Microchip Technology Incorporated
METHOD AND APPARATUS FOR PHASE CURRENT BALANCING IN A MULTI-PHASE DC-TO-DC CONVERTER

Abstract:

A multi-phase DC-to-DC controller is provided. The controller includes a plurality of current sense circuits that sense current in respective converter cell of the converter, and generate respective current sense signals, an averaging circuit that receives the respective current sense signals and generates an average signal, a plurality of error detector circuits that compare respective current sense signals with the average signal and generate respective voltage imbalance signals, a plurality of transconductor circuits that convert respective voltage imbalance signals to respective current imbalance signals, and a plurality of pulse width modulation (PWM) generators that output PWM signals to control respective converter cells based on a comparison between a ramp threshold voltage of the PWM generators and a PWM ramp voltage that is based on the sum of one of the respective current imbalance signals and a first current that is proportional to the input voltage.