Semtech Corporation

Lei Hua

Bo Liang

William Allen Russell

Changjun Huang

Pengcheng Han

A semiconductor device includes a voltage input circuit node and a ground voltage node. A first transistor is coupled between the voltage input circuit node and the ground voltage node. A triggering circuit is coupled between the voltage input circuit node and the ground voltage node in parallel with the first transistor. The triggering circuit includes a trigger diode. An output of the triggering circuit is coupled to a control terminal of the first transistor. A load is powered by coupling the load between the voltage input circuit node and the ground voltage node.

Protection circuit with a FET device coupled from a protected bus to ground

A switched mode power converter includes a transformer having a primary winding, a secondary winding, and a bias winding. A primary side power switch is coupled to the primary winding and is adapted to periodically apply an input voltage to the primary winding. An output filter is operatively coupled to the secondary winding to provide an output voltage and output current. A forward synchronous rectification device is operatively coupled in series between the secondary winding and the output filter. A free-wheeling synchronous rectification device is operatively coupled in shunt with the secondary winding and the output filter. A control circuit is coupled to the bias winding and the forward and free-wheeling synchronous rectification devices. The control circuit includes a forward driving device adapted to couple an activation terminal of the forward synchronous rectification device to a first end of the secondary winding and a free-wheeling driving device adapted to couple an activation terminal of the free-wheeling synchronous rectification device to a second end of the secondary winding. The control circuit activates the forward and free-wheeling driving devices responsive to voltage on the bias winding.

Switching mode power converter having secondary side bias generating and driving circuit to provide synchronous rectification and active clamp

A control circuit for a switched mode power converter is adapted to receive a current sense signal reflecting the output current of the power converter and a feedback signal reflecting the output voltage of the power converter. The control circuit includes a first over-current protection circuit adapted to shut off operation of the switched mode power converter if a sum of the current sense signal and the feedback signal exceed a first predetermined limit, and a second over-current protection circuit adapted to regulate operation of said primary side power switch responsive a comparison of the sum of the current sense signal and the feedback signal to a second predetermined limit. The second predetermined limit is less than the first predetermined limit.

Growing community of inventors

Camarillo, CA, United States of America

Lei Hua