, 107, 109, and 111 may, for example, be Gallium Arsenide (GaAs) Field Effect Transistor (FET) amplifier circuits. Equalization circuits 113 and 115 are provided to equalize the forward path communication signals. In one implementation, equalization circuit 113 may be a plug-in circuit so that different circuits may be easily incorporated into the line extender depending on the signal characteristics at the particular location of the line extender. The output of amplifier 111 is supplied to a diplex filter 117 and output to the distribution network via a capacitor 118. Reverse path communication signals (e.g., in a frequency range of 4-160 Megahertz) are supplied to diplex filter 117 via capacitor 118. These signals are then provided to reverse path amplifier 119. The output of reverse path amplifier 119 is supplied to the distribution system via diplex filter 103 and capacitor 101. AC power (60 Volts, 60 Hertz) or higher, passes through a path including inductors 121 and 123. Jumper Connectors 125 and 127 are provided to direct power flow through the amplifier housing as required by the system's architecture.
Three types of signals (i.e., forward path communications signals, reverse path communication signals, and AC power) are present in line extenders such as the line extender of FIG. 1, as well as in other amplifiers in the television distribution network. Voltage surges associated with any of these signals can cause damage to the active components of the line extenders and other amplifiers, especially during installation procedures or during "hot coring." (Hot coring is the procedure of striping out the outer conductor of a coaxial line using a conductive blade, while AC power is present.) In particular, damage of amplifiers 109 and 111 shown in FIG. 1 has been observed when a coaxial cable of the distribution system is connected to the output terminal for the forward path amplifiers of line extenders. This damage is caused by high frequency surges generated by the arcing which occurs as the connection or disconnection is made. While various surge protection circuits are known, these circuits generally utilize one or more capacitors in the signal path, thereby resulting in a DC disconnection in the signal path. Such a DC disconnection can in some cases disrupt the biasing of the amplifiers. In order to provide protection against surges of both positive and negative polarities, surge protection circuits generally require the use of two power supplies (e.g., a positive and a negative power supply). The need for two power supplies increases the costs associated with the line extenders. Protection circuits which do not require biasing operate either at low level (system inputs) or at considerably high levels which are beyond the damage threshold of the GaAs FETs. Such circuits are also generally slow in responding to such surges.
Accordingly, it would be desirable to provide a protection circuit which overcomes these and other disadvantages of prior systems.

Protection circuit and a node for a communications system using the protection circuit


A cable connector comprises a housing formed with a main body and a mating portion forwardly extending from the main body and a plurality of contacts. The main body and the mating portion are formed with a plurality of ribs, every two adjacent ribs defining a slot. The contacts received in the slots, the contact has at least one signal contacts, the signal contact is formed with a mounting portion located in the main body and two parallel contacting arms extending forwardly from a front end of the mounting portion and located in the mating portion.

1. Field of the Invention
The present invention relates to a cable connector for electrically connecting cables to a print circuit board.
2. Description of Related Art
Following development of electronic and communication technology, more and more different connectors are widely used for connecting electronic equipments, such as a cable connector, which is used for connecting cables to a print circuit board and builds signal transmission path between the cable and the print circuit board.
A cable connector for connecting cables to a print circuit board include a first connector and a second connector, the first connector comprises an insulating housing with a mating portion, a plurality of piece-like contacts received in the insulating housing and a shell covering the insulating housing. Each contact has a contact portion arranged in an upper surface of the mating portion for connecting with the second connector, and a mounting portion in rear of the contacting portion for soldering with the cables. The second connector has a second housing defining a receiving room for receiving the mating portion and a plurality of terminals arranged on sides of the receiving room. When the first connector engages with the second connector, the first contacts electrically contact with the terminals.
However, the contacts of the first connector includes a plurality of signal contacts and the width of the signal contact is narrow, so the signal contacts can not meet the requirement for high electrical current transmission. Furthermore, it is not easily to solder the cables to the mounting portions of the signal contacts, and the contacting between the contacting portion of the contact and a corresponding terminal is not reliably for the narrow width of the contact.
Hence, an improved cable connector is required to overcome the disadvantages of the prior art.


