METHOD AND APPARATUS FOR TESTING AND PROTECTING DIGITAL OUTPUT CIRCUITS

A method and system for testing and protecting the operability of an output module. An output channel includes a transistor having a gate, a source, and a drain. The output channel drives a load with a load voltage and a load current in dependence upon a gate drive signal applied to the gate. The system determines a voltage threshold and a current threshold and monotonically varies the gate drive signal from a starting value for a predetermined time interval while monitoring the load current and the load voltage. The system returns the gate drive signal to the starting value if any of the load voltage reaches the voltage threshold, the load current reaches the current threshold, or a predetermined time interval expires indicating the condition of the output module.