This part is a kind of semiconductor called AN606.

Function of this product has Current Sensing Power MOSFETs.

Manufacturers : Vishay

Image and pinout :

Some of the text within the PDF file :

AN606 Vishay Siliconix Current-Sensing Power MOSFETs Kandarp Pandya INTRODUCTION Vishay Siliconix current-sensing power MOSFETs offer a simple means of incorporating a protection feature into an electronic control circuit and avoiding catastrophic failures resulting from overcurrent (overload) and/or short-circuit conditions. The device package is a modified D2PAK with five pins. The MOSFET termination retains the standard D2PAK footprint for a three-pin device. The additional two pins provide termination for a current-sense output and an internal Kelvin connection to the source. For current sensing, the MOSFET design employs a small number of the total number of MOSFET cells in a known ratio. The latter define the current-sense parameters. A typical control interface uses a simple circu [ ... ]

AN606 PDF Datasheet Download