A container for housing optical instruments is described. The container includes a case having an interior surface shaped to define a container cavity for holding an optical instrument. The interior surface is further shaped to define a plurality of ball-receiving concavities which open into the container cavity. Each ball-receiving concavity is shaped to have an opening at its edge and an interior region. The container also includes a plurality of elastically deformable balls, each ball located in a corresponding ball-receiving concavity and projecting from the interior region of the corresponding ball-receiving concavity through the opening and into the container cavity such that the balls are deformed to accommodate the optical instrument in the container cavity.

Typically, an optical instrument is transported (e.g. shipped or otherwise moved from location to location) by housing the optical instrument in a box or container lined with conventional packaging material such as foam, EPE foam, packing paper, bubble wrap or the like. During transport of the instrument, the box may experience shocks, which may cause associated shock forces to be transmitted through the box and to the optical instrument. Further, the optical instrument may move inside the box, collide with the sidewalls of the box and experience associated collision forces. Such shock forces and/or collision forces may be harmful to the optical instrument.
Different techniques have been used to reduce the forces experienced by optical instruments during transport inside such boxes. For example, the box may be filled with "peanut foam" which may reduce movement of the optical instrument inside the box and reduce the forces transmitted to the optical instrument. However, peanut foam may settle or otherwise move around inside the box during transport, leaving parts of the optical instrument unprotected.
There remains a general desire for more effective ways to house and transport optical instruments while mitigating damage to the optical instruments.

Container for housing optical instruments

Suzhou Synta Optical Technology Co., Ltd.


A method for preventing counterfeiting or theft of sales, bank checks and other important records and documents comprising alphanumeric characters including, the steps of printing different parts of at least come of the characters in a predetermined sequence of colors, dyes or other materials from a printing ribbon on which the segments or color are serially or alternatively deposited in a predetermined sequence of segments. Additionally, the method and apparatus for fabricating a multi-colored printing ribbon by depositing spaced segments of a first color at a first color depositing station and then inserting segments of a second color between said segments of said first color at a second color depositing station. By providing multiple color applying regions at each station carefully controlled color segments are produced on the printing ribbon. Means are provided to adjust segment spacing, the amount of coloring material deposited and the timing of the overall device. Additionally, the ribbon made by the method and apparatus above described.

