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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!

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    \$\begingroup\$ "if A exist, B must exist too" is a fallacy. Also, we don't do product recommendations! \$\endgroup\$ Dec 18, 2021 at 14:57
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    \$\begingroup\$ Use a 74HCT238 3-to-8 decoder and tie one of its inputs low. \$\endgroup\$ Dec 18, 2021 at 15:06
  • \$\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\$ Dec 18, 2021 at 15:11
  • \$\begingroup\$ The first TTL series were only "decoders" ... The next were also "demultiplexers". Little difference, but more interesting with same pin number. \$\endgroup\$
    – Antonio51
    Dec 18, 2021 at 16:07
  • \$\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\$
    – Andy aka
    Dec 18, 2021 at 16:53

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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.

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    \$\begingroup\$ +1 for your infallible logic lol \$\endgroup\$
    – Andy aka
    Dec 18, 2021 at 16:50

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