Abstract: An electronic thermometer is particularly adapted for use as a fever thermometer and employs a unique temperature sensor configuration comprising a platinum temperature sensing resistor and tantalum nitride reference resistor both mounted on the same substrate. The resistors are selectively coupled to the input of a dual ramp integrator forming part of an analog to digital converter. Digital control circuitry causes the sensing resistor to be coupled to the input of the integrator during a first mode and causes the reference resistor to be coupled to the input during a second mode. Included in the digital circuitry is a first sensor memory and a second reference memory. These memories have stored therein a digital number indicative of the response of both resistors at a predetermined temperature obtained during initial calibration of the sensor and thermometer. The stored values are compared during the respective mode with the accumulated count in a clock counting circuit.