1. Field of the Invention
This invention relates generally to a method for preventing counterfeiting of sales slips, bank checks and other valuable and sensitive records and documents and more particularly to the apparatus for fabricating multi-colored printing ribbons suitable for use in business machines, printers and for retrofitting existing business machines for printing such records and documents in which the printing ribbon has segments of colors placed serially in an alternating and predetermined sequence along the longitudinal length of the printing ribbon transverse to the entire width of the web of the printing ribbons which are adapted for use in the said method for preventing counterfeiting and that of such records and documents.
2. Description of the Prior Art
It is well-known in the prior art that there are apparatus and methods for fabricating multi-colored printing ribbons having continuous lengths of at least two or more colored inks disposed side-by-side and parallel to each other along the entire length of the longitudinal axis of the web of the multi-colored printing ribbon. In the typical black-red two-colored printing ribbon, a length of black ink and a length of red ink deposited on the web of the printing ribbon each occupy approximately one-half of the entire longitudinal length of the web of the printing ribbon. In the use of such two-colored printing ribbons in any given business machine, the user can establish printed characters from such two-colored printing ribbons in black, in red or some combination of both.
U.S. Pat. No. 3,858,705 to Reitano shows a color-coded digit identifying ribbon for document fraud prevention in which the printing ribbon has parallel sections of colored inks extending along the longitudinal length of the ribbon in a ratio to each other to cover the entire width of the given printing ribbon. Conventionally, this printing ribbon is advanced in the direction of its longitudinal length and the impact business machine or other printers using such multi-color printing ribbon strike it transverse to the longitudinal direction of the movement of the printing ribbon. As a result, each column of characters or numbers can be in the same or in a different color and by comparing the printed color with the assigned color for that column, simple inspection of a record printed with such given ribbon, can tell whether the character or number is correct or has been altered. Because any error in the positioning of each character or the distortion of the color of the ribbon could create a possible error situation, it is essential that the depositing of each section or strip of colored ink on the ribbons being fabricated be very accurate and that no bleeding occur between adjacent colors.
U.S. Pat. No. 4,957,312 describes the existing need for controlling the counterfeiting of sales, bank checks and other valuable records and documents to prevent the use of such printed records for various fraudulent schemes to cheat retailers. Further, that while sophisticated printing equipment or specialized types of papers for such records or documents provides means and methods for overcoming this problem, the costs of such equipment to replace conventional printing equipment and the problems of obtaining cooperation with the suppliers of such specialized papers and the security entailed in preventing any theft of such specialized types of paper or unauthorized distribution of such paper presents additional problems which negative use of either of these solutions to the problem particularly by retailers who operate on low margins of profit.
Since most conventional business machines for producing such sales, bank check and other valuable records rely on impact printing in which a character is formed on a paper substrate as a result of the impact of the printing head upon an intermediate printing ribbon for transferring the impression, shape or alphanumeric characters on the printing head to the substrate paper, U.S. Pat. No. 4,957,312 describes a method of using a multi-colored printing ribbon which fits such conventional business machines or for retrofitting to existing business machines in the commercial marketplace to provide a cheap and easy technique adapted for overcoming this counterfeiting problem.
Thus U.S. Pat. No. 4,957,312 discloses the use of a multi-colored printing ribbon formed with two or more generally parallel lengths of longitudinally extending inked colors deposited along the longitudinally axis of the web of the printing ribbon and in the direction of travel of the ribbon to prevent counterfeiting of sales, bank checks and other important records in which the alphanumeric characters printed with such multi-colored printing ribbon will have at least an upper portion printed in one color while the lower portion is printed in a second color. If more than two colors are used, the central portion of the printed alphanumeric character may be in at least one additional color.
However, depending upon the colors and the coloring materials chosen for inking the printing ribbons made, for example, in accordance with U.S. Pat. No. 4,957,312, the resulting printed characters may be difficult to read or the colors when printed can run into each other which obscures the printed characters when such printing ribbons are used.
The present invention also overcomes the general counterfeiting problems in the commercial marketplace and the difficulties noted above with respect to prior art multi-colored printing ribbons for use with conventional business machines or printers by the method of equipping or retrofitting such business machines or printers with a multi-colored printing ribbon using serially disposed colored ink segments wherein the colored ink segments are arranged alternatively and in predetermined sequence transverse to the width of the longitudinal axis of the given printing ribbon. The alphanumeric characters on the printing head for printing with such improved multi-colored printing ribbons are arranged to strike the interposed intermediate printing ribbon so that the characters are generally in one of the colors of the segments and characters which are struck at the boundaries of a two adjacent colored ink segments may be made of two colors, one on the upper portion, another on the lower portion or with the left portion in one color and the right portion in another. By controlling the length of the colored ink segments deposited on the web of the printing ribbon and limiting the printing field all multi-colored characters may be eliminated or can be established at predetermined points along the line of printing formed by the business machine or printer.

Method for preventing counterfeiting of sales and other records


A recording medium supplied from any one of paper supply units is printed by an image forming section, and then, the image-formed recording medium is transported via a transport path which is formed along a vertical direction, and thereafter is ejected to an ejection unit which is provided at an upper portion of an image forming apparatus main body. While a developing apparatus of a process cartridge owns a developer storage space, a latent image writing position “P” of an image carrier optically written by an optical writing apparatus is located lower than at least a portion of this developer storage space, and a space defined between the paper supply unit 18a and the optical writing apparatus is made small.

