7400 series

7400 series

Overview


The 7400 series of transistor-transistor logic
Transistor-transistor logic
Transistor–transistor logic is a class of digital circuits built from bipolar junction transistors and resistors. It is called transistor–transistor logic because both the logic gating function and the amplifying function are performed by transistors .TTL is notable for being a widespread...

 (TTL) integrated circuit
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

s are historically important as the first widespread family
Logic family
In computer engineering, a logic family may refer to one of two related concepts. A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply...

 of TTL integrated circuit logic. It was used to build the mini and mainframe computers of the 1960s and 1970s. Several generations of pin-compatible
Pin-compatibility
In electronics, a pin-compatible device, such as a logic integrated circuit , memory module or microprocessor, is one that has the same functions assigned to the same particular pins....

 descendants of the original family have since become de-facto standard electronic components.

The 7400 series contains hundreds of devices that provide everything from basic logic gates, flip-flop
Flip-flop (electronics)
In electronics, a flip-flop or latch is a circuit that has two stable states and can be used to store state information. The circuit can be made to change state by signals applied to one or more control inputs and will have one or two outputs. It is the basic storage element in sequential logic...

s, and counters, to special purpose bus transceivers and Arithmetic Logic Units (ALU).
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Encyclopedia


The 7400 series of transistor-transistor logic
Transistor-transistor logic
Transistor–transistor logic is a class of digital circuits built from bipolar junction transistors and resistors. It is called transistor–transistor logic because both the logic gating function and the amplifying function are performed by transistors .TTL is notable for being a widespread...

 (TTL) integrated circuit
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

s are historically important as the first widespread family
Logic family
In computer engineering, a logic family may refer to one of two related concepts. A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply...

 of TTL integrated circuit logic. It was used to build the mini and mainframe computers of the 1960s and 1970s. Several generations of pin-compatible
Pin-compatibility
In electronics, a pin-compatible device, such as a logic integrated circuit , memory module or microprocessor, is one that has the same functions assigned to the same particular pins....

 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, flip-flop
Flip-flop (electronics)
In electronics, a flip-flop or latch is a circuit that has two stable states and can be used to store state information. The circuit can be made to change state by signals applied to one or more control inputs and will have one or two outputs. It is the basic storage element in sequential logic...

s, and counters, to special purpose bus transceivers and Arithmetic Logic Units (ALU). Specific functions are described in a list of 7400 series integrated circuits.

Today, surface-mounted CMOS versions of the 7400 series are used in various applications in electronics and for glue logic
Glue logic
In electronics, glue logic is the custom logic circuitry used to interface a number of off-the-shelf integrated circuits.This is often achieved using ordinary 7400- or 4000-series components. In more complex cases, programmable logic devices like a CPLD or FPGA might be used...

 in computers and industrial electronics. The original through-hole devices in dual in-line package
Dual in-line package
In microelectronics, a dual in-line package is an electronic device package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be through-hole mounted to a printed circuit board or inserted in a socket.A DIP is usually referred to as a DIPn, where n is...

s (DIP/DIL), which were the mainstay of the industry for many decades, are very useful for rapid breadboard
Breadboard
A breadboard is a construction base for prototyping of electronics. The term is commonly used to refer to solderless breadboard ....

-prototyping and education and so remain available from most manufacturers. The fastest types and very low voltage versions are typically surface-mount only, however.

The 14-pin DIP is an example of a 7400 part. The chip contains four two-input NAND gate
NAND gate
The Negated AND, NO AND or NAND gate is the opposite of the digital AND gate, and behaves in a manner that corresponds to the opposite of AND gate, as shown in the truth table on the right. A LOW output results only if both the inputs to the gate are HIGH...

s. Each gate uses two pins for input and one pin for its output, and the remaining two contacts supply power (+5 V) and connect the ground.

