This post explains for the IGBT.
The Part Number is G4PF50W, IRG4PF50W.
The function of this semiconductor is 900V, 51A, IGBT.
Manufacturer: International Rectifier
Image and Pinout
Features
1. Optimized for use in Welding and Switch-Mode Power Supply applications
2. Industry benchmark switching losses improve efficiency of all power supply topologies
3. 50% reduction of Eoff parameter
4. Low IGBT conduction losses
5. Latest technology IGBT design offers tighter parameter distribution coupled with exceptional reliability
Benefits :
1. Lower switching losses allow more cost-effective operation and hence efficient replacement of larger-die MOSFETs up to 100kHz
2. Of particular benefit in single-ended converters and Power Supplies 150W and higher
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Absolute Maximum Ratings :
1. Collector to emitter voltage: Vces = 900 V
2. Gate to emitter voltage: Vges = ± 20 V
3. Collector current : Ic = 51 A
4. Collector dissipation : Pc = 200 W
5. Junction temperature : Tj = 150 °C
6. Storage temperature: Tstg = -55 to +150 °C