Dialog Semiconductor Gmbh

Hanguang Zhang

Pengju Kong

Hien Huu Bui

Tao Li

Wenbo Liang

A synchronous rectifier controller method is provided for controlling the on and off periods of a synchronous rectifier (SR) switch transistor in a switching power converter. The method includes a first step of monitoring an unfiltered to control whether the SR switch transistor is turned on during a first part of a power switch cycle. The method also includes a second step of monitoring a filtered SR switch signal to control whether the SR switch is turned on during a remaining second part of the power switch cycle.

Adaptive synchronous rectifier sensing deglitch

A synchronous rectifier controller for controlling the on and off periods of a synchronous rectifier switch transistor in a switching power converter. In particular, the synchronous rectifier controller is configured to adaptively enable and disable a deglitch filter for filtering a turn-on signal for the synchronous rectifier switch transistor. In this fashion, the synchronous rectifier switch transistor may be switched on more rapidly during periods when the deglitch filter is disabled for greater efficiency yet the switching power converter is protected by the deglitch filter when it is not disabled.

A switching power converter may include a power switch coupled to a primary winding of a transformer, and a primary controller configured to turn on and off the power switch, a synchronous rectifier switch coupled to a secondary winding of a transformer, and a synchronous rectifier controller configured to turn on and off the synchronous rectifier switch. The synchronous rectifier controller may monitor a voltage across the synchronous rectifier switch. The synchronous rectifier controller may determine a period of a resonant oscillation of the voltage across the synchronous rectifier switch following at least one cycling off of the synchronous rectifier switch. The synchronous rectifier controller may adjust the minimum off-time period for the synchronous rectifier switch based on the period of the resonant oscillation. The synchronous rectifier controller may adaptively adjust a minimum off-time period for the synchronous rectifier switch.

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Campbell, CA, United States of America

Hanguang Zhang