1. Field of Invention
The present invention is related to an electro-photographic type image forming apparatus.
2. Description of Related Art
As this sort of image forming apparatus, such an image forming apparatus is known in which while a recording medium is transported along a substantially vertical direction, an image is formed on this transported recording medium, and then, the recording medium on which the image has been formed is ejected to an ejection unit provided on an upper portion of a main body of this image forming apparatus as disclosed in JP-A-10-207160.
The above-described prior art is represented in FIG. 6. In this prior art, a recording medium which has been transported from a paper supply unit 200 by a transport roller 202 is traveled through a transport path 204 which is formed along a substantially vertical direction, and an image is formed on this recording medium by an image forming section 206, and then, this recording medium on which the image has been formed is ejected to an ejection unit 210 which is formed at an upper portion of a main body 208 of the image forming apparatus. The image forming section 206 contains an image carrier 212 constructed of a photosensitive member, a charging apparatus 214 for charging this image carrier 212, an optical writing apparatus 216, a developing apparatus 218, a transferring apparatus 200, a cleaning apparatus 222, and also a fixing apparatus 224. The charging apparatus 214 charges this image carrier 212. The optical writing apparatus 216 forms a latent image on the image carrier 214 charged by this charging apparatus 214. The developing apparatus 218 develops the latent image of the image carrier 214 formed by this optical writing apparatus 216 so as to produce a visible toner image. The transferring apparatus 218 transfers the toner image of the image carrier 214 developed by this developing apparatus 218 onto the recording medium. The cleaning apparatus 222 is constituted by a blade for cleaning developer left on the image carrier 214. The fixing apparatus 224 fixes the toner image which has been transferred onto the recording medium.
The optical writing apparatus 216 is constituted by a scanning type laser exposing apparatus, and is arranged on the side of the developing apparatus 218. In this prior art, when reliability is taken into account, it is preferable to arrange the optical writing apparatus 216 along a horizontal direction. However, since this optical writing apparatus 216 is arranged along an oblique direction, such a device capable of reducing a width of this optical writing apparatus 216 along forward/backward directions (namely, right/left directions as viewed in FIG. 6) can be made.
However, in such a type of image forming apparatus that the recording medium is transported along the substantially vertical direction, dead spaces 226 and 228 are formed at both upper/lower portions of the optical writing apparatus 216 within the ejection unit 210 provided at the upper portion of this image forming apparatus. In other words, since the developing apparatus 218 is arranged at a position lower than a latent image writing position "P" where the latent image is written onto the image carrier 212 by the optical writing apparatus 216, the optical writing apparatus 216 must be arranged above the developing apparatus 218. As a result, the dead space 226 is formed between the ejection unit 210 and the optical writing apparatus 216, and also, the dead space 228 is formed between the optical writing apparatus 216 and the paper supply unit 200.
Moreover, conventionally, an image is transferred onto the image carrying body, while transporting the recording sheet in the substantially vertical direction, and scanning light is laterally incident on the image carrying body.
In this case, a toner replenishment box is disposed in downstream (in a lower part in this instance) of a latent image writing position on the image carrying body. Accordingly, the toner replenishment box does not hinder the operation of writing the latent image onto the image carrying body.
However, in this type of technique, the toner replenishment box is disposed in downstream (in a lower part in this instance) of a scanning light incident position. Therefore, for example, when the amount of toner is increased, the toner amount increase more easily affects the positions of a sheet tray and the optical unit, which are disposed in the lower part, since the volume of the toner replenishment box is increased. Changes to the specification of the machine, caused by the toner replenishing amount change, are not uniform. This makes it difficult to use the image forming apparatus in common for different specifications. An additional problem is that with increase of the toner replenishing amount, the machine size tends to increase.
Further, in a case where the machine is designed so as to allow the toner replenishment box to be pulled out from an upper part of the machine body, it entails that it is difficult to install another device in an upper space of the toner replenishment box. An additional technical problem arises that a dead space is easy to be formed in upstream (in an upper part in this instance) of the scanning light incident position.
Particularly in a case where the process cartridge is equipped with the toner replenishment box, such a technical problem is more remarkable by the amount of its occupied space increase.

Image forming apparatus and developer replenishment portion


An angular rate sensor includes a quadratic prism-like oscillator 1a formed by laminating a substrate 2 and a piezoelectric material 3, the piezoelectric material 3 is made of piezoelectric ceramics including PZT (Lead Zirconate Titanate) as a main component, and the substrate 2 is made of a material other than PZT having physical property values equivalent to or less than PZT, which is a main component of the piezoelectric ceramics, with respect to Young's modulus, thermal expansion coefficient, and the like.

