Differential thermistor circuit
This document discusses, among other things, an apparatus and method for providing temperature information. In an example, an integrated circuit apparatus can include a first resistor configured to be coupled to a first terminal of a temperature-sensitive resistance, a second resistor configured to be coupled to a second terminal of the temperature-sensitive resistance, and a temperature information circuit configured to receive a first voltage from the first terminal of the temperature-sensitive resistance and a second voltage from the second terminal of the temperature-sensitive resistance. The temperature information circuit can provide the temperature information using the first and second voltages.
1. A method comprising:
receiving a first voltage from a first resistor coupled to a first terminal of a temperature-sensitive resistance at a temperature information circuit;
receiving a second voltage from a second resistor coupled to second terminal of the temperature-sensitive resistance at the temperature information circuit;
providing an output signal indicative of a difference between the first and second voltages; and
comparing the output signal to a reference voltage to provide an indication of temperature.
2. The method of claim 1 , wherein comparing the output signal to a reference voltage includes receiving the reference voltage from a reference resistor.
3. The method of claim 1 , wherein comparing the output signal to a reference voltage includes receiving the reference voltage from a reference diode.
4. The method of claim 1 , wherein a value of the first resistor substantially corresponds to a value of the second resistor.
5. The method of claim 1 , wherein the providing includes amplifying a difference between the first and second voltages using a differential amplifier of the temperature information circuit to provide temperature information.
6. The method of claim 1 , wherein the comparing includes comparing the output signal to a reference voltage using a comparator of the temperature information circuit to provide the indication of temperature.
7. The method of claim 1 , wherein the comparing the output signal to the reference voltage includes comparing an output signal of a differential amplifier of the temperature information circuit with the reference voltage.
8. The method of claim 7 , wherein comparing the output signal of a differential amplifier of the temperature information circuit to a reference voltage includes receiving the reference voltage from a reference resistor.
9. The method of claim 7 , wherein comparing the output signal of a differential amplifier of the temperature information circuit to a reference voltage includes receiving the reference voltage from a reference diode.
10. The method of claim 1 , including receiving the reference voltage from a reference generator of the temperature information circuit.
11. The method of claim 10 , wherein the reference generator includes a band-gap reference circuit.
12. The method of claim 10 , wherein the reference generator includes a diode based reference circuit.
13. The method of claim 10 , wherein the receiving the reference voltage includes applying a voltage across a voltage divider to provide the reference voltage.
14. The method of claim 13 , wherein applying the voltage includes applying the voltage across a voltage divider including an external resistance.
15. The method of claim 13 , wherein the applying the voltage includes applying the voltage across a voltage divider including a programmable resistance to provide a programmable reference voltage.