This part is a kind of semiconductor called 47CTQ020.

Function of this product has SCHOTTKY RECTIFIER.

Manufacturers : International Rectifier

Image and pinout :

Some of the text within the PDF file :

PD-20540 rev. E 10/99 47CTQ020 47CTQ020S 47CTQ020-1 SCHOTTKY RECTIFIER 40 Amp Major Ratings and Characteristics Characteristics IF(AV) Rectangular waveform VRRM IFSM @ tp = 5 µs sine VF TJ @ 20 Apk, TJ = 125 °C Description/Features Units A V A V °C This center tap Schottky rectifier has been optimized for ultra low forward voltage drop specifically for 3.3V output power supplies. The proprietary barrier technology allows for reliable operation up to 150 °C junction temperature. Typical applications are in parallel switching power supplies, converters, reverse battery protection, and redundant power subsystems. Center tap configuration Optimized for 3.3V application Ultra low forward voltage drop High frequency operation Guard ring for enhanced ruggedness and long term reliability Hi [ ... ]

47CTQ020 PDF Datasheet Download