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What is the effect of low temperatures on semiconductors

What is the effect of low temperatures on semiconductors

What is the effect of low temperatures on semiconductors

(OP)
I am considering a mass market measurement device which involves exposure of a semiconductor chip to outside temperatures, ranging from -30 degrees C. to +40 degress C.

The semiconductor would have to act as a microprocessor, having these needs:

1) Provide an accurate clock pulse with outside recalibration only once in six months.
  
2) Store up to 4 MB of data.

3) Dump data at a high rate whem demanded to a host sytem.  (Say 4 MB in 3 seconds)

4)Be powered by a watch size battery power source or smaller if possible.

The device I am considering is for a high volume application, so the cost could be significant

What type of semiconductor provides the best stability for temperature ranges?  

What about battery material, at what temperature does a tiny battery lose its oomph due to the nature of low ambient temperature on the chemical reaction taking place in the battery?

Thank you for whatever light you can shed on this idea.

RE: What is the effect of low temperatures on semiconductors

You would need to identify a microprocessor that is available in an "industrial" or "automotive" temperature range, i.e. down to about -40C (up to +85C). Standard commercial parts are typically only guaranteed to operate to spec down to 0C. Other parts, as well, would need to be tested, or guaranteed, to operate at low temp such as the oscillator you'd use. None of this should be too challenging (although I can't speak for the battery) since automotive electronics encompass lots of the properties you've specified.

RE: What is the effect of low temperatures on semiconductors

Lithium is your best bet for sub-zero operation.
I'm not sure of your definition of semiconductor.
When you state "The semiconductor would have to act as a microprocessor..." it sounds as though you are asking for a PROM of varying flavors. Is it a "One-Chip" solution you are looking for? If so, you may consider a PAL, PLA, or other fully programmable logic packages. Maybe a high-end PIC, but I doubt it.
The data xfer speed is realistic in normal applications, but with the limited power available in your application, I'm not too sure. How far away from the storage appliance location will the dataloggers be? Will they be wired or wireless?
Sounds like a neat project :)!
Foxfur

RE: What is the effect of low temperatures on semiconductors

My previous employer rated completed high volume units down to this temperature although it violated several temp ratings of semiconductors. We tested them in a temp chamber and they worked successfully. I did NOT agree with their temp ratings on the completed units. Just because one works at that temp does not mean the next one will. Everyone has told you the advice I would give to you. You can calculate the life of a lithium battery at the reduced temperature. If it is acceptable then so be it if it is not you may require users to change the battery every x days/years. Good luck.

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