Low temperature effect?

[pinoy]

Hi, is the low temperature has an effect on your signal integrity for a high frequency signal? (above 40MHz)

For example you soak your circuit at -40degC? What happen to the high frequency signa? (will it have jitter, delay, overshoot, undershoot, etc?)

 

[master_picengineer]

Nice question,

I think since T decrease then R rise so RC rise also then skew and delay also.
Jitter remain the same.

 

[pinoy]

It's maybe true in high temp.... but.... how about for low temp? R value will not increase at low temp....

 

[master_picengineer]

Sory, I mean when T decrease !

 

[pinoy]

I think as temperature increases, resistance increases...

Please refer to URL:
**broken link removed**

Thanks

 

[master_picengineer]

Let clarify this point pinoy.
R increase when T increase and vice versa in Metals (All Conductors).
R decrease when T increase and vice versa in semiconductors.

Added after 15 minutes:

If only we consider the signal:
Signal in a Metal Wire: T increase , R increase and vc. vs so Delays increase

Signal in a Semiconductor: T inc, R dec and vc vs so Delays dec.

We have to not ignore the impact of temperature on Transistors which controle and generate signal.