On Sat, 05 Mar 2011 16:29:48 +0000, Skipweasel wrote:
Much 74LS series is OK up to around 7V. Most data sheets say 5.5V, but a
few actually admit to more - but experience suggests that above 7V
you're /really/ pushing your luck.

I've had a system built largely around LS-TTL survive 9V before. I was
rather surprised that nothing fried.