With　the　increase　of　switching　frequency　to　tens　of　MHz,　the　synchronous　rectification　faces　many　new　challenges,　among　which　a　significant　one　is　the　design　of　the　driver　circuit　for　the　synchronous　rectification　with　wide　bandgap　gallium　nitride　(GaN)　devices.　According　to　the　self-resonant　driving　theory,　an　in-phase　feedback　synchronous　rectification　driver　circuit　(SRDC)　based　on　GaN　devices　and　the　driver　chip　is　proposed　in　this　paper.　In　this　SRDC,　the　nonlinear　parasitic　capacitors　are　replaced　with　external　capacitors,　and　the　synchronous　driving　signal　is　in-phase　with　the　excitation　source.　The　new　scheme　can　provide　precise　driving　timing,　stable　driving　amplitude　and　flexible　phase-shifting　characteristics　for　the　synchronous　rectification　of　a　high-frequency　DC-DC　resonant　converter　(HFDRC)　based　on　GaN　devices.　In　this　paper,　a　detailed　parameter　design　method　is　introduced　by　analyzing　the　characteristics　of　the　feedback　network.　The　feasibility　and　effectiveness　of　the　proposed　SRDC　are　verified　on　a　20　MHz　prototype　with　18　V　input　and　5　V/2　A　output.　©　2013　IEEE.