DETECTING OPEN CONNECTION OF AUXILIARY WINDING IN A SWITCHING MODE POWER SUPPLY

摘要

A power converter has a transformer including a primary winding coupled to an input voltage, a secondary winding coupled to an output of the power converter, and an auxiliary winding is configured to detect an open connection fault of the auxiliary winding. The power converter includes a current source coupled to the auxiliary winding that, when activated, supplies a current to the auxiliary winding. A controller measures a voltage across the auxiliary winding. Responsive to detecting an increase in the voltage across the auxiliary winding while the current source is activated, the controller disables the power converter.

主权项

1. A power converter comprising:
a transformer including a primary winding coupled to an input voltage, a secondary winding coupled to an output of the power converter, and an auxiliary winding, output voltage of the power converter being reflected as feedback across the auxiliary winding; a current source coupled to the auxiliary winding, the current source when activated supplying a current to the auxiliary winding; and a controller regulating the output voltage of the power converter based on the feedback across the auxiliary winding, the controller adapted to measure a voltage across the auxiliary winding while the current source is activated and disable the power converter responsive to detecting the voltage across the auxiliary winding is greater than a threshold voltage while the current source is activated.