While designed as a family of digital logic, it was not unusual to see TTL chips in analog circuits like Schmitt triggers. Like the 4000 series
4000 series
The 4000 series is a family of industry standard integrated circuits which implement a variety of logic functions using Complementary Metal–Oxide–Semiconductor technology, and are still in use today. They were introduced by RCA as CD4000 COS/MOS series in 1968, as a lower power and more versatile...

, the newer CMOS
CMOS
Complementary metal–oxide–semiconductor is a technology for constructing integrated circuits. CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits...

 versions of the 7400 series are also usable as analog amplifiers using negative feedback (similar to operational amplifier
Operational amplifier
An operational amplifier is a DC-coupled high-gain electronic voltage amplifier with a differential input and, usually, a single-ended output...

s with only an inverting input).

The former Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 manufactured the K155ЛA3 which was pin-compatible with the 7400 part available in the United States, except for using a metric spacing of 2.5mm between pins instead of the 1/10"-based (2.54mm) spacing used in the west.

7400 series derivative families



7400 series parts were constructed using bipolar transistors, forming what is referred to as transistor–transistor logic or TTL. Newer series, more or less compatible in function and logic level with the original parts, use CMOS
CMOS
Complementary metal–oxide–semiconductor is a technology for constructing integrated circuits. CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits...

 technology or a combination of the two (BiCMOS
BiCMOS
BiCMOS is an evolved semiconductor technology that integrates two formerly separate semiconductor technologies - those of the analog bipolar junction transistor and the digital CMOS transistor - in a single integrated circuit device....

). Originally the bipolar circuits provided higher speed but consumed more power than the competing 4000 series
4000 series
The 4000 series is a family of industry standard integrated circuits which implement a variety of logic functions using Complementary Metal–Oxide–Semiconductor technology, and are still in use today. They were introduced by RCA as CD4000 COS/MOS series in 1968, as a lower power and more versatile...

 of CMOS devices. Bipolar devices are also limited to a fixed power supply voltage, typically 5 V, while CMOS parts often support a range of supply voltages.

Milspec-rated devices for use in extended temperature conditions are available as the 5400 series. Texas Instruments also manufactured radiation-hardened devices with the prefix RSN, and the company offered beam-lead bare dies for integration into hybrid circuits with a BL prefix designation.
Regular speed TTL parts were also available for a time in the 6400 series - these had an extended industrial temperature range of −40 C to +85 C. While companies such as Mullard
Mullard
Mullard Limited was a British manufacturer of electronic components. The Mullard Radio Valve Co. Ltd. of Southfields, London, was founded in 1920 by Captain Stanley R. Mullard, who had previously designed valves for the Admiralty before becoming managing director of the Z Electric Lamp Co. The...

 listed 6400-series 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 7400 series 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. Strictly, an integrated circuit made in CMOS is no longer a TTL chip since it uses field-effect transistor
Field-effect transistor
The field-effect transistor is a transistor that relies on an electric field to control the shape and hence the conductivity of a channel of one type of charge carrier in a semiconductor material. FETs are sometimes called unipolar transistors to contrast their single-carrier-type operation with...

s (FETs) and not bipolar junction transistors, but similar part numbers are retained to identify similar logic functions and electrical (power and I/O voltage) compatibility in the different subfamilies.
Over 40 different logic subfamilies use this standardized part number scheme.
  • Bipolar
    • 74 - the "standard TTL" logic family had no letters between the "74" and the specific part number.
    • 74L - Low power (compared to the original TTL logic family), very slow
    • H - High speed (still produced but generally superseded by the S-series, used in 1970s era computers)
    • S - Schottky
      Schottky diode
      The Schottky diode is a semiconductor diode with a low forward voltage drop and a very fast switching action...

