In this work, we developed a compact single-chip isolated gate driver with a high isolation voltage that requires no additional isolated voltage source. This developed gate driver employed “Drive-By-Microwave Technology,” which supplies an isolated signal and power by mixture to a power switching device by using wireless power transmission technology. It was also developed that a new compact butterfly-shaped electro-magnetic resonant coupler (EMRC) that can be integrated in the GaN HFETs gate driver chip. The fabricated single-chip isolated gate driver demonstrated the isolated direct driving of a GaN-GIT power switching device.