Gary Poole

9S08AC16 Temperature Sensor Voltage

Discussion created by Gary Poole on Oct 1, 2008
Latest reply on Oct 1, 2008 by bigmac
Hi All

I've just migrated up from an 08QG8 to an 08AC16 part and was wondering why i was getting wildly inaccurate temperature readings from the internal temperature sensor using imported 08QG8 code.

Anyway, i found out the reason - there's been a subtle change in the temperature sensor reference voltage @25°C from 0.7012 to 1.41mV.

However, the footnote for this value states "Typical values assume VDDAD = 5.0V, Temp = 25C, fADCK=1.0 MHz unless otherwise stated. Typical values are for reference only and are not tested in production".

So my question is this, has this value been definitively determined yet for various values of VCC  etc. I based my original 08QG8 code around AN3031, unfortunately, this now appears obsolete for 08AC16 use.