US 11,817,790 B2
High-side synchronous rectifier driver with reduced controller power supply charging efficiency and reduced EMI
Guang Feng, Campbell, CA (US); Pengju Kong, Campbell, CA (US); Xiyuan Liu, Campbell, CA (US); and Qingqing Zong, Campbell, CA (US)
Assigned to Dialog Semiconductor Inc., Campbell, CA (US)
Filed by DIALOG SEMICONDUCTOR INC., Campbell, CA (US)
Filed on Jul. 14, 2021, as Appl. No. 17/375,954.
Prior Publication US 2023/0016802 A1, Jan. 19, 2023
Int. Cl. H02M 3/335 (2006.01); H02M 1/44 (2007.01)
CPC H02M 3/33592 (2013.01) [H02M 1/44 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A controller for a flyback converter with a high-side synchronous rectifier switch transistor, comprising:
an auxiliary capacitor;
a power supply capacitor for storing a power supply voltage for the controller; and
a plurality of switches having a first switching state in which the auxiliary capacitor is coupled to a charge source and the power supply capacitor is isolated from the auxiliary capacitor and having a second switching state in which the auxiliary capacitor is isolated from the charge source and coupled to charge the power supply capacitor.