Second Sources in Europe and The Eastern Bloc
Some manufacturers such as Mullard and Siemens had pin-compatible 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 naming convention) such as Philips/Mullard 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 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 Bloc countries
- Poland and Czechoslovakia used the 7400 numbering scheme with manufacturer prefixes UCY and MH respectively. Examples: UCY7400, and MH7400.
- Hungary 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 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 D2; e.g. D200 = 74LS00. In later years East German made clones were also available with standard 74* numbers, usually for export.
No information is available for technology modifications (74H, 74LS, etc.) manufactured outside USSR.
Read more about this topic: 7400 Series
Famous quotes containing the words sources, europe, eastern and/or bloc:
“No drug, not even alcohol, causes the fundamental ills of society. If we’re looking for the sources of our troubles, we shouldn’t test people for drugs, we should test them for stupidity, ignorance, greed and love of power.”
—P.J. (Patrick Jake)
“For it does not follow because many books are written by persons born in America that there exists an American literature. Books which imitate or represent the thoughts and life of Europe do not constitute an American literature. Before such can exist, an original idea must animate this nation and fresh currents of life must call into life fresh thoughts along its shores.”
—Margaret Fuller (1810–1850)
“I need not tell you of the inadequacy of the American shipping marine on the Pacific Coast.... For this reason it seems to me that there is no subject to which Congress can better devote its attention in the coming session than the passage of a bill which shall encourage our merchant marine in such a way as to establish American lines directly between New York and the eastern ports and South American ports, and both our Pacific Coast ports and the Orient and the Philippines.”
—William Howard Taft (1857–1930)
“Unpleasant questions are being raised about Mother’s Day. Is this day necessary? . . . Isn’t it bad public policy? . . . No politician with half his senses, which a majority of politicians have, is likely to vote for its abolition, however. As a class, mothers are tender and loving, but as a voting bloc they would not hesitate for an instant to pull the seat out from under any Congressman who suggests that Mother is not entitled to a box of chocolates each year in the middle of May.”
—Russell Baker (20th century)