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CMOS vs TTL? Which Is Better? Answered

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What are the main differences between CMOS (Complementary Metal-Oxide-Semiconductor) and TTL (Transistor-Transistor-Logic).

The things I want to know:
  • Which type do you use?
  • Which kind do you prefer?
  • Which type do today's computers use?
  • Are CMOS and TTL compatible?
These are the few things I know about them:
  • CMOS ICs (overall) will draw less current compared to TTL
  • CMOS are less picky in regard to their voltage supply.
  • It seems like most people like CMOS more than TTL.
Thanks!

Comments, answers, and everything else is appreciated!

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steveastroukBest Answer (author)2011-03-01

You're way out of date ! TTL: died out years ago, to be replaced with LS, ALS and F series, or even HC series logic.

4000series CMOS has a special place, because its extremely low power consumption and wide supply range, at the expense of speed - CMOS tops out at not much more than 1 Meg.

Try this Wikiarticle
http://en.wikipedia.org/wiki/Logic_family

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jensenr30 (author)steveastrouk2011-03-01

so do you think the F series is ok to use? i have a few F series chips and they are working good so far. They are cheap and can get into the hundreds of MegaHertz range.

I guess what I'm asking is this: are F series chips acceptable?

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steveastrouk (author)jensenr302011-03-01

What do you mean by "acceptable" depends on what you want to do ! Interface to a multi gig CPU and 4000 series wouldn't work, but F series won't run on a lemon battery.

TTL is DEAD. "Cmos" is what we use inside most modern processors anyway, "4000" series is Cmos, but its not all there is.

Steve

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jensenr30 (author)steveastrouk2011-03-02

Thank you for prompt replies and your advise. It 'shant be wasted!

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orksecurity (author)steveastrouk2011-03-01

+1. Note that there are versions of the newer CMOS chips which have input/output circuits compatible with old TTL chips, if you want to continue playing with them.

CMOS is much less static-sensitive than it used to be -- I regularly handle CMOS electronics, including expensive PC components, without worrying much about it -- but a grounding strap (see much discussion in the past) is good cheap insurance.

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jensenr30 (author)2011-03-01

awesome! thanks for the in-depth answer! this helped alot, man!
I'm selecting this as the best answer!

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jensenr30 (author)2011-03-01