[SI-LIST] : Low Voltage CMOS question

Bill Dempsey (bdempsey@dnaent.com)
Thu, 01 Apr 1999 14:29:03 -0600

To all:

I hope this question is not too far off topic -- as it seems most of
you have IC design experience that's relevant.

My question is concerning "maximum" operating voltage of "low voltage"
CMOS parts (74xx family). I'm aware that these LVC parts have different
input thresholds from say 5V CMOS. But can't they still operate at a 5V
VDD? Doesn't the trigger voltage (threshold) voltage scale
proportionally to the VDD applied? I'm curious because I really want
to operate some LVC parts at this voltage and can't get a good answer
from the semiconductor help line (TI) that explains why or why not this
would work. Is the output transistor pair setup identically to 5V CMOS
parts? I have been doing this experimentally and see no obvious reason
why I'd have longterm failures.

Comments?

Thanks,

Bill

**** To unsubscribe from si-list: send e-mail to majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE si-list, for more help, put HELP. si-list archives are accessible at http://www.qsl.net/wb6tpu/si-list ****