The KIR5105J-D with Optical Sensors SMD RoHS is a standard four-pin opto-coupler manufactured by Kodenshi. This device is surface-mountable and features a phototransistor and an infrared LED in a small, compact SMD package. It is RoHS compliant and offers a wide current transfer ratio and minimum leakage current for reliable performance in all types of applications. The KIR5105J-D is suitable for use in digital output switching, protection circuits, and signal transmission and isolation circuits. It can be used to provide isolation of logic signal lines in both AC and DC systems.