US Patent No. 10,172,197

DIMMABLE SINGLE-STAGE POWER CONVERTER WITH ADAPTIVE SWITCHING FREQUENCY CONTROL


Patent No. 10,172,197
Issue Date January 01, 2019
Title Dimmable Single-stage Power Converter With Adaptive Switching Frequency Control
Inventorship Xiaolin Gao, Campbell, CA (US)
Zhiqiu Ye, Beijing (CN)
Nailong Wang, Beijing (CN)
Assignee DIALOG SEMICONDUCTOR, INC., Campbell, CA (US) DIALOG SEMICONDUCTOR (UK) LI...

Claim of US Patent No. 10,172,197

1. A method for a circuit with adaptive switching frequency control, the method comprising:operating a controller of a dimmable single-stage power converter in pulse width modulation (PWM) mode at a first switching frequency level from a maximum dimming duty-ratio level until a first dimming duty-ratio level;
operating the controller in PWM mode, while reducing switching frequency from the first switching frequency level to a second switching frequency level, from the first dimming duty-ratio level until a second dimming duty-ratio level;
operating the controller in PWM mode at the second switching frequency level from the second dimming duty-ratio level until a current command (Vipk) falls below a predetermined low limit value; and
operating the controller in skip mode, while reducing the switching frequency from the second switching frequency level, until a minimum dimming duty-ratio level is reached.