This part is a kind of semiconductor called 378R12.

Function of this product has KA378R12.

Manufacturers : Fairchild Semiconductor

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Some of the text within the PDF file :

www.fairchildsemi.com KA378R12 Low Dropout Voltage Regulator Features • • • • • 3A/12V Output Low Dropout Voltage Regulator TO-220 Full-Mold Package (4Pin) Overcurrent Protection, Thermal Shutdown Overvoltage Protection, Short Circuit Protection With Output Disable Function Description The KA378R12 is a low-dropout voltage regulator suitable for various electronic equipments. It provide constant voltage power source with TO-220 4 lead full mold package. Dropout voltage of KA378R12 is below 0.5V in full rated current(3A). This regulator has various function such as peak current protection, thermal shut down, overvoltage protection and output disable function. TO-220F-4L 1 1. Vin 2. Vo 3. GND 4. Vdis Internal Block Diagram Q1 Vin 1 2 Vo THERMAL SHUTD [ ... ]

378R12 PDF Datasheet Download