7400 the 7400 chip containing four nands the sn prefix indicates this chip was manufactured by texas instruments surfacemount 74hc595 shift registers on a pcb this 74hc variant of the 74595 uses cmos signalling voltage levels while the 74hct595 variant uses ttl signalling levels the 7400 series of transistortransistor logic ttl integrated circuits are the most popular family of ttl integrated circuit logic quickly replacing diodetransistor logic it was used to build the mini and mainframe computers of the 1960s and 1970s several generations of pincompatible descendants of the original family have since become de facto standard electronic components overview the 7400 series contains hundreds of devices that provide everything from basic logic gates flipflops and counters to special purpose bus transceivers and arithmetic logic units alu specific functions are described in a list of 7400 series integrated circuits some ttl logic parts were made with an extended militaryspecification temperature range these parts are prefixed with 54 instead of 74 in the part number a shortlived 64 prefix on texas instruments parts indicated an industrial temperature range this prefix had been dropped from the ti literature by 1973 since the 1970s new product families have been released to replace the original 7400 series more recent ttl logic families are developed cmos or bicmos technology rather than ttl today surfacemounted cmos versions of the 7400 series are used in various applications in electronics and for glue logic in computers and industrial electronics the original throughhole devices in dual inline packages dipdil were the mainstay of the industry for many decades they are useful for rapid breadboardprototyping and for education and remain available from most manufacturers the fastest types and very low voltage versions are typically surfacemount only however the first part number in the series the 7400 is a 14pin ic containing four twoinput nand gates each gate uses two input pins and one output pin with the remaining two pins being power 5 v and ground this part was made in various throughhole and surfacemount packages including flat pack and plasticceramic dual inline additional characters in a part number identify the package and other variations while designed as a family of digital logic some ttl chips were used in analogue circuits such as schmitt triggers history although the 7400 series was the first de facto industry standard ttl logic family ie secondsourced by several semiconductor companies there were earlier ttl logic families such as sylvania universal highlevel logic in 1963 motorola mc4000 mttl national semiconductor dm8000 fairchild 9300 series signetics 8200 and 8t00 the 7400 quad nand gate was the first product in the series introduced by texas instruments in a military grade metal flat package 7400w in october 1964 the extremely popular commercial grade plastic dip 7400n followed in the third quarter of 1966 the 5400 and 7400 series were used in many popular minicomputers in the 1970s and early 1980s some models of the dec pdpseries minis used the 74181 alu as the main computing element in the cpu other examples were the data general nova series and hewlettpackard 21mx 1000 and 3000 series hobbyists and students equipped with wire wrap tools a breadboard and a 5volt power supply could also experiment with digital logic referring to howto articles in byte magazine and popular electronics which featured circuit examples in nearly every issue in the early days of largescale ic development a prototype of a new largescale integrated circuit might have been developed using ttl chips on several circuit boards before committing to manufacture of the target device in ic form this allowed simulation of the finished product and testing of the logic before the availability of software simulations of integrated circuits in 1965 typical quantityone pricing for the sn5400 military grade in ceramic welded flatpack was around 22 usd as of 2007 individual commercialgrade chips in molded epoxy plastic packages can be purchased for approximately 025 usd each depending on the particular chip families part of the 7400 series cascadable 8bit alu texas instruments sn74as888 die of a 74hc595 8bit shift register die of a 74ahc00d quad 2input nand gate manufactured by nxp semiconductors 7400 series parts were constructed using bipolar transistors forming what is referred to as transistortransistor logic or ttl newer series more or less compatible in function and logic level with the original parts use cmos technology or a combination of the two bicmos originally the bipolar circuits provided higher speed but consumed more power than the competing 4000 series of cmos devices bipolar devices are also limited to a fixed power supply voltage typically 5v while cmos parts often support a range of supply voltages