A power converter includes multiple phase circuits, each phase circuit
includes a power switch for delivering power to an output of the power
converter, a current sensor connected to the power switch for sensing a
current in the power switch, a duty cycle controller having an output
connected to the current sensor, and a low pass filter connected to the
current sensor. The low pass filter is configured to produce a
substantially direct current signal proportional to the average current
in the power switch. Further, the duty cycle controller is configured to
receive the direct current signal and control a duty cycle of the power
switch in response to the direct current signal thereby balancing the
currents in the phase circuits.