An automotive drive system for a high voltage electric motor comprises a microcontroller and ECU powered by a low voltage (12 volt) bus net which controls the drives of a high voltage inverter powered by a 100 volt or higher source, which, in turn, drives the motor. To provide good electrical insulation between the low voltage and high voltage systems, the low voltage control signals are produced by a low voltage signal input chip which has a bottom electrode which produces a control potential responsive to the ECU output and a high voltage driver IC which drives the power devices of the high voltage inverter. The high voltage driver IC has a top electrode which drives the high voltage IC function. The bottom electrode of the LV input chip is coupled to the top electrode of the high voltage driver IC through an insulation layer, defining a capacitive coupler which defines an isolation barrier between the low voltage net and the high voltage system insulation. The two ICs may be bare chips, individually packaged chips or co-packed chips. Plural control IC chips and driver IC chips can communicate with one another for diverse control functions, including “smart” functions.