Methods and apparatus for calibration of power converters
Methods and apparatus for a power regulator according to various aspects of the present invention may comprise a sensor adapted to generate a measurement of a voltage or a current. A memory may store a correction parameter that corresponds to the measurement, and a correction system may be adapted to adjust the measurement according to the correction parameter.
1. A method of operating a regulator, comprising:
measuring at least one of a voltage and a current of the regulator;
retrieving from a memory a correction parameter that compensates for errors or variations affecting the measurement;
adjusting the measurement according to the correction parameter; and
regulating an output of the regulator according to the adjusted measurement,
wherein regulating the output of the regulator according to the adjusted measurement comprises:
providing the adjusted measurement to a PWM (pulse width modulation) circuit; and
adjusting a duty cycle of a power stage of the regulator via the PWM circuit responsive to the adjusted measurement.
2. A method of operating a regulator according to claim 1 , wherein measuring the at least one of the voltage and the current of the regulator comprises measuring the current output of the regulator in conjunction with a current sensor exhibiting an error, and wherein the correction parameter compensates for the error of the current sensor.
3. A method of operating a regulator according to claim 1 , further comprising determining an output mode of the regulator.
4. A method of operating a regulator according to claim 3 , wherein the correction parameter retrieved from the memory also corresponds to the output mode of the regulator.
5. A method of operating a regulator according to claim 4 , wherein adjusting the measurement according to the correction parameter comprises offsetting a measured voltage by a voltage offset.
6. A method of operating a regulator according to claim 4 , wherein adjusting the measurement according to the correction parameter comprises offsetting a measured current in a first phase by a first current sense offset.
7. A method of operating a regulator according to claim 6 , wherein adjusting the measurement according to the correction parameter comprises offsetting a measured current in a second phase by a second current sense offset.
8. A method of operating a regulator according to claim 4 , wherein adjusting the measurement according to the correction parameter comprises offsetting a measured current by a gain adjustment for the output mode of the regulator.
9. A method of operating a regulator according to claim 4 , wherein adjusting the measurement according to the correction parameter comprises offsetting at least one of a measured voltage and a measured current by a value in a lookup table comprising a plurality of non-linear corrections.
10. A method of operating a regulator according to claim 1 , wherein the current of the regulator is measured and the correction parameter retrieved from the memory minimizes a current sense error associated with measuring the current of the regulator.
11. A method of operating a regulator according to claim 1 , wherein the correction parameter allows a current sense accuracy of the regulator to be improved beyond an accuracy of individual current sense elements and circuitry used to measure the current of the regulator.