Support is limited to customers who have already adopted these products. The PS2561B-1 is an optically coupled isolator containing a GaAs light emitting diode and an NPN silicon phototransistor. The PS2561B-1 is in a plastic DIP (Dual In-line Package) and the PS2561BL-1 is lead bending type (Gull-wing) for surface mount. The PS2561BL1-1 is lead bending type for long creepage distance. The PS2561BL2-1 is lead bending type for long creepage distance (Gull-wing) for surface mount.