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Unread 04-25-2003, 01:27 PM   #25
Since87
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Join Date: Sep 2002
Location: Indiana
Posts: 834
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Quote:
Originally posted by unregistered

any way at all to get better resolution ??
Not using the MAX6655.

The part only has an 11 bit ADC and one of those bits is a sign bit.(positive or negative)

The way they have it setup, the part can output data representing -128C to +127.875C. (Spec'd operating range appears to be -55C to +125C.)

Looking only at the positive range, and dropping the ADC's sign bit, the resolution can be calculated at:

127.875 / ( 2^10 - 1 ) = 127.875 / 1023 = 0.125C

Maxim would either have to use a higher resolution ADC or shrink the range of temperatures that can be encoded. Either's unlikely due to marketing considerations. (It's too bad they didn't leave off the negative part of the temperature range, and double the resolution on the positive range.)

Replacing the Maxim IC with a homebrew setup is a possibility, but it would be very expensive by comparison.
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