Hi,
I'm using the ADS1248 to sample some sensors, however I was keen to also use it to measure the ambient temperature of the chip/system to perform some basic calibration for these sensors.
I have successfully got the ADC sampling the sensor voltages and it appears to work OK.
However I'm having trouble sampling the internal ambient temperature sensor.
I'm using the internal reference, and by using the same code I use for my normal sampling (with the only change being to MUX1 set to 0x33 instead of 0x30).
The data I get out doesn't make sense, I get about 3,000,000 out from this measurement. Which is about 732 mV. I subtract 118 mV from this and divide by 405 uV and then add 25 C and I get thousands of degrees.
Am I missing something here?
UPDATE: I tried blowing cold air onto the chip while sampling this value and it began to rise.... up to about 3,150,000.. (no idea what the temperature change would have actually been, a few degrees I suppose?)
Regards,
Kyle
(I edited out my second question about voltage references, I didn't realise it but I was setting these references up properly)
