Talk:7400 series
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Could someone do more research on the different families of logic? http://www.ti.com/ (http://focus.ti.com/logic/docs/technologyfamily.tsp?templateId=5985&navigationId=11386&DCMP=TIHomeTracking&HQS=Other+OT+home_p_logictechfam) has an extensive list of logic families. Also, additions like the 'A' prefix sometimes means Advanced, and the 'H' suffix means bus hold, etc. could be improved. Mhowell 14:25, 17 October 2005 (UTC)
List of 7400 series parts doesn't really belong in Talk; moved to list of 7400 series integrated circuits. --Brouhaha 16:24, 29 Sep 2004 (UTC)
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[edit] Minicomputers Using 7400 series TTL
The 74181 was the 'workhorse' of the minicomputer era. It was the function generator for machines like the:
[edit] History
The main page states that the 7400 was available in 1962. I believe this is incorrect. I'm pretty sure that it was introduced around 1966-1967, but I don't have an authoritative reference. Note that there were other TTL parts before the 7400 series (e.g., the Motorola MTTL 4000 series, not to be confused with the CD4000 CMOS series). --Brouhaha 15:23, 29 Sep 2004 (UTC)
Updated introduction date to 1965; I've found two references to TI introducing the SN7400 series in that year, although neither could be considered extremely authoritative. The only logic *family* in 1962 was Motorola MECL. I'm not sure whether the "nearly $1000" price is accurate, nor the engineer's typical salary. --Brouhaha 23:49, 4 Oct 2004 (UTC)
Removed $1000 claim. I've spoken to engineers that were designing computers in 1965, and they say the early SN7400 prices were well under $100, possibly under $25. --Brouhaha 19:50, 18 Jan 2005 (UTC)
I removed the following paragraph as it has NOTHING to do with 7400 series TTL, which was not used in the Minuteman II:
The computer for the Minuteman II missile used integrated circuits in such large quantities that the prices fell to only $15 per package of four gates, paying for the difficult new lithographic assembly lines, and enabling the sharply-reducing prices of the modern digital computer.
--Brouhaha 23:49, 4 Oct 2004 (UTC)
[edit] Transistor Count?
From the diagram, am I correct in thinking this product had only 4 transistors in it?
- MSTCrow 18:30, 17 March 2006 (UTC)
- No, the diagram shows 4 NAND gates. Each gate is implemented in typically 4 transistors (a few more for AND, NOR, OR gates etc) for a total of 16 transistors in the 7400. Four of these transistors has two emitters in it, so you might want to count those as say 1.3 transistors (4 connections to the usual 3). An eight input NAND gate (7430) has just 4 transistors, but one of these has 8 emitters (which you might want to count as 10/3, so only about 6.3 transistor equivalents in that one. These are the SSI chips (small scale integration). Things like the 7490 counter are called MSI (medium scale integration), they have maybe a hundred transistors in them. --Mike Van Emmerik 22:30, 17 March 2006 (UTC)
[edit] pictures
Do the pictures of the homebrew projects add anything to the article? They seem irrelevant to me. -- Mikeblas 11:52, 26 March 2007 (UTC)
