I wonder what series of 3.3V CMOS logic gates are the standard in the year 2015.

Decades ago, when I learned about digital logic the 7400 TTL series was just going out of favor for the CD4000 series.

I haven't used any bare CMOS logic gates and flip-flops since then except for toy stuff. Now I'm working on a design where I need some digital logic. The prototype is running using a CPLD, but that seems to be a bit overkill. The design is so small that I can fit it inside three or four logic chips.

Timing and current consumption aren't critical at all. Low price and high availability are more important.

So what kind of digital logic family is the industry using these days?

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    \$\begingroup\$ I don't know if you can really talk about standards for nieche applications, in a world where everyone throws micros at all problems. \$\endgroup\$
    – PlasmaHH
    Aug 14, 2015 at 13:54
  • \$\begingroup\$ 7400 TTL never went out of favour for CD4000 series, they operated in entirely different niches (high speed vs low power). What DID happen was the development of new family 74HC (T, ACT, FCT etc) which combined the speed (and 5V downwards operation) of one with the low power of the other, and covering the range of both families (hence some were numbered 74HC40xx...) These families are (somewhat) still around. \$\endgroup\$
    – user16324
    Aug 14, 2015 at 14:06
  • \$\begingroup\$ @PlasmaHH I don't think I can justify a micro just for a 2 stage frequency divider and a 8 to 1 multiplexer :-) \$\endgroup\$ Aug 14, 2015 at 14:50
  • \$\begingroup\$ @NilsPipenbrinck: some people can do, especially if that is only a modular part of a circuit \$\endgroup\$
    – PlasmaHH
    Aug 14, 2015 at 14:54

1 Answer 1


HCMOS (74HC) is still very popular these days due to its wide voltage range and the fact that it still has through-hole packages, but LVC (74LVC) is useful for its lower bottom supply limit, 5V tolerance regardless of supply, partial power-down capability, reduced footprint packages, and reduced gate count devices (e.g. 74LVC2G00).

  • \$\begingroup\$ Based on availability, AHC (Advanced High-Speed CMOS) is also fairly popular. It is offers many of the same features as LVC such as 5V-tolerant inputs and a wide supply range. It also runs at ~3x the speed of HC without excessive switching noise (a major problem with 74AC). However, AHC is typically a little bit slower than LVC at 3.3V. \$\endgroup\$ Dec 23, 2017 at 6:00

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