Current share in multiphase SMPCs by digital filtering

This paper introduces a new method of passive current balancing for digital control based upon the duty-cycle matching principle. The method does not rely on a current balancing loop and therefore the stability and performance concerns associated with the traditional current balance loop are obviated. Being sensorless, it is insensitive to current measurement inaccuracies caused by noise, component value tolerance or variation. It will be shown that effective current balancing can be achieved via some simple modifications to standard voltage mode control laws, allowing current balancing to be achieved with minor additional complexity.