The NM232DDC is an electrically isolated Dual Transmitter and Receiver designed to interface data terminal equipment (DTE) with data communications equipment (DCE). The device provides two data receive channels and two data transmit channels. Each channel is EIA-232-D, EIA-232-E and CCITT V.28 compatible at the interface boundary and TTL/CMOS compatible at the logic connections. No external components are needed and a single 5V input supply powers all functions either side of the isolation boundary. A low-power shutdown mode and high impedance state for receiver outputs is effected via two pins, SHUTDOWN and ENABLE.