milspecrated devices for use in extended temperature conditions are available as the 5400 series texas instruments also manufactured radiationhardened devices with the prefix rsn and the company offered beamlead bare dies for integration into hybrid circuits with a bl prefix designation regularspeed ttl parts were also available for a time in the 6400 series these had an extended industrial temperature range of 40c to 85c while companies such as mullard listed 6400series compatible parts in 1970 data sheets by 1973 there was no mention of the 6400 family in the texas instruments ttl data book some companies have also offered industrial extended temperature range variants using the regular 7400series part numbers with a prefix or suffix to indicate the temperature grade as integrated circuits in the 7400 series were made in different technologies usually compatibility was retained with the original ttl logic levels and power supply voltages an integrated circuit made in cmos is not a ttl chip since it uses fieldeffect transistors fets and not bipolar junction transistors but similar part numbers are retained to identify similar logic functions and electrical power and io voltage compatibility in the different subfamilies over 40 different logic subfamilies use this standardized part number scheme bipolar 74 standard ttl the original logic family had no letters between the 74 and the part number 10 ns gate delay 10mw dissipation 475525 v released in 1966 74l lowpower larger resistors allowed 1mw dissipation at the cost of a very slow 33 ns gate delay obsolete replaced by 74ls or cmos technology introduced 1971 74h highspeed 6 ns gate delay but 22mw power dissipation used in 1970s era supercomputers still produced but generally superseded by the 74s series introduced in 1971 74s highspeed schottky implemented with schottky diode clamps at the inputs to prevent charge storage this provides faster operation than the 74 and 74h series at the cost of increased power consumption and cost 3 ns gate delay 20mw dissipation released in 1971 74ls lowpower schottky implemented using the same technology as 74s but with reduced power consumption and switching speed typical 10 ns gate delay a remarkable for the time 2mw dissipation 475525 v 74as advanced schottky the next iteration of the 74s series with greater speed and fanout despite lower power consumption implemented using the 74ss technology with miller killer circuitry to speed up the lowtohigh transition 17 ns gate delay 8mw 4555 v 74als advanced lowpower schottky same technology as 74as but with the speedpower tradeoff of the 74ls 4 ns 12mw 4555 v 74f fast fairchilds version of tis 74as 34 ns 6mw 4555 v introduced in 1978 cmos c cmos 415 v operation similar to buffered 4000 4000b series hc highspeed cmos similar performance to 74ls 12 ns 2060 v hct high speed compatible logic levels to bipolar parts ac advanced cmos performance generally between 74s and 74f act advanced cmos performance generally between 74s and 74f compatible logic levels to bipolar parts acq advanced cmos with quiet outputs ahc advanced highspeed cmos three times as fast as 74hc tolerant of 55v on input alvc lowvoltage 1833 v time propagation delay tpd 3 ns at 33 v alvt lowvoltage 2533 v 5 v tolerant inputs high current 64 ma tpd 3 ns at 25 v auc lowvoltage 0825 v tpd 25 ns at 18 v aup lowvoltage 0836 v 33 v typically tpd 1568243 ns at 121833v partial powerdown specified ioff inputs protected avc lowvoltage 1233 v tpd 32 ns at 18 v bus hold ioff axc lowvoltage 06536 v tpd 32 ns at 18 v bus hold ioff fc fast cmos performance similar to 74f lcx cmos with 3 v supply and 5 v tolerant inputs lv lowvoltage cmos 2055 v supply and 5 v tolerant inputs lvc low voltage 16533 v and 5 v tolerant inputs tpd 55 ns at 33 v tpd 9 ns at 25 v lva 255 v 5 v tolerant inputs tpd 10 ns at 33 v bus hold ioff low noise lvt lowvoltage 33 v supply 5 v tolerant inputs high output current 64 ma tpd 35 ns at 33 v ioff low noise lvq lowvoltage 33 v lvx lowvoltage 33 v with 5 v tolerant inputs vhc veryhighspeed cmos 74s performance in cmos technology and power bicmos bct bicmos ttlcompatible input thresholds used for buffers abt advanced bicmos ttlcompatible input thresholds faster than 74act and 74bct many parts in the cmos hc ac and fc families are also offered in t versions hct act and fct which have input thresholds that are compatible with both ttl and 33v cmos signals the nont parts have conventional cmos input thresholds the 74h family is the same basic design as the 7400 family with resistor values reduced this reduced the typical propagation delay from 9ns to 6ns but increased the power consumption the 74h family provided a number of unique devices for cpu designs in the 1970s many designers of military and aerospace equipment used this family over a long period and as they need exact replacements this family is still