This post explains for the Power Switch.
The Part Number is 1H0265R, KA1H0265R.
The function of this semiconductor is Fairchild Power Switch.
The package is TO-220F-4L Type
Manufacturer: Fairchild Semiconductor
Preview images :
The Fairchild Power Switch(FPS) product family is specially designed for an off line SMPS with minimal external components. The Fairchild Power Switch(FPS) consist of high voltage power SenseFET and current mode PWM controller IC. PWM controller features integrated fixed oscillator, under voltage lock out, leading edge blanking, optimized gate turn-on/turn-off driver, thermal shut down protection, over voltage protection, temperature compensated precision current sources for loop compensation and fault protection circuit. […]
1. Precision Fixed Operating Frequency
2. KA1M0265R (70kHz) , KA1H0265R (100kHz)
3. Pulse by Pulse Over Current Limiting
4. Over Load Protection
5. Over Voltage Protection (Min. 23V)
6. Internal Thermal Shutdown Function
7. Under Voltage Lockout
8. Internal High Voltage Sense FET