Converters based on dual active bridge (DAB) topology are becoming more popular with its high-power density and possibility of bi-directional power flow. Popular applications include renewable energy storage and conversion and electric vehicle charging, but it could also be used for electric transport of lower power rating, like electric scooters and bicycles. The advances in wide band-gap (WBG) semiconductor technology, such as gallium nitride (GaN) high-electron mobility transistors (HEMTs), have prompted the use of these transistors which have lower conduction losses and work with higher switching frequencies. As lower driving voltage is required for such transistors, and previously used driver IC are not directly compatible, EZDrive circuit is implemented. Calculations for such losses are well established, but as GaN HEMT have smaller parasitic capacitances, the latest transistor switching transients do not fully match with the existing model’s Miller effect. In this paper the regular MOSFET switching loss calculation is compared with the updated GaN HEMT switching loss results. A 300W GaN based DAB prototype with GaN Systems' proposed “EZDrive” was built to test the calculations and the driving circuits impact.