This part is a kind of semiconductor called TOP250.

Function of this product has (TOP242 - TOP250) up to 290 W Extended Power / Integrated Off-line Switcher Family.

Manufacturers : Power Integrations

Image and pinout :

Some of the text within the PDF file :

TOP242-250 TOPSwitch -GX Family Extended Power, Design Flexible, ® EcoSmart, Integrated Off-line Switcher Product Highlights Lower System Cost, High Design Flexibility • Extended power range for higher power applications • No heatsink required up to 30 W using P package • Features eliminate or reduce cost of external components • Fully integrated soft-start for minimum stress/overshoot • Externally programmable accurate current limit • Wider duty cycle for more power, smaller input capacitor • Separate line sense and current limit pins on Y/R/F packages • Line under-voltage (UV) detection: no turn off glitches • Line overvoltage (OV) shutdown extends line surge limit • Line feed forward with maximum duty cycle (DCMAX) reduction rejects line ripple [ ... ]

TOP250 PDF Datasheet Download