System and method to soft-start synchronous buck converters

摘要

A system includes a feedback module that communicates with a capacitor connected across an output of a power converter and that generates a feedback voltage indicating a pre-bias voltage across the capacitor before power is supplied to the power converter. A comparator compares the feedback voltage to a reference voltage and determines whether the pre-bias voltage across the capacitor is greater or less than a desired output voltage of the power converter when power is supplied to the power converter. A ramp generator module generates a first or second ramp if the pre-bias voltage is less or greater than the desired output voltage. A control module drives high-side and low-side switches to charge or discharge the capacitor from the pre-bias voltage to the desired output voltage based on the first or second ramp and controls the power converter after a voltage across the capacitor reaches the desired output voltage.