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- Newsgroups: sci.electronics
- Path: sparky!uunet!mcsun!Germany.EU.net!ira.uka.de!chx400!bernina!isibee3!stettbac
- From: stettbac@isibee3 (Juerg Stettbacher)
- Subject: Re: substitution of logic families
- Message-ID: <1992Sep7.144608.6033@bernina.ethz.ch>
- Sender: news@bernina.ethz.ch (USENET News System)
- Organization: Swiss Federal Institute of Technology (ETH), Zurich, CH
- X-Newsreader: Tin 1.1 PL5
- References: <1992Sep4.191635.9804@mnemosyne.cs.du.edu>
- Date: Mon, 7 Sep 1992 14:46:08 GMT
- Lines: 26
-
- Gary huntress (ghuntres@nyx.cs.du.edu) wrote:
- :
- : Can LS, ALS, and CMOS (pin compatible) components be substituted
- : for TTL parts in general? I've got an "old" TTL system that needs
- : a couple of spare parts, do I need to agonize over speed, power, fan out
- : rise times.......or are the newer logic families always "better"?
- :
-
-
- Hi Gary
-
- In most cases you can. Simply choose one of the following
-
- 1. Just try.
- 2. Have a look at the introduction of a logic data book
- such as National or (.. what ever).
-
- Be careful with 74Fxx types. They produce very sharp edges and can
- cause trouble. For all common applications LS, ALS, HCT are equivalent
- and ok.
-
- The TTL and CMOS mix works from CMOS output to TTL input, but not vice
- versa. (In fact it may work, but there is no guarantee, so forget about.)
-
-
- juerg at ethz switzerland
-