This part is a kind of semiconductor called GS400SD.

Function of this product has SURFACE MOUNT SCHOTTKY BARRIER DIODE.

Manufacturers : GTM

Image and pinout :

Some of the text within the PDF file :

CORPORATION GS400SD Description Package Dimensions ISSUED DATE :2005/12/20 REVISED DATE : S U R F A C E M O U N T, S C H O T T K Y B A R R I E R D I O D E V O LT A G E 4 0 V, C U R R E N T 0 . 5 A The GS400SD is high frequency rectification for switching power supply. REF. A A1 A2 D E HE Millimeter Min. Max. 0.80 1.10 0 0.10 0.80 1.00 1.80 2.20 1.15 1.35 1.80 2.40 REF. L1 L b c e Q1 Millimeter Min. Max. 0.42 REF. 0.15 0.35 0.25 0.40 0.10 0.25 0.65 REF. 0.15 BSC. Absolute Maximum Ratings at TA = 25 Parameter Junction Temperature Storage Temperature Maximum Recurrent Peak Reverse Voltage Maximum RMS Voltage Maximum DC Blocking Voltage Peak Forward Surge Current at 8.3mSec single half sine-wave Typical Junction Capacitance between Terminal (Note 1) Maximum Average [ ... ]

GS400SD PDF Datasheet Download