This part is a kind of semiconductor called BAT54.

Function of this product has Schottky barrier double diodes.

Manufacturers : NXP

Image and pinout :

Some of the text within the PDF file :

SOT23 BAT54 series Schottky barrier diodes Rev. 5 5 October 2012 Product data sheet 1. Product profile 1.1 General description Planar Schottky barrier diodes with an integrated guard ring for stress protection, encapsulated in a small SOT23 (TO-236AB) Surface-Mounted Device (SMD) plastic package. 1.2 Features and benefits  Low forward voltage  Low capacitance  AEC-Q101 qualified 1.3 Applications  Ultra high-speed switching  Line termination  Voltage clamping  Reverse polarity protection 1.4 Quick reference data Table 1. Quick reference data Tamb = 25 C unless otherwise specified. Symbol Parameter Conditions Per diode VR reverse voltage VF forward voltage IF = 100 mA IR reverse current VR = 25 V [1] Pulse test: tp  300 s;   0.02. 2. [ ... ]

BAT54 PDF Datasheet Download