TLP172A(F)

The Toshiba TLP172A consists of a gallium arsenide infrared emitting diode optically coupled to a photo-MOSFET in a 4-pin SOP package. This photorelay has higher output current rating than phototransistor-type photocoupler; hence, it is suitable for use as On/Off control for high current. 

 4-pin SOP (2.54SOP4): Height = 2.1 mm, pitch = 2.54 mm
 Normally open (1-form-A) device
 Peak off-state voltage: 60 V (min)
 Trigger LED current: 3 mA (max)
 On-state current: 400 mA (max)
 On-state resistance: 2 Ω (max)
 Isolation voltage: 1500 Vrms (min)
 UL recognized: UL1557, File No.E67349

(Picture: Pinout)