The Vishay optocoupler have a GaAs infrared emitting diode emitter, which is optically coupled to a silicon planar phototransistor detector, and is incorporated in a plastic DIP-4 package. The coupling devices are designed for signal transmission between two electrically separated circuits.Low CTR degradationGood CTR linearity depending on forward currentFast switching timesTemperature stableLow coupling capacitanceHigh common mode interference immunity