The ADM3485E is a 3.3 V, low power data transceiver with ±15 kV ESD protection, suitable for half-duplex communication on multipoint bus transmission lines. The ADM3485E is designed for balanced data transmission and complies with TIA/EIA standards RS485 and RS-422. The ADM3485E is a half-duplex transceiver that shares differential lines and has separate enable inputs for the driver and the receiver.
The devices have a 12 kΩ receiver input impedance, which allows up to 32 transceivers on a bus. Because only one driver should be enabled at any time, the output of a disabled or powered-down driver is tristated to avoid overloading the bus.
The receiver has a fail-safe feature that ensures a logic high output when the inputs are floating. Excessive power dissipation caused by bus contention or by output shorting is prevented with a thermal shutdown circuit.
The part is fully specified over the industrial temperature range and is available in an 8-lead narrow SOIC package.