       (obsolete)
    • LS - Low Power Schottky
    • AS - Advanced Schottky
    • ALS - Advanced Low Power Schottky
    • F - Fast (faster than normal Schottky, similar to AS)
  • CMOS
    • C - CMOS 4–15 V operation similar to buffered 4000 (4000B) series
    • HC - High speed CMOS, similar performance to LS, 12 nS
    • HCT - High speed, compatible logic levels to bipolar parts
    • AC - Advanced CMOS, performance generally between S and F
    • AHC - Advanced High-Speed CMOS, three times as fast as HC
    • ALVC - Low voltage - 1.65 to 3.3 V, Time Propagation Delay (TPD) 2 nS
    • AUC - Low voltage - 0.8 to 2.7 V, TPD < 1.9 nS@1.8 V
    • FC - Fast CMOS, performance similar to F
    • LCX - CMOS with 3 V supply and 5 V tolerant inputs
    • LVC - Low voltage – 1.65 to 3.3 V and 5 V tolerant inputs, tpd < 5.5 nS@3.3 V, tpd < 9 nS@2.5 V
    • LVQ - Low voltage - 3.3 V
    • LVX - Low voltage - 3.3 V with 5 V tolerant inputs
    • VHC - Very High Speed CMOS - 'S' performance in CMOS technology and power
  • BiCMOS
    • BCT - BiCMOS, TTL-compatible input thresholds, used for buffers
    • ABT - Advanced BiCMOS, TTL-compatible input thresholds, faster than ACT and BCT


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 3.3 V CMOS signals. The non-T parts have conventional CMOS input thresholds.
The ACTQ family introduced by Fairchild utilizes Quiet Series technology to guarantee quiet output switching and improved dynamic threshold performance. FACT Quiet Series features GTO output control and undershoot corrector in addition to a split ground bus for superior performance.
The 74H family is the same basic design as the 7400 family with resistor values reduced. This reduced the typical propagation delay
Propagation delay
Propagation delay is a technical term that can have a different meaning depending on the context. It can relate to networking, electronics or physics...

 from 9 ns to 6 ns 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
Schottky diode
The Schottky diode is a semiconductor diode with a low forward voltage drop and a very fast switching action...

 circuitry, uses more power than the 74, but is faster. The 74LS family of ICs is a lower-power 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
Fairchild Semiconductor
Fairchild Semiconductor International, Inc. is an American semiconductor company based in San Jose, California. Founded in 1957, it was a pioneer in transistor and integrated circuit manufacturing...

 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
Central processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...

 devices.

History



Although the 7400 series was the first de facto industry standard TTL logic family to be second-sourced by several semiconductor companies, there were earlier TTL logic families such as the Sylvania
Osram Sylvania
Osram Sylvania Inc. is the North American operation of lighting manufacturer Osram GmbH, which is owned by Siemens AG. It was established in January 1993, with the acquisition of GTE’s Sylvania lighting division by Osram GmbH....

 SUHL family, Motorola
Motorola
Motorola, Inc. was an American multinational telecommunications company based in Schaumburg, Illinois, which was eventually divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011, after losing $4.3 billion from 2007 to 2009...

 MC4000 MTTL family (not to be confused with RCA CD4000
4000 series
The 4000 series is a family of industry standard integrated circuits which implement a variety of logic functions using Complementary Metal–Oxide–Semiconductor technology, and are still in use today. They were introduced by RCA as CD4000 COS/MOS series in 1968, as a lower power and more versatile...

 CMOS), the National Semiconductor
National Semiconductor
National Semiconductor was an American semiconductor manufacturer, that specialized in analog devices and subsystems,formerly headquartered in Santa Clara, California, USA. The products of National Semiconductor included power management circuits, display drivers, audio and operational amplifiers,...

 DM8000 family, Fairchild
Fairchild Semiconductor
Fairchild Semiconductor International, Inc. is an American semiconductor company based in San Jose, California. Founded in 1957, it was a pioneer in transistor and integrated circuit manufacturing...

 9300 series, and the Signetics
Signetics
Signetics, once a major player in semiconductor manufacturing, made a variety of devices which included integrated circuits, bipolar and MOS, the Dolby circuit, logic, memory and analog circuits. They developed microprocessors like the 2650, the bipolar 8X300 and had licensed Motorola 68000...

