Temperature detection of a power switch based on paired measurements of current and voltage
This disclosure is directed to circuits and techniques for detecting or responding to temperature of a power switch based on paired measurements of current and voltage. A driver circuit for a power switch may be configured to perform a current measurement and a voltage measurement associated with a temperature-dependent circuit element and control the power switch based at least in part on the current measurement and the voltage measurement. In some examples, the current and voltage measurements may be used to determine the temperature of the power switch.
1. A circuit comprising a driver circuit configured to control a power switch circuit that includes a power switch and a temperature-dependent circuit element electrically coupled to at least one node of the power switch:
wherein the driver circuit is configured to deliver a modulation signal to a control node of the power switch to control on/off switching of the power switch,
wherein the driver circuit is configured to perform a current measurement and a voltage measurement associated with the temperature-dependent circuit element and control the power switch based at least in part on the current measurement and the voltage measurement, and
wherein the current measurement and the voltage measurement are performed based on timing associated with the on/off switching of the power switch.
2. The circuit of claim 1 , wherein the current measurement and the voltage measurement are performed at a time when a voltage over the power switch is stable and the power switch is not in a transition state.
3. The circuit of claim 2 , wherein the current measurement and the voltage measurement are performed at a time when the power switch is turned on.
4. The circuit of claim 2 , wherein the current measurement and the voltage measurement are performed at a time when the power switch is turned off, and wherein the driver circuit is configured to apply a negative voltage to the control node during the current measurement and the voltage measurement.
5. The circuit of claim 1 , wherein the current measurement and the voltage measurement are paired measurements.
6. The circuit of claim 1 , wherein the driver circuit includes logic configured to control the power switch in response to the current measurement and the voltage measurement indicating a temperature of the power switch.
7. The circuit of claim 6 , wherein the logic is configured to adjust transition speed of the power switch in response to the current measurement and the voltage measurement indicating the temperature of the power switch.
8. The circuit of claim 6 , wherein the logic is configured to disable the power switch in response to the current measurement and the voltage measurement indicating the temperature of the power switch.
9. The circuit of claim 6 , wherein the logic is configured to control the power switch in response to a calculation of impedance indicating the temperature of the power switch, wherein the calculation of the impedance is based on the current measurement and the voltage measurement.
10. The circuit of claim 1 , wherein the driver circuit includes a temperature unit configured to determine a temperature of the power switch based on the current measurement and the voltage measurement.
11. The circuit of claim 10 , wherein the circuit further comprises a control unit configured to adjust the modulation signal based on the determined temperature.
12. The circuit of claim 1 , wherein the driver circuit is configured to perform the current measurement and the voltage measurement within a same switching period of the power switch.
13. The circuit of claim 1 , wherein the driver circuit is configured to perform at least one of the current measurement or the voltage measurement a plurality of times within each switching period of the power switch.
14. The circuit of claim 1 , wherein the driver circuit is configured to perform at least one current measurement and a plurality of voltage measurements within a same switching period of the power switch.
15. A method of controlling a power switch circuit including a power switch and a temperature-dependent circuit element electrically coupled to at least one node of the power switch, the method comprising:
delivering a modulation signal to a control node of the power switch to control on/off switching of the power switch;
performing a current measurement associated with the temperature-dependent circuit element;
performing a voltage measurement associated with the temperature-dependent circuit element, wherein performing the current measurement and performing the voltage measurement comprises performing the current measurement and the voltage measurement according to a timing sequence that is based on timing associated with the on/off switching of the power switch; and
controlling the power switch based at least in part on the current measurement and the voltage measurement.
16. The method of claim 15 , wherein controlling the power switch comprises:
controlling the power switch circuit in response to the current measurement and the voltage measurement indicating a temperature of the power switch.
17. The method of claim 15 , further comprising:
calculating an impedance based on the current measurement and the voltage measurement and controlling the power switch based on the calculated impedance.
18. The method of claim 15 , further comprising:
determining a temperature of the power switch based on the current measurement and the voltage measurement,
wherein controlling the power switch comprises adjusting the modulation signal via a controller based on the determined temperature.
19. The method of claim 15 , wherein performing the current measurement and the voltage measurement comprises:
performing the current measurement and the voltage measurement in a paired manner.
20. The method of claim 19 , wherein performing the current measurement and the voltage measurement in the paired manner comprises performing the current measurement and the voltage measurement within a same switching period of the power switch.
21. A circuit arrangement comprising:
a power switch circuit including a power switch and a temperature-dependent circuit element electrically coupled to at least one node of the power switch; and
a driver circuit configured to deliver a modulation signal to a control node of the power switch to control on/off switching of the power switch, wherein the driver circuit is configured to perform a current measurement and a voltage measurement associated with the temperature-dependent circuit element and control the power switch based at least in part on the current measurement and the voltage measurement, and
wherein the current measurement and the voltage measurement are performed based on timing associated with the on/off switching of the power switch.