A driving circuit to control/drive a contactor using a high-side driver integrated into the battery pack controller. The driver circuit may electrically isolate the controller pins of the battery pack controller (which interface the contactors) from the low-voltage digital processing core of the battery pack controller. The driver circuit may provide techniques to diagnose a fault by monitoring the voltage at the output of the driver as compared to the reference voltage. The driver circuit may include an electronic switch, such as a field-effect transistor, that is configured on the high side of the contactor to control voltage from an energy source to the contactor.