US 12,456,914 B2
Control device
Ke-Horng Chen, Hsinchu (TW); Ying-Feng Wu, Hsinchu (TW); Yu-Chou Ko, Hsinchu (TW); Kuo-Lin Zheng, Hsinchu (TW); and Ke-Ming Su, Hsinchu (TW)
Assigned to Chip-GaN Power Semiconductor Corporation, Hsinchu (TW)
Filed by CHIP-GAN POWER SEMICONDUCTOR CORPORATION, Hsinchu (TW)
Filed on Oct. 24, 2023, as Appl. No. 18/492,976.
Claims priority of application No. 112128991 (TW), filed on Aug. 2, 2023.
Prior Publication US 2025/0047189 A1, Feb. 6, 2025
Int. Cl. H02M 1/08 (2006.01); H02M 1/00 (2006.01); H02M 3/335 (2006.01)
CPC H02M 1/08 (2013.01) [H02M 1/0012 (2021.05); H02M 3/33592 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A control device coupled to a control terminal of a primary-side switch, the primary-side switch coupled to a primary side of a first transformer in series, and the control device comprising:
a first capacitor;
a drive controller coupled to the control terminal of the primary-side switch;
a constant current source coupled to the first capacitor and configured to generate a constant current;
a discharge-controlled current source coupled to the constant current source and the first capacitor;
a current mirror coupled to a node between the first capacitor and the primary side of the primary-side switch and configured to generate a copy current based on a node voltage of the node, wherein the copy current is configured to charge the first capacitor to generate a copy voltage across the first capacitor;
a sample-and-hold circuit coupled to the drive controller, the discharge-controlled current source, and the current mirror, wherein when the drive controller turns on the primary-side switch, the sample-and-hold circuit drives the discharge-controlled current source to sample and hold a control current from the constant current and the copy current; and
a comparison circuit coupled to the drive controller, the sample-and-hold circuit, the node, and the first capacitor and coupled to the node voltage and the copy voltage, wherein when the node voltage is higher than the copy voltage, the comparison circuit drives the drive controller to turn off the primary-side switch.