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I'm looking for an IC that takes a signal and sends it to one of four possible outputs. So I came across a 2-to-4 demultiplexer which does just that. 74139 series to be precise. However, they all seem to be active LOW and what I need is an active HIGH IC. It seems an IC should exist, however, I can't for the life of me find one. I understand that I can just invert the outputs using a 7404 IC, but I would like to use less chips if possible. It just seems to me that if an active LOW exists, then shouldn't an active HIGH option exist as well? I mean, anytime I come across an explanation of how a 2-to-4 demultiplexer works, they always show an active HIGH diagram rather than an active LOW. It's not the end of the world if it doesn't, but thought I'd ask here to see if anybody knows more about this. Thanks!

asked 2 days ago

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  • \$\begingroup\$ "if A exist, B must exist too" is a fallacy. Also, we don't do product recommendations! \$\endgroup\$

    2 days ago

  • \$\begingroup\$ Use a 74HCT238 3-to-8 decoder and tie one of its inputs low. \$\endgroup\$

    2 days ago

  • \$\begingroup\$ I understand that it doesn't have to exist, I just don't understand why it doesn't exist. It seems to me that it should exist. You don't need to recommend a product, but you can talk about ICs and what they do, right? \$\endgroup\$

    2 days ago

  • \$\begingroup\$ The first TTL series were only "decoders" ... The next were also "demultiplexers". Little difference, but more interesting with same pin number. \$\endgroup\$

    2 days ago

  • \$\begingroup\$ but you can talk about ICs and what they do, right? - no, you need to ask a specific answerable question and, I just don't understand why it doesn't exist isn't enough to produce an answer that is anything other than an opinion. Questions that solicit opinions are usually closed because of this: This question is likely to be answered with opinions rather than facts and citations. It should be updated so it will lead to fact-based answers. - this site has these rules for a reason and, if you would like to raise a question about them try here. \$\endgroup\$

    2 days ago

1 Answer 1

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It is certainly true that a decoder with active-high outputs could exist. I will assert that such a thing does exist, and defy anyone to prove me wrong.

You can't ask me to prove that I'm right by providing an example because that would make this a product recommendation, which is off-topic.

answered 2 days ago

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  • \$\begingroup\$ +1 for your infallible logic lol \$\endgroup\$

    2 days ago

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