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[email protected] stratus46@yahoo.com is offline
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Default Can I substitute a 74HC75 for a 74LS75?

On Dec 10, 12:18*pm, Tony Miklos wrote:
Actually I have done it and it is working, but can it be expected to
last? *Or should I order some LS's and install what was originally in it?

If it matters, it's being used on a video arcade game mother board, Ms
Pac-Man to be specific.

Thanks,
Tony


CMOS chip inputs must be tied hi or low so that they don't drift into
linear mode pull excess current and get hot. Any unused input that is
NOT connected should be tied to + 5. Unconnected output pins can be
ignored. You may run into quirks if they were pushing to the edge of
the clock speeds. An HCT chip has the input thresholds more closely
matched to TTL and may work better.