1. Field of the Invention
The present invention relates to an angular rate sensor used for detecting e.g., video camera shake, the operation of a virtual reality apparatus, the direction in a car navigation system or the like.
2. Description of the Related Art
A so-called oscillation gyro type angular rate sensor has been widely available as consumer use. The osillation gyro type angular rate sensor detects angular rate by oscillating a rod-like oscillator at a predetermined resonance frequency and detecting Coriolis force generated by influence of angular rate with a piezoelectric element or the like.
For driving an oscillator in the angular rate sensor like this, a method using a separately-excited oscillation type driving circuit and one using a self-excited oscillation type driving circuit are available. However, the method using a separately-excited oscillation type driving circuit has a problem that when a difference is made between oscillation frequency and resonance frequency of an oscillator due to influence of temperature characteristics of the oscillator or the like, sensitivity for detecting Coriolis force rapidly decreases. Therefore, the method using a separately-excited oscillation type driving circuit has not been in practical use.
Consequently, the method using a self-excited oscillation type driving circuit in which the oscillator is incorporated in a loop of a phase-shift oscillator circuit is now widely used. Since the angular rate sensor using this method self-oscillates at the resonance frequency of oscillator, sensitivity thereof hardly changes due to influence of the temperature characteristics, thereby obtaining an angular rate output having stable sensitivity in a wide temperature range (refer, for example, to Jpn. Pat. Appln. Laid-Open Publication No. 2000-131077).
A conventional angular rate sensor shown in FIGS. 1A, 1B, and 1C includes a triangular prism-like oscillator 104 having a triangular prism-like constant elastic oscillator 100. The constant elastic oscillator 100 has first to third piezoelectric elements 101 to 103 attached to the side surfaces thereof, respectively. The first piezoelectric element 101 is composed of an electrode 101a and a piezoelectric material 101b. The second piezoelectric element 102 is composed of an electrode 102a and a piezoelectric material 102b. The third piezoelectric element 103 is composed of an electrode 103a and a piezoelectric material 103b. For example, the constant elastic oscillator 100 is a constant elastic metal oscillator.
The conventional angular rate sensor includes an amplifier 105 connected to the first piezoelectric element 101, a phase shifter 106 connected to the amplifier 105, a differential amplifier 107 connected to the second and third piezoelectric elements 102 and 103, a synchronous detector 108 connected to the differential amplifier 107, and a low-pass filter 109 connected to the synchronous detector 108. In the conventional angular rate sensor, the second and third piezoelectric elements 102 and 103 detect oscillation of the oscillator 104 for performing self-excited oscillation as well as Coriolis force generated in the oscillator 104.
The angular rate sensor using the triangular prism-like oscillator 104 has the highest sensitivity at the present time and therefore is currently mainstream. However, the angular rate sensor of this type has a complicated structure, which makes it difficult to produce high volume efficiency in manufacturing process. For example, in the above configuration, process of bonding piezoelectric elements to each of the triangular prism-like constant elastic oscillators is required, with the result that volume efficiency cannot be improved. Further, along with the miniaturization of the sensor, accuracy in a support mechanism or bonding accuracy of the piezoelectric element to the constant elastic metal oscillator has been increasingly demanded. In addition, influence of a bonding layer to the oscillator is increased. Therefore, manufacturing efficiency is lowered and manufacturing cost is significantly increased.
Another conventional angular rate sensor shown in FIGS. 2A, 2B and 2C includes an oscillator 117 having a columnar piezoelectric ceramic oscillator 110. The piezoelectric ceramic oscillator 110 has six electrodes 111 to 116 printed on a side surface thereof. The first to third electrodes 111 to 113 are independently formed. The fourth to sixth electrodes 114 to 116 are connected to the same ground potential. This angular rate sensor includes an amplifier 118 connected to the first electrode 111, a phase shifter 119 connected to the amplifier 118, an adder 120 connected to the phase shifter 119, a differential amplifier 121 connected to the second and third electrodes 112 and 113, a synchronous detector 122 connected to the differential amplifier 121, and a low-pass filter 123 connected to the synchronous detector 122. This angular rate sensor applies a voltage to the first electrode 111 to oscillate the oscillator 117, and detects Coriolis force generated in the oscillator 117 with the second and third electrodes 112 and 113.
