This is one of the semiconductor types. This part name is TNY178PN.
This product has (TNY174 – TNY180) Offline Switcher functions.
Manufacturers of product is Power Integrations.
Image and pinout :
TNY178PN PDF Datasheet
Some of the text files within the PDF file
TNY174-180 ® TinySwitch-LT Family Energy Efﬁcient, Ofﬂine Switcher with Enhanced Flexibility and Extended Power Range Product Highlights Lowest System Cost with Enhanced Flexibility • 650 V rating optimized for non-active PFC applications • Simple ON/OFF control, no loop compensation needed • Selectable current limit through BP/M capacitor value – Higher current limit extends peak power or, in open frame applications, maximum continuous power – Lower current limit improves efﬁciency in enclosed adapters/chargers – Allows optimum TinySwitch-LT choice by swapping devices with no other circuit redesign • Tight I2f parameter tolerance reduces system cost – Maximizes MOSFET and magnetics power delivery – Minimizes max overload power, reducing cost of transformer, primary clamp & secondary components • ON-time extension – extends low line regulation range/ hold-up time to reduce input bulk capacitance • Self-biased: no bias winding or bias components [ … ]
Please refer to the file for details.