On Sun, 16 Aug 2009 01:06:12 +0200, clipka <ano### [at] anonymousorg> wrote:

>Stephen schrieb:
>>> What voltage does CMOS use anyway? IIRC, TTL can be driven with a 
>>> triplet of 1.5 V batteries.
>> 
>> Why don't you look it up as I can't remember,
>
>74HCxx: 2V to 6V (i.e. a doublet or triplet of 1.5 V batteries will do 
>fine, even when quite depleted already)
>
>74HCTxx: 5V, +/- 0.5V (i.e. a triplet will probably do quite well if 
>still good)
>
>Power consumption is virtually zero at low frequencies.

An example: Around 1975 I made a digital clock out of TTL and the power
consumption was 20 amps. About 1977 I made another using CMOS, it ran for years
on a PP3 battery.
-- 

Regards
     Stephen

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