In this conventional angular rate sensor, the electrodes 111 to 116 are printed on the oscillator 117 as described above. This eliminates the need to bond the piezoelectric elements to the oscillator 117 and makes the structure of the sensor relatively simple. However, in the case where the sensor size is reduced, it is difficult to produce an accurately configured piezoelectric ceramic oscillator 110 and, it is also difficult to print the electrodes onto the piezoelectric ceramic oscillator 110 with high accuracy.
That is, while this conventional angular rate sensor uses the columnar piezoelectric ceramic oscillator 110, it is difficult to manufacture, with high accuracy, the columnar piezoelectric ceramic oscillator 110 as compared to the triangular prism-like or quadratic prism-like oscillator. Further, it is not easy to print the electrodes onto the rounded surface of this angular rate sensor with high accuracy. As described above, the use of the columnar piezoelectric ceramic oscillator 110 makes it difficult to produce the angular rate sensor in large volume. Even though the mass-production has been realized, it is difficult to reduce manufacturing cost.
In addition to the conventional oscillation configuration of the angular rate sensor, unimorph-type and bimorph-type oscillators are widely used.
In the unimorph-type and bimorph-type oscillators, a combination of the same materials such as PZT (Lead Zirconate Titanate) are used to form the oscillator in general, in order to reduce manufacturing cost by common use of raw materials, to stabilize workability, to increase accuracy, and to reduce adversely effect due to influence of adhesion performance or thermal characteristics change.
However, since the thermal characteristics change in a piezoelectric material, such as PZT or the like, is non-linear, it is difficult to reduce temperature change in some characteristics in the case where the PZT is used as a substrate. Further, when detection sensitivity or detuning degree (frequency difference between lateral and vertical oscillations) that greatly contributes the detection sensitivity or frequency responsibility needs to be freely designed, the above factors are uniquely determined by section size of the oscillator and materials of the substrate, with the result that design freedom of a configuration of the oscillator tends to be limited.
Further, in the case of non-polarized state (mono-morph) in which the same PZTs are laminated and thereby the substrate does not have piezoelectricity, characteristics change in the resonance resistance obtained in the case where a single body of the oscillator is self-oscillated or in the sensitivity of an angular rate sensor using the same oscillator with respect to environmental temperature is large. This characteristics change tends to increase with higher temperatures. Thus, it is necessary to compensate the characteristics change by means of an electric circuit in order to maintain a predetermined performance level even at the place where environmental temperature change is large, such as outdoors, which makes it very difficult to simplify a circuit configuration and to reduce the number of parts. Further, it is difficult to fully compensate the above characteristics change using the electrical circuit since the characteristics change itself is non-linear. Therefore, the angular rate sensor using the same oscillator cannot be applied to the model having narrow tolerance ranges in characteristics change with respect to environmental change.
In the angular rate sensor for stabilizing an image, which is often mounted in devices provided with an image output unit, such as a video camera, it is necessary to control oscillation frequency of the oscillator to fall within a predetermined range in order to prevent interference of electromagnetic wave traveling in the case of the device, vibration or the like, or mutual interaction between them. Further, in order to allow detuning degree, which shows a strong correlation with sensitivity or frequency responsibility, to have a target value, vertical oscillation frequency and lateral oscillation frequency must be separately adjusted. However, when an initial state value is very far from the target value, not only it becomes difficult to perform adjustment itself, but there is a possibility that the adjustment cannot be achieved.
Note that the detuning degree is a difference between resonance frequencies in the vertical and lateral directions. The smaller the detuning degree, the higher the sensitivity becomes.