 8200 family.

The 7400N quad NAND
Nand
NAND may stand for:*Nand , an Indian classical raga.*Logical NAND , a binary operation in logic.**NAND gate, an electronic gate that implements a logical NAND....

 gate was the first product in the series.

The 5400 and 7400 series were used in many popular minicomputers in the seventies and early eighties. The DEC PDP
Programmed Data Processor
Programmed Data Processor was the name of a series of minicomputers made by Digital Equipment Corporation. The name 'PDP' intentionally avoided the use of the term 'computer' because, at the time of the first PDPs, computers had a reputation of being large, complicated, and expensive machines, and...

 series 'minis' used the 74181
74181
The 74181 is a bit slice arithmetic logic unit , implemented as a 7400 series TTL integrated circuit. The first complete ALU on a single chip, it was used as the arithmetic/logic core in the CPUs of many historically significant minicomputers and other devices.The 74181 represents an evolutionary...

 ALU
Arithmetic logic unit
In computing, an arithmetic logic unit is a digital circuit that performs arithmetic and logical operations.The ALU is a fundamental building block of the central processing unit of a computer, and even the simplest microprocessors contain one for purposes such as maintaining timers...

 as the main computing element in the CPU
Central processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...

. Other examples were the Data General Nova
Data General Nova
The Data General Nova was a popular 16-bit minicomputer built by the American company Data General starting in 1969. The Nova was packaged into a single rack mount case and had enough power to do most simple computing tasks. The Nova became popular in science laboratories around the world, and...

 series and Hewlett-Packard
Hewlett-Packard
Hewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...

 21MX, 1000, and 3000 series.

Hobbyists and students equipped with wire wrap
Wire wrap
Wire wrap is a technology used to assemble electronics. It is a method to construct circuit boards without having to make a printed circuit board. Wires can be wrapped by hand or by machine, and can be hand-modified afterwards. It was popular for large-scale manufacturing in the 60s and early 70s,...

 tools, a 'breadboard
Breadboard
A breadboard is a construction base for prototyping of electronics. The term is commonly used to refer to solderless breadboard ....

' and a 5-volt power supply
Power supply
A power supply is a device that supplies electrical energy to one or more electric loads. The term is most commonly applied to devices that convert one form of electrical energy to another, though it may also refer to devices that convert another form of energy to electrical energy...

 could also experiment with digital logic referring to how-to articles in Byte magazine and Popular Electronics
Popular Electronics
Popular Electronics was an American magazine started by Ziff-Davis Publishing in October 1954 for electronics hobbyists and experimenters. It soon became the "World's Largest-Selling Electronics Magazine". The circulation was 240,151 in April 1957 and 400,000 by 1963. Ziff-Davis published Popular...

which featured circuit examples in nearly every issue. In the early days of large-scale IC development, a prototype of a new large-scale 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 quantity-one pricing for the SN5400 (military grade, in ceramic welded flat-pack
Flatpack (electronics)
Flatpack is a US military standardized Printed-circuit-board surface-mount-component package. The military standard MIL-STD-1835C defines: Flat package...

) was around 22 USD.
As of 2007, individual commercial-grade chips in molded epoxy (plastic) packages can be purchased for approximately 0.25 USD each, depending on the particular chip. Purchased in bulk the price per unit falls even lower.

Part numbering scheme


The part numbers for 7400 series logic devices often use the following naming convention, though specifics vary between manufacturers.
  • First, although sometimes omitted, a two or three letter prefix which indicates the manufacturer of the device (e.g. SN for Texas Instruments
    Texas Instruments
    Texas Instruments Inc. , widely known as TI, is an American company based in Dallas, Texas, United States, which develops and commercializes semiconductor and computer technology...