produced by lansdale semiconductor the 74s family using schottky circuitry uses more power than the 74 but is faster the 74ls family of ics is a lowerpower version of the 74s family with slightly higher speed but lower power dissipation than the original 74 family it became the most popular variant once it was widely available the 74f family was introduced by fairchild semiconductor and adopted by other manufacturers it is faster than the 74 74ls and 74s families through the late 1980s and 1990s newer versions of this family were introduced to support the lower operating voltages used in newer cpu devices characteristics of selected 7400 series families parameter 74c 74hc 74ac 74hct 74act units vdd 5 v vih min 35 20 v voh min 45 49 v vil max 15 10 15 08 v vol max 05 01 v iih max 1 a iil max 1 a ioh max 04 40 24 40 24 ma iol max 04 40 24 40 24 ma tp max 50 8 47 8 47 ns part numbering a 4bit 2 register sixinstruction computer made entirely of 74series chips see also list of 7400series integrated circuits part number schemes varied by manufacturer the part numbers for 7400series logic devices often use the following designators often first a two or three letter prefix denoting the manufacturer and flow class of the device eg sn for texas instruments using a commercial processing snv for texas instruments using military processing m for st microelectronics dm for national semiconductor ut for cobham plc sg for sylvania these codes are no longer closely associated with a single manufacturer for example fairchild semiconductor manufactures parts with mm and dm prefixes and no prefixes two digits where 74 denotes a commercial temperature range device and 54 denotes a military temperature range historically 64 denoted a shortlived series with an intermediate industrial temperature range no or up to four letters denoting the logic subfamily such as ls hct or nothing for basic bipolar ttl two or more arbitrarily assigned digits that identify the function of the device there are hundreds of different devices in each family additional suffix letters and numbers may be appended to denote the package type quality grade or other information but this varies widely by manufacturer for example sn5400n signifies that the part is a 7400series ic probably manufactured by texas instruments sn originally meaning semiconductor network using commercial processing is of the military temperature rating 54 and is of the ttl family absence of a family designator its function being the quad 2input nand gate 00 implemented in a plastic throughhole dip package n many logic families maintain a consistent use of the device numbers as an aid to designers often a part from a different 74x00 subfamily could be substituted dropin replacement in a circuit with the same function and pinout yet more appropriate characteristics for an application perhaps speed or power consumption which was a large part of the appeal of the 74c00 series over the competing cd4000b series for example but there are a few exceptions where incompatibilities mainly in pinout across the subfamilies occurred such as some flatpack devices eg 7400w and surfacemount devices some of the faster cmos series for example 74ac a few lowpower ttl devices eg 74l86 74l9 and 74l95 have a different pinout than the regular or even 74ls series part five versions of the 74x54 4wide andorinvert gates ic namely 7454n 7454w 74h54 74l54w and 74l54n74ls54 are different from each other in pinout andor function second sources from europe and eastern bloc soviet k131la3 equivalent to 74h00 czechoslovak mh74s00 texas instruments sn74s251n east german dl004d 74ls04 soviet k155la13 7438 polish ucy7473 some manufacturers such as mullard and siemens had pincompatible ttl parts but with a completely different numbering scheme however data sheets identified the 7400compatible number as an aid to recognition at the time the 7400 series was being made some european manufacturers that traditionally followed the pro electron naming convention such as philipsmullard produced a series of ttl integrated circuits with part names beginning fj some examples of fj series are fjh101 7430 single 8input nand gate fjh131 7400 quadruple 2input nand gate fjh181 7454n or j 2222 input andornot gate the soviet union started manufacturing ttl ics with 7400series pinout in the late 1960s and early 1970s such as the k155a3 which was pincompatible with the 7400 part available in the united states except for using a metric spacing of 25mm between pins instead of the 01 inches 254mm pintopin spacing used in the west another peculiarity of the sovietmade 7400 series was the packaging material used in the 1970s1980s instead of the ubiquitous black resin they had a brownishgreen body colour with subtle swirl marks created during the moulding process it was jokingly referred to in the eastern bloc electronics industry as the