No subject

the temperature increases effective electron
mobility (makes transistors run faster),
increases transistor gains and decreases
device noise.  These are generally good
things.  Often, once all other tests are
complete, a chip designer will cool their
chip as much as possible and 'see how this
baby can really perform'.

On the negative side, temperature reductions
in analog circuits will alter the operating
points of each transistor.  The bias circuits
will typically compensate for this change and
keep the circuit operating.  There may be a
temperature below which the bias circuits
reach the limit of their drive capacity and the
device stops working.  Related to this
temperature shifts can also change the
voltage thresholds at which circuits switch.

In summary.  It is possible that a circuit
may stop working at a low temperature.  It
is also possible that the circuit will
operate better at a low temperature.  One
can only tell by trying it out, or by doing
a detailed analysis of the design.

Hope there was some useful information in this.

Regards
John


References:  If interested, you can read more
in the following book:
"Principles of CMOS Design" by Weste and Eshraghain

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