A memory cell and structure are implemented to provide a memory system having the advantages of both static and dynamic memories. A dynamic memory cell is implemented using a capacitor to store charge associated with a data value stored in the cell. The storage capacitor is accessible through multiple switches, and each of the switches is coupled to an independent bitline. Because independent bitlines are implemented, one bitline may sense the data value stored within the memory cell, while a second bitline is pre-charged, or refreshed, for a next memory operation to be performed. Thus, as soon as data is provided to the first bitline, any memory cells sharing the second bitline are ready to be sensed and restored even though they are all in the same data memory array. Such sequential operation is not possible with prior art DRAM memory cells because they require a refresh period in which to pre-charge bitlines accessing the same memory location. By providing the ability to access the same memory cell during a next subsequent timing cycle, a DRAM cell having a very low latency is implemented.

As semiconductor technology has advanced, data processing applications, such as personal computers, workstations, communication systems, and the like have evolved rapidly to require faster and larger memory storage spaces. Specifically, semiconductor data processing systems typically implement RAM memories that allow any part of a memory to be read or written as fast as any part. Semiconductor RAMs are generally classified as non-volatile, static, and dynamic. Non-volatile RAMs are typically used for information that should be permanently stored, such as system information that is accessed during system start-up. A static RAM stores data in latches and is able to retain information while power is supplied to the memory. When the power is removed from the memory, the static memory loses all data stored therein. A dynamic random access memory (DRAM) is implemented through the use of a substantially smaller memory cell that must be refreshed periodically. Without such refresh operations, the DRAM cell would lose its information due to cell leakage through a capacitor implemented therein.
While DRAMs provide compact memory cells, the refresh requirements of DRAMs, in combination with other circuit requirements for proper operation, result in slower memory access times. Over the last two decades, the internal speed of data processors including microcontrollers and microprocessors has improved by a factor of approximately forty, while DRAM speed has improved by a factor of less than two. Furthermore, microprocessor clock frequencies are anticipated to quickly reach the 1 GHz range, while the fastest DRAM is only expected to reach 200 MHz in the same time period.
The speed of DRAMs is limited by several factors. For example, DRAMs tend to have longer cycle times because they are optimized for low power and not for speed, compared to static RAMs and some random logic circuits. Specifically, the speed with which a DRAM cell operates is limited by the requirement that the cell be periodically refreshed to compensate for the leakage of a capacitor used to implement each cell. In addition to the refreshing requirement, cycle times may also be adversely affected by contention from the refreshing requirement. Contention occurs when a DRAM memory cell that is being refreshed is concurrently required for access. In addition, read and write operations require a "pre-charge" or set up time, prior to "data sense and amplification.". Such information is well-known in the industry and is explained in greater detail in "Session XVII: Random Access Memories," by L. White, et al., published in the proceedings of the 1980 IEEE International Solid State Circuit Conference. Typically, the refresh operation has priority over other operations in DRAMs. Therefore, the read or write operation is postponed at least until the refresh operation is performed. In an effort to relieve such contention, some memory systems include cache memories, wherein a central processing unit of a data processing system is able to access a limited amount of memory more quickly and without potential contention problems, as such cache memory is typically implemented as a static RAM. However, even with the implementation of cache memories, cache misses occur when the required data is not available in the static RAM. Therefore, the data must then be accessed from the DRAM in a more time consuming operation.
In addition to the limitations associated with refresh operations and potential contention, DRAMs also have latency problems. Latency is a parameter used to measure an amount of time required to access a number of DRAM cells, a byte, or word after the appropriate address is asserted. Thus, the latency associated with a typical 16 megabit bank of DRAM cells that has 4,096 rows and 4,096 columns will be measured as a time required to step through such row or column of the memory, defined by the above-mentioned asserted address.
In an effort to solve some of the issues associated with refreshing, contention, and latency, several DRAM configuration and operation techniques have been implemented. Most recently, the use of a synchronous DRAM has been implemented to improve the speed associated with the conventional DRAM cell and memory peripheral circuits. Such synchronous DRAMs implement a 3-stage pipelined architecture to access conventional DRAM cells in a more timely manner. For additional information on such synchronous DRAM architectures, refer to "250MByte/Synchronous DRAM Using a 3-Stage Pipelined Architecture," IEEE Journal of Solid-State Circuits, Volume 29, No. 4, April 1994, by Yasuhiro Takai, et al., pp. 426-430. However, while methodologies, including synchronous DRAMs, have been implemented to optimize the latency, contention, and refresh requirements of DRAM cells, a requirement that a DRAM cell be refreshed still remains. This requirement imposes timing constraints that cannot be overcome using traditional memory cell implementations. Therefore, a need exists for a new memory cell, system architecture, and method for using both to meet the ever increasing demands for faster processing and greater memory capacity. Such implementation should be comprehensive and cost effective, as well as reduce the latency typically associated with the refresh requirements and resulting contention in a DRAM memory system.

Low latency DRAM cell and method therefor