This part is a kind of semiconductor called DTC124ES3.

Function of this product has PNP Digital Transistors.

Manufacturers : Cystech

Image and pinout :

Some of the text within the PDF file :

CYStech Electronics Corp. PNP Digital Transistors (Built-in Resistors) Spec. No. : C263S3 Issued Date : 2003.07.29 Revised Date : 2004.03.03 Page No. : 1/4 DTA124ES3 • Built-in bias resistors enable the configuration of an inverter circuit without connecting external input resistors (see equivalent circuit). • The bias resistors consist of thin-film resistors with complete isolation to allow positive biasing of the input. They also have the advantage of almost completely eliminating parasitic effects. • Only the on/off conditions need to be set for operation, making device design easy. • Complements the DTC124ES3 Features Equivalent Circuit DTA124ES3 Outline SOT-323 R1=22kΩ , R2=22 kΩ IN(B) : Base OUT(C) : Collector GND(E) : Emitter Absolute Maximum R [ ... ]

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