View irf840b datasheet:

November 2001 IRF840B/IRFS840B 500V N-Channel MOSFET General Description Features These N-Channel enhancement mode power field effect • 8.0A, 500V, RDS(on) = 0.8? @VGS = 10 V transistors are produced using Fairchild’s proprietary, • Low gate charge ( typical 41 nC) planar, DMOS technology. • Low Crss ( typical 35 pF) This advanced technology has been especially tailored to • Fast switching minimize on-state resistance, provide superior switching • 100% avalanche tested performance, and withstand high energy pulse in the • Improved dv/dt capability avalanche and commutation mode. These devices are well suited for high efficiency switch mode power supplies, power factor correction and electronic lamp ballasts based on half bridge. D G TO-220 TO-220F G D S G D S IRF S