Patent ID: 9742299
Date: 2017-08-22
CPC Classifications: H02M,Y02B

Claim:
1. A synchronous rectification controller that is arranged on a secondary side of an insulated synchronous rectification DC/DC converter, and that controls a synchronous rectification transistor, the synchronous rectification controller comprising: a pulse generator that generates a pulse signal configured as an instruction to switch on and off the synchronous rectification transistor based on at least a voltage across the synchronous rectification transistor; a driver that switches on and off the synchronous rectification transistor according to the pulse signal; and an automatic shutdown circuit that judges, based on the voltage across the synchronous rectification transistor, whether a primary-side controller that controls a switching transistor at a primary side of the DC/DC converter is operating in a burst mode or a non-burst mode, and that instructs the driver to suspend switching of the synchronous rectification transistor when judgment is made that an operation mode of the primary-side controller is the burst mode, wherein, when a predetermined first time period continues in a state in which the pulse signal is not generated, the automatic shutdown circuit judges that the operation mode is the burst mode.