A digital audio driver having a floating PWM input and for controlling a stage of high voltage, high speed high- and low-side MOSFETs series connected at a node. The driver includes a floating input interface circuit having a protection circuit to provide secure protection sequence against over-current conditions; and high and low side circuits for driving the high- and low-side MOSFETs, each high and low side circuit including a bi-directional current sensing circuit which requires no external shunt resistors that enables capture of over-current conditions at either positive or negative load current direction. The RDS(ON) of the high- and low-side MOSFETs is used as current sensing resistors, once the RDS(ON) exceeds a pre-determined threshold, an over current output signal is fed to the protection block to shutdown the MOSFET to protect the devices.