Voltage regulator with optimal efficiency selection and a master-slave zero cross detection configuration

摘要

A voltage regulator includes a first phase power stage, a second phase power stage, and a controller. The first phase power stage includes a zero cross detection circuit configured to measure a current level for the first phase power stage, and to cause a diode emulation state in the first phase power stage when the current level is substantially equal to zero. The second phase power stage is in communication with the zero cross detection circuit, and configured to enter the diode emulation state in response to receiving a signal from the zero cross detection circuit. The controller is coupled to the first phase power stage and to the second phase power stage. The controller is configured to measure an output current of the voltage regulator and to activate the second phase power stage when the output current is above a first threshold current level.

主权项

1. A voltage regulator comprising:
a first phase power stage connected in parallel with a second phase power stage, the first phase power stage including:
a first high side transistor configured to activate and deactivate to regulate an input voltage; anda first low side transistor coupled to the first high side transistor, the first low side transistor configured to deactivate in response to a signal from a zero cross detection circuit of the second phase power stage, wherein the signal indicates that a current level in the second phase power stage is substantially equal to zero; wherein the first phase power stage is configured to be activated in response to an output current being above a first threshold current level.