This part is a kind of semiconductor called 357NT.

Function of this product has KPC357NT.

Manufacturers : COSMO Electronics Corporation

Image and pinout :

Some of the text within the PDF file :

Hemar AG, Fendler 50, CH-5524 Nesselnbach, Tel: +41 (0)56 618 31 41, Fax +41 (0)56 618 31 42 http://www.hemar.ch Mini-flat package General purpose Photo Coupler KPC357NT UL 1577 (File No.E169586) Features 1. Opaque type, mini-flat package. 2. Subminiature type (The volume is smaller than that of our conventional DIP type by as far as 30%). 3. Current transfer ratio (CTR:MIN.50% at IF=5mA, Vce=5V) 4. Isolation voltage between input and output (Viso:3750Vrms). Outside Dimension : Unit (mm) Applications 1. Hybrid substrates that reguire high density mounting. 2. Programmable controllers. Classification table of current transfer ratio is shown below. t=0.254+0.05mm TOLERANCE :+ 0.2mm Schematic : Top View 1. Anode 2. Cathode 3. Emitter 4. Collector Absolute Maximum Ratings Input Output [ ... ]

357NT PDF Datasheet Download