This part is a kind of semiconductor called ADP-G2.

Function of this product has 5W Small AC Adaptors.

Manufacturers : Mitsumi Electronics

Image and pinout :

Some of the text within the PDF file :

MITSUMI 5W Small AC Adaptors with Worldwide Input ADP-G2 Series Adaptors, Chargers OUTLINE Ultra-small inlet type AC adaptor with 5W output capacity. Can meet safety standards for all destinations. FEATURES 1. Standard Mitsumi case. 2. Input voltage supports worldwide input. 3. Output specifications can be customized. USES 1. Small electronic equipment. 2. Mobile telephones. SPECIFICATIONS Item Input voltage Output capacity Destinations Safety standards External dimensions Specifications AC 100~240V 5W Whole-world correspondence Conforms to IEC60950 38 (W) 63 (L) 20 (H) mm MITSUMI 5W Small AC Adaptors with Worldwide Input DIMENSIONS 20 38 63 Unit: mm [ ... ]

ADP-G2 PDF Datasheet Download