Photocoupler. Operating Ambient Temperature 110°C. The PS2561D-1 is an optically coupled isolator containing a GaAs light emitting diode and an NPN silicon phototransistor. The PS2561D-1 is in a plastic DIP (Dual In-line Package) and the PS2561DL-1 is lead bending type (Gull-wing) for surface mount. The PS2561DL-1 is lead bending type for long creepage distance. The PS2561DL2-1 is lead bending type for long creepage distance (Gull-wing) for surface mount.