Support is limited to customers who have already adopted these products. The PS2503-1 and PS2503L-1 are optically coupled isolators containing a GaAs light emitting diode and an NPN silicon phototransistor. The PS2503-1 is in a plastic DIP (Dual In-line Package) and the PS2503L-1 is lead bending type (Gull-wing) for surface mount.