Re: op-amp nV input offset voltage

Pieter wrote:

> To prevent thermoelecric voltages, keep all pins at the same
> temparature. But also all surrounding resistors etc. A cooling airflow
> gives temperature differences. And resistors and opamps that get warm
> may give some effects.
> 
> Pieter

This is especially true of temperature gradients across devices that 
aren't metallic throughout, e.g. metal oxide resistors and 
semiconductors.  The thermocouple constants between silicon and any 
metal are up in the 700-1500 mV/K range, depending on doping---which 
dwarfs the slope of any metal/metal thermocouple.

Cheers,

Phil Hobbs