elephantdung packaging due to its appearance the soviet integrated circuit designation is different from the western series the technology modifications were considered different series and were identified by different numbered prefixes 155 series is equivalent to plain 74 555 series is 74ls etc the function of the unit is described with a twoletter code followed by a number the first letter represents the functional group logical triggers counters multiplexers etc the second letter shows the functional subgroup making the distinction between logical nand and nor d and jktriggers decimal and binary counters etc the number distinguishes variants with different number of inputs or different number of elements within a die 123 la1la2la3 are 2 fourinput 1 eightinput 4 twoinput nand elements respectively equivalent to 742074307400 before july 1974 the two letters from the functional description were inserted after the first digit of the series examples 1551 and 1551 7420 1552 and 1552 7474 are the same ics made at different times clones of the 7400 series were also made in other eastern bloc countries bulgaria mikroelektronika botevgrad used a designation somewhat similar to that of the soviet union eg 100 1lb00shm for a 74ls00 some of the twoletter functional groups were borrowed from the soviet designation while others differed unlike the soviet scheme the two or three digit number after the functional group matched the western counterpart the series followed at the end ie for ls only the ls series is known to have been manufactured in bulgariapp811 czechoslovakia tesla used the 7400 numbering scheme with manufacturer prefix mh example mh7400 poland unitra cemi used the 7400 numbering scheme with manufacturer prefixes uca for the 5400 and 6400 series as well as ucy for the 7400 series examples uca6400 ucy7400 note that ics with the prefix mcy74 correspond to the 4000 series eg mcy74002 corresponds to 4002 and not to 7402 hungary tungsram later mikroelektronikai vllalat mev also used the 7400 numbering scheme but with manufacturer suffix 7400 is marked as 7400apc romania used trimmed 7400 numbering with own manufacturing prefix cdb example cdb4123e is 74123 east germany hfo also used trimmed 7400 numbering without manufacturer prefix or suffix the prefix d or e designates digital ic and not the manufacturer example d174 is 7474 74ls clones were designated by the prefix dl eg dl000 74ls00 in later years east german made clones were also available with standard 74 numbers usually for export a number of different technologies were available from the soviet union czechoslovakia poland the 8400 series in the table below indicates an industrial temperature range from 25c to 85c as opposed to 40c to 85c for the 6400 series prefixes of eastern european series soviet union czechoslovakia poland east germany 5400 7400 5400 7400 8400 5400 6400 7400 7400 8400 74 133 155 mh54 mh74 mh84 uca54 uca64 ucy74 d1 e1 74l 134 134 74h 130 131 uca64h ucy74h d2 e2 74s 530 531 mh54s mh74s mh84s ucy74s ds 74ls 533 555 ucy74ls dl 74as 1530 1530 74als 1533 1533 mh54als mh74als 74f 1531 1531 74hc 1564 1564 74hct u74hct 74ac 1554 1554 74act 1594 1594 74lvc 5574 74vhc 5584 around 1990 the production of standard logic ceased in all eastern european countries except the soviet union and later russia and belarus as of 2016 the series 133 155 1533 1533 1554 1594 and 5584 were in production at integral in belarus as well as the series 130 and 530 at nzppkbr 134 and 5574 at vzpp 533 at svetlana 1564 1564 1564 at nzpp 1564 1564 at voshod and 1564 at exiton in russia the russian company angstrem manufactures 54hc circuits as the 55141 series 54ac as the 55142 series and 54lvc as the 55242 series 4000series integrated circuits list of 4000series integrated circuits pushpull output opencollectordrain output threestate output schmitt trigger input logic gate logic family programmable logic device pin compatibility book ttl cookbook don lancaster sams publishing 412 pages 1974 isbn9780672210358 designing with ttl integrated circuits robert l morris and john r miller mcgrawhill 322 pages 1971 isbn9780070637450 fairchild semiconductor on semiconductor historical data books ttl 1978 752 pages fast 1981 349 pages logic selection guide 2008 12 pages nxp semiconductor nexperia logic selection guide 2017 176 pages texas instruments national semiconductor historical catalog 1967 375 pages historical databooks ttl vol1 1984 339 pages ttl vol2 1985 1402 pages ttl vol3 1984 793 pages ttl vol4 1986 445 pages digital logic pocket data book 2007 794 pages logic reference guide 2004 8 pages logic selection guide 1998 215 pages little logic guide 2018 25 pages little logic selection guide 2004 24 pages wikimedia commons has media related to 7400 series understanding 7400series digital logic ics nuts and volts magazine thorough list of 7400series ics electronics club 