How does the “body diode” forward drop change if the gate is driven to a negative voltage?
The “body diode” drop for the eGaN Device is the typical Gate Threshold Voltage. A negative voltage applied to the gate will add to the “Vf” drop of the diode – hence applying a negative gate voltage is NOT recommended if you plan to use the reverse conduction characteristic.
Unlike silicon MOSFETs, there is no need to wait for the usual dead time. In other words, since the switch turns off in less than 10 ns (typical), there is no need to wait for 40-60 ns for the other device in the same leg to shut off before turning on the channel. As with any synchronous FET application, the diode conduction needs to be kept to the minimum. Please see white paper Dead-Time Optimization for Maximum Efficiency