This part is a kind of semiconductor called BA1.5WK.

Function of this product has MINIATURE RELAY.

Manufacturers : Fujitsu

Image and pinout :

Some of the text within the PDF file :

MINIATURE RELAY 2 POLES1 to 2 A (FOR SIGNAL SWITCHING) BA SERIES s FEATURES q q q q q q q q q Slim type relay for high density mounting CSA recognized Conforms to IEC60950, Bellcore specification and FCC Part 68 Clearance more than 2.0 mm between coil and contacts Creepage more than 2.5 mm between coil and contacts Dielectric strength 2,000 VAC between coil and contacts Surge strength 3,000 V between coil and contacts (at 2 × 10 µs surge wave) High sensitivity and low consumption power Latching type available High reliabilitybifurcated contacts Plastic sealed type Conforms to UL (under approval) SMT is available: BAS s ORDERING INFORMATION [Example] (a) (b) (c) (d) (e) (g) BA L – D (a) (b) (*) (c) 12 (d) W K (e) (g) BA : BA Series Nil : Standard type L : Latch [ ... ]

BA1.5WK PDF Datasheet Download