Multiphase power regulator with active transient response circuitry

A multiphase power regulator comprising:

• a multiphase pulse width modulator;
• an output stage comprising a high side transistor, a low side transistor and an inductor, the output stage configured to supply power to a load responsive to signals generated by the multiphase pulse width modulator;
• an active transient response circuit coupled between the output stage and the multiphase pulse width modulator and configured to detect the voltage level at the output stage and provide a signal to the multiphase pulse width modulator that is a function of the amplitude of the deviation of the detected voltage level from a target voltage;
• an additional active transient response circuit coupled to the load and configured to provide an additional current path to compensate for a transient event at the load;
• an additional high side transistor coupled to the load;
• an additional low side transistor coupled to the load;
• and
• a calibration control circuit coupled to the additional low side transistor and configured to control operation of the additional low side transistor during initialization of the multiphase power regulator, the calibration control circuit being off during normal operation of the multiphase power regulator,
• wherein the additional active transient response circuit is coupled to the additional transistors and further configured to turn on the additional low side transistor responsive to the voltage at the load increasing above a specified voltage and turn on the additional high side transistor responsive to the voltage at the load decreasing below a specified voltage.