Title:
SWITCHING POWER SUPPLY AND SYNCHRONOUS RECTIFICATION CONTROL CIRCUIT
Document Type and Number:
Japanese Patent JP2023021706
Kind Code:
A
Abstract:
To provide a switching power supply capable of protecting input terminals of an IC of the synchronous rectification control circuit against a negative surge of a secondary transformer, and the synchronous rectification control circuit.SOLUTION: A resistance RDET is provided between one end T21 of a secondary transformer T2 and a detection terminal DET of a synchronous rectification circuit 5. The emitter of a bipolar transistor Q1 is connected to the detection terminal DET. A current mirror circuit 52 detects a current IRDET flowing from the emitter of the bipolar transistor Q1 to the resistance RDET. A comparison circuit 53 compares the current IRDET detected by the current mirror circuit 52 with a first current (I1+I2) or a second current I1, and performs ON/OFF control over a power MOS transistor MPW2.SELECTED DRAWING: Figure 2
Inventors:
MIZOE KIMIYOSHI
Application Number:
JP2021126745A
Publication Date:
February 14, 2023
Filing Date:
August 02, 2021
Export Citation:
Assignee:
NISSHINBO MICRO DEVICES INC
International Classes:
H02M3/28
Attorney, Agent or Firm:
Patent Attorney Corporation Eiko Office