Patent ID: 11870350
Assignee: APPULSE POWER INC.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A switched-mode power converter, comprising:
a main-switch; and
a controller circuit configured in a first mode of startup operation to generate a fixed switching frequency pulse width modulation (PWM) signal with an incrementing duty-ratio value to control the main-switch;
wherein, based on a first comparison of a power converter output voltage with a reference voltage, the controller circuit is configured to switch to a second mode of startup operation during which the controller circuit decreases an off-time of the duty-ratio value;
wherein the second mode of startup operation is a quasi-resonant valley reduction mode of operation in which the controller circuit reduces a number of quasi-resonant valleys detected in one or more off-times of the main-switch in one or more respective main-switch switching periods; and
wherein the controller circuit is configured to enter a normal mode of operation based on a second comparison that determines that a difference between the reference voltage and an indication of the power converter output voltage is not greater than a predefined threshold voltage.