Self-calibrated dc-dc converter

A system, comprising:

• a power source;
• a load;
• a gate driver having multiple inputs and multiple outputs;
• a power converter, comprising:
• a first transistor having a gate terminal coupled to one of the gate driver outputs, a first terminal coupled to the power source, and a second terminal;
• and
• an energy storage element having a first terminal coupled to the second terminal of the first transistor and a second terminal coupled to the load;
• and
• a first comparator having a first input coupled to the power converter, a second input, and an output coupled to one of the gate driver inputs;
• a controller, comprising:
• a calibration loop having an input coupled to one of the gate driver outputs and an output;
• and
• an on-time (TON) generator having an input coupled to the output of the calibration loop and an output coupled to the output of the first comparator,
• wherein the TON generator is configured to generate TON for controlling the gate driver to control the power converter via the gate terminal of the first transistor, and
• wherein the calibration loop is configured to:
• compare a frequency of a signal provided by the gate driver to the first transistor to a frequency of a reference clock;
• modify a value of a counter based on a result of the comparison of the frequency of the signal provided by the gate driver to the first transistor to the frequency of the reference clock;
• and
• control the TON generator to modify an amount of capacitance present in a timing circuit of the TON generator based on the value of the counter.

A method, comprising:

• generating an on-time (TON);
• controlling a power converter at least partially according to the generated TON;
• generating a switching frequency signal having a frequency approximately equal to at least one control signal provided to the power converter to control the power converter;
• converting the switching frequency signal to a first signal having a voltage representative of the frequency of the switching frequency signal;
• converting a reference clock to a second signal having a voltage representative of a frequency of the reference clock;
• biasing the first and second signals;
• comparing the biased first and second signals;
• modifying an output value of a counter based on a result of the comparison;
• and
• modifying an amount of capacitance in a timer of a TON generator that generates TON to modify the frequency of the switching frequency signal based on the output value of the counter.