    , DM for National Semiconductor
    National Semiconductor
    National Semiconductor was an American semiconductor manufacturer, that specialized in analog devices and subsystems,formerly headquartered in Santa Clara, California, USA. The products of National Semiconductor included power management circuits, display drivers, audio and operational amplifiers,...

    ) although these codes are no longer closely associated with a single manufacturer, for example Fairchild Semiconductor
    Fairchild Semiconductor
    Fairchild Semiconductor International, Inc. is an American semiconductor company based in San Jose, California. Founded in 1957, it was a pioneer in transistor and integrated circuit manufacturing...

     manufactures parts with MM and DM prefixes, and none.
  • A two-figure secondary prefix, of which the two most common are "74", indicating a commercial temperature range device and "54", indicating an extended (military) temperature range
  • Up to four letters describing the logic subfamily, as listed above (e.g. "LS" or "HCT").
  • Two or more digits assigned for each device, e.g. 00 for a quad 2-input NAND gate. There are hundreds of different devices in each family. The allocation of device numbers (and, with a few exceptions, the pin-outs) of the original 7400 family was carried across to the later families, and new numbers allocated for new functions, plus some of the competing CD4000
    4000 series
    The 4000 series is a family of industry standard integrated circuits which implement a variety of logic functions using Complementary Metal–Oxide–Semiconductor technology, and are still in use today. They were introduced by RCA as CD4000 COS/MOS series in 1968, as a lower power and more versatile...

     numbers and pin-outs were included over time. There is no pattern to the allocation of these numbers. The function and pin-out of the chip is nearly always the same for the same device number regardless of subfamily manufacturer – exceptions are discussed below.
  • Additional suffix letters and numbers may be attached to indicate the package type, quality grade, or other information, but this varies widely by manufacturer.


For example SN74ALS245N means this is a device probably made by Texas Instruments
Texas Instruments
Texas Instruments Inc. , widely known as TI, is an American company based in Dallas, Texas, United States, which develops and commercializes semiconductor and computer technology...

 (SN), it is a commercial temperature range TTL device (74), it is a member of the "advanced low-power Schottky" family (ALS), and it is a bi-directional eight-bit buffer (245) in a plastic through-hole DIP
Dual in-line package
In microelectronics, a dual in-line package is an electronic device package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be through-hole mounted to a printed circuit board or inserted in a socket.A DIP is usually referred to as a DIPn, where n is...

 package (N).

Many logic families
Logic family
In computer engineering, a logic family may refer to one of two related concepts. A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply...

 maintain a consistent use of the device numbers, as an aid to designers. Often a part from a different 74x00 subfamily could be substituted ("drop-in replacement
Pin-compatibility
In electronics, a pin-compatible device, such as a logic integrated circuit , memory module or microprocessor, is one that has the same functions assigned to the same particular pins....

") in a circuit, with the same function and pin-out 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
4000 series
The 4000 series is a family of industry standard integrated circuits which implement a variety of logic functions using Complementary Metal–Oxide–Semiconductor technology, and are still in use today. They were introduced by RCA as CD4000 COS/MOS series in 1968, as a lower power and more versatile...

 series, for example. But there are a few exceptions where incompatibilities (mainly in pin-out) across the subfamilies occurred, such as:
  • some flat-pack devices (e.g. 7400W) and surface-mount devices,
  • some of the faster CMOS series (for example 74AC)
  • a few low-power TTL devices (e.g. 74L86, 74L9 and 74L95) have a different pin-out than the regular (or even 74LS) series part.
  • five versions of the 74x54 (4-Wide AND-OR-INVERT gates IC
    Integrated circuit
    An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

    ), namely 7454(N), 7454W, 74H54, 74L54W and 74L54N/74LS54, are different from each other in pin-out and/or function!).

Second sources in Europe and the Eastern Block


Some manufacturers such as Mullard and Siemens had pin-compatible
Pin-compatibility
In electronics, a pin-compatible device, such as a logic integrated circuit , memory module or microprocessor, is one that has the same functions assigned to the same particular pins....

