Resistive thermometer excitation and calibration

An integrated circuit, comprising:

• an excitation current source;
• a first resistive temperature sensor;
• a second resistive temperature sensor;
• measurement switching circuitry;
• an analog-to-digital converter (ADC) circuit;
• and
• a control circuit, the control circuit configured to:
• using the measurement switching circuitry, route an excitation current from the excitation current source through the first resistive temperature sensor to establish a first sensor signal and, contemporaneously, route the excitation current through the second resistive temperature sensor to establish a second sensor signal;
• using the measurement switching circuitry, deliver the first sensor signal to a first input of the ADC circuit;
• using the measurement switching circuitry, deliver the second sensor signal to a second input of the ADC circuit;
• and
• generate a digital representation of a relative indication of the first sensor signal with respect to the second sensor signal using the ADC circuit;
• wherein the first resistive temperature sensor and second resistive temperature sensors are monolithically co-integrated on or within a commonly shared substrate of the integrated circuit, the second resistive temperature sensor having a temperature that is different from the first resistive temperature sensor.

An integrated circuit, comprising:

• an excitation current source;
• a first resistive temperature sensor;
• a second resistive temperature sensor;
• measurement switching circuitry;
• an analog-to-digital converter (ADC) circuit;
• and
• a control circuit, the control circuit configured to determine a measured temperature value corresponding to the first resistive temperature sensor using:
• digital representations of respective voltages established contemporaneously across the first resistive temperature sensor and the second resistive temperature sensor in response to an excitation current provided by the excitation current source, the digital representations obtained using the ADC circuit;
• and
• calibration data indicative of a ratio of resistance values of the first resistive temperature sensor and the second resistive temperature sensor, and at least first-order temperature coefficients of resistance corresponding to the first resistive temperature sensor and the second resistive temperature sensor, respectively.