Thermistor Voltage Supply Question

Use a current mirror(google) to feed each termistor.

Sorry stupid question... all the inputs would be connected to the same point. Duh.

to

Best is to use a Wheatstone bridge, and amplify the imbalance between two legs (sense leg =3D +V through 47k pullup to tap, from tap to GND through thermistor). The reference leg of the bridge is at the ADC (so resistors match in temperature) and the sense leg is at the to-be-sensed temperature. That way, your sensors can be individually tuned for a common 'zero' point with adjustments to their pullups. The bridge amplifier (just about any slow op amp will do fine) will boost the temperature signal to, ideally, a few volts so the ADC has good temperature resolution.

This requires three wires, though, to the sensor. Other sensor types that make a two-wire solution, like AD590 or a diode-connected transistor, might be suitable, too.

yes, use a CD4016 or similar to steer the current to the desired thermistor before reading it. (unless you're interested in measuring how well insulated the thermistor is)

if you don't have control over when the device takes readings from the thermistors this probably won't work.

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