View stp4nk50z datasheet:

STP4NK50Z - STP4NK50ZFP STD4NK50Z - STD4NK50Z-1 N-CHANNEL 500V - 2.4? - 3A TO-220/TO-220FP/DPAK/IPAK Zener-Protected SuperMESH™Power MOSFET TYPE VDSS RDS(on) ID Pw STP4NK50Z 500 V < 2.7 ? 3 A 45 W STP4NK50ZFP 500 V < 2.7 ? 3 A 20 W STD4NK50Z 500 V < 2.7 ? 3 A 45 W STD4NK50Z-1 500 V < 2.7 ? 3 A 45 W 3 TYPICAL RDS(on) = 2.3 ? 2 1 EXTREMELY HIGH dv/dt CAPABILITY TO-220 TO-220FP 100% AVALANCHE TESTED GATE CHARGE MINIMIZED VERY LOW INTRINSIC CAPACITANCES 3 VERY GOOD MANUFACTURING 3 2 1 REPEATIBILITY 1 IPAK DPAK DESCRIPTION The SuperMESH™ series is obtained through an extreme optimization of ST’s well established strip- INTERNAL SCHEMATIC DIAGRAM based PowerMESH™ layout. In addition to pushing on-resistance significantly down, special care is tak- en to ensu