[sdiy] CMOS & CD4007 Questions?

[Magnus Danielson]

From: "Jay Schwichtenberg" <jays at aracnet.com>
Subject: [sdiy] CMOS & CD4007 Questions?
Date: Wed, 27 Nov 2002 10:54:05 -0800

> I have some questions about some of the CMOS chips and the CD4007 that we
> use. A number of the 'logic' chips we use in oscillators (inverters), cmos
> in the analog domain and as switchs/muxs (4016, 4066, 4051) have a number of
> little quirks that vary between manufactures. I read and hear: only use so
> and so's chip here, don't use XXXX's chip, have to select chips......
> 
> Then there is the CD4007 which falls between the analog and digital realm,
> more than most the other chips. A number of manufactures spec it and
> application notes use it in the analog domain. So my main question is how
> consistant is the CD4007? Are there issues with different manufactures chips
> working different?

The issue is that the CD4007 is really a kind transistor array done in the same
productionline as all the other CMOS stuff. It is hardly so that these chips
are made to have a very tight analog specs. They are meant to be a little more
"open" than your normal CMOS inverter, but if you want quality CMOS transisors,
please look elsewhere.

Also, processes might be slightly different and also changes with time. It's
like baking bread, you don't really get the same result as last time.

Cheers,
Magnus