[sdiy] SSM2164 and *one unit* tempco idea!

[karl dalen]

Idea!

In order to compensate for the temp drift in the SSM2164 one usually takes
a tempco, or ntc for each expo,but since here all the expos are on the same
die and therefore (not matched) but at least on the same die close they
would be quite equal in terms of temp drift one could take one tempco/ntc
thermally place it in contact with the top SSM2164 or below (missionary sex
formation) then take the sensed value, scale it to match each expo input and
then simply add this drift coefficient to each expo input.

The idea are instead of having four tempcos (which would be expensive)
you can use one dirt cheap NTC for instance, if the NTC bails the entire 
chip will bail instead of having to figure out which OTA of four or more bails
out in the case of using four NTC's.Also you save components, and PCB
real estate and its cheaper!

Ideas about this idea!

Reg
KD


	
	
		
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