The following is a list of 7400-series digital logic integrated circuits. In the mid-1960s, the original 7400-series integrated circuits were introduced by Texas Instruments with the prefix "SN" to create the name SN74xx. Due to the popularity of these parts, other manufacturers released pin-to-pin compatible logic devices and kept the 7400 sequence number as an aid to identification of compatible parts. However, other manufacturers use different prefixes and suffixes on their part numbers. Overview Some TTL logic parts were made with an extended military-specification temperature range. These parts are prefixed with 54 instead of 74 in the part number. A short-lived 64 prefix on Texas Instruments parts indicated an industrial temperature range; this prefix had been dropped from the TI literature by 1973. Most recent 7400-series parts are fabricated in CMOS or BiCMOS technology rather than TTL. Surface-mount parts with a single gate (often in a 5-pin or 6-pin package) are prefixed with 741G instead of 74. Some manufacturers released some 4000-series equivalent CMOS circuits with a 74 prefix, for example, the 74HC4066 was a replacement for the 4066 with slightly different electrical characteristics (different power-supply voltage ratings, higher frequency capabilities, lower "on" resistances in analog switches, etc.). See List of 4000-series integrated circuits. Conversely, the 4000-series has "borrowed" from the 7400 series such as the CD40193 and CD40161 being pin-for-pin functional replacements for 74C193 and 74C161. Older TTL parts made by manufacturers such as Signetics, Motorola, Mullard and Siemens may have different numeric prefix and numbering series entirely, such as in the European FJ family FJH101 is an 8-input NAND gate like a 7430. A few alphabetic characters to designate a specific logic subfamily may immediately follow the 74 or 54 in the part number, e.g., 74LS74 for low-power Schottky. Some CMOS parts such as 74HCT74 for high-speed CMOS with TTL-compatible input thresholds are functionally similar to the TTL part. Not all functions are available in all families. The generic descriptive feature of these alphabetic characters was diluted by various companies participating in the market at its peak and are not always consistent especially with more recent offerings. The National Semiconductor trademarks of the words FAST and FACT are usually cited in the descriptions from other companies when describing their own unique designations. In a few instances, such as the 7478 and 74107, the same suffix in different families do not have completely equivalent logic functions. Another extension to