 TTL parts but with a completely different numbering scheme, however, data sheets identified the 7400-compatible number as an aid to recognition.

At the time the 7400 series was being made, some European manufacturers (that traditionally followed the Pro Electron
Pro Electron
Pro Electron is the European type designation and registration system for active components .Pro Electron was set up in 1966 in Brussels, Belgium...

 naming convention) such as Philips
Philips
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....

/Mullard
Mullard
Mullard Limited was a British manufacturer of electronic components. The Mullard Radio Valve Co. Ltd. of Southfields, London, was founded in 1920 by Captain Stanley R. Mullard, who had previously designed valves for the Admiralty before becoming managing director of the Z Electric Lamp Co. The...

 produced a series of TTL integrated circuits with part names beginning FJ. Some examples of FJ series are:
  • FJH101 (=7430) Single 8-input NAND gate,
  • FJH131 (=7400) Quadruple 2-input NAND gate,
  • FJH181 (=7454N or J) 2+2+2+2 input AND-OR-NOT gate.


The Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 started manufacturing TTL ICs with 7400 series pin-out in late 1960s and early 1970s. Part numbering 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, 131 series is 74H, 158 series is 74L, 531 series is 74S, 555 series is 74LS, and 1530/1531/1533 are 74F/74AS/74ALS respectively. CMOS elements with TTL pin-out are also available, for example 1564 series is equivalent to 74HC.
  • the function of the unit is described with a two-letter 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 JK-triggers, decimal and binary counters, etc.
    • the number distinguishes variants with different number of inputs, or different number of elements within a die - ЛА1/ЛА2/ЛА3 (LA1/LA2/LA3) are 2 four-input / 1 eight-input / 4 two-input NAND elements respectively (equivalent to 7420/7430/7400)

Before July 1974 the two letters from the functional description were inserted after the first digit of the series. Examples: К1ЛБ551 and К155ЛА1 (7420), К1ТМ552 and К155ТМ2 (7474) are the same ICs made at different times.

Clones of the plain 7400 series were also made in other Eastern Block countries
  • Poland
    Poland
    Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

     and Czechoslovakia
    Czechoslovakia
    Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...

     used the 7400 numbering scheme with manufacturer prefixes UCY and MH respectively. Examples: UCY7400, and MH7400.
  • Hungary
    Hungary
    Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...

     also used the 7400 numbering scheme but with manufacturer suffix - 7400 is marked as 7400APC.
  • Romania
    Romania
    Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...

     used trimmed 7400 numbering with own manufacturing prefix CDB. Example: CDB4123E is 74123.
  • East Germany 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.

No information is available for technology modifications (74H, 74LS, etc.) manufactured outside USSR.

See also

  • List of 7400 series integrated circuits
  • 4000 series
    4000 series
    The 4000 series is a family of industry standard integrated circuits which implement a variety of logic functions using Complementary Metal–Oxide–Semiconductor technology, and are still in use today. They were introduced by RCA as CD4000 COS/MOS series in 1968, as a lower power and more versatile...

  • List of 4000 series integrated circuits
  • Logic gate
    Logic gate
    A logic gate is an idealized or physical device implementing a Boolean function, that is, it performs a logical operation on one or more logic inputs and produces a single logic output. Depending on the context, the term may refer to an ideal logic gate, one that has for instance zero rise time and...

  • Open collector
    Open collector
    An open collector is a common type of output found on many integrated circuits . Instead of outputting a signal of a specific voltage or current, the output signal is applied to the base of an internal NPN transistor whose collector is externalized on a pin of the IC. The emitter of the...

  • Logic family
    Logic family
    In computer engineering, a logic family may refer to one of two related concepts. A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply...

  • Pin-compatibility
    Pin-compatibility
    In electronics, a pin-compatible device, such as a logic integrated circuit , memory module or microprocessor, is one that has the same functions assigned to the same particular pins....