17 Jan
1999
17 Jan
'99
5:18 a.m.
Once upon a midnight dreary, Tony Duell had spoken clearly:
The main difference is the power consumption. The CMOS
version takes a
much lower supply current (even when selected).
There may also be differences in the access time (but fast enough CMOS
EPROMs exist) and the programming algorithm (but that only matters to the
programmer).
They are essentially pin/function compatible.
Erm, correct me if I'm wrong ('cause I may very well be) but at least in
comparison with 4xxx CMOS vs. 74xx TTL, not only do the require less power
to do their job, but they can also *provide* less power on their outputs to
other chips' inputs, right?
Do CMOS eproms suffer the same limitation? If so, if the bus that the eprom
is on is totally unbuffered and trying to feed too many input gates on the
bus, a CMOS might not work and may require something non-CMOS; or if all
you have is CMOS, you might have to build a daughtercard to fit in the
eprom socket with the CMOS eprom & buffers...
If not, [obviously] nevermind. ;-)
Just a thought,
Roger "Merch" Merchberger
--
Roger "Merch" Merchberger --- sysadmin, Iceberg Computers
Recycling is good, right??? Ok, so I'll recycle an old .sig.
If at first you don't succeed, nuclear warhead
disarmament should *not* be your first career choice.