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???
12/20/06 16:38
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 		 #129832 - 74HCTMOS does not contain internal pull-ups
Responding to: ???'s previous message
Erik said:
...but did the LS not have a higher "input pullup" (required current to accept a high) than HCT?

Not sure whether having you understood corectly. But only the 74LS-TTL has an internal pull-up resistor. The 74HCTMOS does not.

Kai

List of 45 messages in thread
TopicAuthorDate
Why would the OLD part get hot?            01/01/70 00:00      
   Could be            01/01/70 00:00      
      just to focus ...            01/01/70 00:00      
         Current consumption?            01/01/70 00:00      
      HMOS            01/01/70 00:00      
         Yes, they were warm ...            01/01/70 00:00      
            some special mode?            01/01/70 00:00      
               I know            01/01/70 00:00      
               I doubt there\'s a special mode involved            01/01/70 00:00      
                  BI NGO!            01/01/70 00:00      
                     Not yet, my friend ... but you\'re onto something            01/01/70 00:00      
                        doen memory lane            01/01/70 00:00      
                           it's all pretty confusing            01/01/70 00:00      
                              they all did            01/01/70 00:00      
   well ... the REAL question is ...            01/01/70 00:00      
   Have you tried using slow SRAM...            01/01/70 00:00      
      How about....            01/01/70 00:00      
         I'm not sure what that will tell me.            01/01/70 00:00      
      What do you believe that would do?            01/01/70 00:00      
         Step Back            01/01/70 00:00      
            Well, that's how it is ...            01/01/70 00:00      
   Some hints            01/01/70 00:00      
      Yes, that\'s so ...            01/01/70 00:00      
         Maybe            01/01/70 00:00      
            Intel doesn\'t care ...            01/01/70 00:00      
            O.K. ... so here\'s what I\'ve found ...            01/01/70 00:00      
               do you want to be stylish?            01/01/70 00:00      
                  Bipolar logic? Maybe            01/01/70 00:00      
                     Back in the day            01/01/70 00:00      
                        Pull-ups            01/01/70 00:00      
                           Dynamic logic may be the reason for the hot part            01/01/70 00:00      
                           That's what I find confusing            01/01/70 00:00      
                              pullups HCT and LS            01/01/70 00:00      
                                 74HCTMOS does not contain internal pull-ups            01/01/70 00:00      
                                 emitters vs resistors            01/01/70 00:00      
                           So, Kai, How did you arrive at 10K-ohms?            01/01/70 00:00      
                              No calculations, just a compromise            01/01/70 00:00      
                                 I haven't tried it with LS parts ... yet ...            01/01/70 00:00      
                                    throw away that databook :-)            01/01/70 00:00      
                                       Well, it's the old TTL book from TI ...            01/01/70 00:00      
                                          just a thought re LS pullup            01/01/70 00:00      
                                             That's the HCTLS from Samsung            01/01/70 00:00      
                        re: back in the day            01/01/70 00:00      
                           What about P2?            01/01/70 00:00      
                              No Just P0            01/01/70 00:00      

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