Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site dciem.UUCP Path: utzoo!dciem!king From: king@dciem.UUCP (Stephen King) Newsgroups: sci.electronics Subject: Re: TTL Questions Message-ID: <2405@dciem.UUCP> Date: Tue, 25-Aug-87 08:29:33 EDT Article-I.D.: dciem.2405 Posted: Tue Aug 25 08:29:33 1987 Date-Received: Thu, 27-Aug-87 04:44:56 EDT References: <7105@alice.UUCP> <764@sol.ARPA> <128@umich.UUCP> <15370@onfcanim.UUCP> <739@aplvax.UUCP> Reply-To: king@dciem.UUCP (Stephen King) Organization: D.C.I.E.M., Toronto, Canada Lines: 22 Keywords: TTL, pullups Summary: I have been designing and building TTL circuits for some time and I have never experienced any problem with LS, S, ALS, F series parts with inputs tied high/low WITHOUT resistors. I always distribute a lot of capacitance around my circuits, so VCC is not noisy, and with proper power supplies never will be. For the sake of argument, I scanned some of the schematics I have for multibus cards built by a prominent manufacturer (who shall remain nameless). In NO instance does this manufacturer uses pull- ups. All sorts of things are tied high/low in all sorts of circuits. I looked at CPU cards, memory boards, video cards, frame grabbers, the works. These items have functioned flawlessly for about three years now, as have many of my circuits (the remainder have simply fallen into disuse). So, there's my $0.02 worth. .......................sjk -- * Defence & Civil Institute * ...!utzoo!dciem!king * of Environmental Medicine * Stephen J King - Simulation & Training Group - (416) 635-2149