The MOC8111 is an optocoupler consisting of a Gallium Arsenide infrared emitting diode optically coupled to a silicon planar phototransistor detector in a plastic plug-in DIP 6 pin package. The coupling device is suitable for signal transmission between two electrically separated circuits. The potential difference between the circuits to be coupled is not allowed to exceed the maximum permissible reference voltages. In contrast to the IL1 the base terminal is not connected, resulting in a substantially improved common-mode interference immunity. Maximum Ratings (TA=25C)