05282107 is referenced by 58 patents and cites 3 patents.

An embodiment of the present invention is a switching power supply that includes a full-wave bridge rectifier to rectify incoming AC line voltage, a transformer having a primary winding and two secondary windings and a switched mode power supply chip that includes an integrated high voltage power MOSFET with a low voltage tap in the drift region. The MOSFET controls power switching of the primary winding of the transformer and has a high voltage present during initial power-up. This high voltage is dropped across the JFET part of the MOSFET and supplies a safe operating area protection circuit with a low voltage signal that will shut-off the MOSFET if the current passing through the MOSFET produces a voltage drop at the tap that exceeds a predetermined maximum.

Title
Power MOSFET safe operating area current limiting device
Application Number
7/938705
Publication Number
5282107
Application Date
September 1, 1992
Publication Date
January 25, 1994
Inventor
Balu Balakrishnan
Saratoga
CA, US
Agent
Thomas E Schatzel
Assignee
Power Integrations
CA, US
IPC
H02H 7/122
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