Patent attributes
In described examples, a method of determining whether there is an open load fault in a test circuit includes closing a first switch to couple an input voltage to a first LC filter in which a first capacitor is coupled to a ground, the first LC filter coupled to a first terminal coupled to the test circuit; and closing a second switch to couple the input voltage to a second LC filter in which a second capacitor is coupled to the ground, the second LC filter coupled to a second terminal coupled to the test circuit. After the LC filters charge to the input voltage, the second switch is opened, and the second capacitor is discharged across a discharge resistor for a specified discharge time. The voltage across the discharge resistor falling below a reference voltage indicates that there is an open load fault in the test circuit.
