TSUP on MM912J637

[igw]

Hello all,

The MM912J637 has a low current voltage output intended to drive an external temperature sensor, TSUP, as well as a dedicated ADC.

The specs for TSUP show a +/-5% variation around the nominal 1.25V.

I am wondering if I need to account for this voltage tolerance in my temperature accuracy calculations *or* if the TSUP voltage is related to the ADC's VREF.

So, in effect my question is, is the ADC doing a ratiometric or absolute measurement on the voltage at VTEMP.

How closely does TSUP track VREF is probably the most telling specification (and is not in the datasheet)?

Thanks,

Ian

[TomasVaverka · Accepted solution]

Hello Ian,

The reference of the External Temp Sensor is TSUP.

This means that for external temperature measurement the variation of TSUP will not impact the measurement.

Regards,

Tomas