This part is a kind of semiconductor called A1757.

Function of this product has UPA1757.

Manufacturers : NEC

Image and pinout :

Some of the text within the PDF file :

DATA SHEET MOS FIELD EFFECT TRANSISTOR µ PA1757 SWITCHING N-CHANNEL POWER MOS FET INDUSTRIAL USE Description This product is Dual N-Channel MOS Field Effect Transistor Package Drawing (Unit : mm) designed for power management application of notebook computers, and Li-ion battery application. 8 5 1 ; Source 1 2 ; Gate 1 7, 8 ; Drain 1 3 ; Source 2 4 ; Gate 2 5, 6 ; Drain 2 1 4 5.37 Max. +0.10 –0.05 Features • Dual MOS FET chips in small package • 2.5 V gate drive type and low on-resistance RDS(on)1 = 23 mΩ (MAX.) (VGS = 4.5 V, ID = 3.5 A) 1.44 6.0 ±0.3 4.4 0.8 RDS(on)2 = 32 mΩ (MAX.) (VGS = 2.5 V, ID = 3.5 A) • Built-in G-S protection diode • Small and surface mount package (Power SOP8) 1.8 Max. • Low Ciss Ciss = 750 pF Typ. 0.15 0.05 Min. [ ... ]

A1757 PDF Datasheet Download