Temperature Sensor Front-End Calculator
Design an NTC or PT100/PT1000 front-end (resistor divider or constant current) and see the output voltage vs temperature, sensitivity, and ADC resolution.
Updates live as you change the inputs.
Turning a sensor's resistance into a voltage
A temperature sensor is a resistance that changes with temperature. To read it with an ADC you convert that resistance to a voltage — most often with aresistor divider (a fixed pull-up resistor in series with the sensor) or a constant-current source (which gives a voltage directly proportional to resistance).
Divider: Vout = Vs · R / (R + Rf)
Constant current: Vout = I · R
For a divider, sensitivity (mV per °C) is highest when the fixed resistor roughly equals the sensor's resistance at your target temperature — the suggested value uses that rule. A parallel resistor across an NTC trades some sensitivity for a straighter response, shown on the graph as the "without Rp" comparison.
The ADC resolution figure is the temperature step per code (Vref ÷ 2^bits ÷ sensitivity) at the target — useful for checking whether a given ADC resolves finely enough.