ADM3072E: 3.3V ±15kV ESD Protected Half Duplex Driver/Receiver Enable Transceiver w/250kbps

The ADM3070E–ADM3076E are 3.3V, low power data transceivers with ±15kV ESD protection suitable for full and half duplex communication on multipoint bus transmission lines. They are designed for balanced data transmission and comply with TIA/EIA standards RS-485 and RS-422. The devices have a 1/8 unit load receiver input impedance which allows up to 256 transceivers on a bus. Since only one driver should be enabled at any time, the output of a disabled or powered down driver is three-stated to avoid overloading the bus.

The receiver inputs have a true failsafe feature which eliminates the need for external bias resistors and ensures a logic high output level when the inputs are open or shorted. This guarantees that the receiver outputs are in a known state before communication begins and when communication ceases.

The driver outputs are slew rate limited in order to reduce EMI and data errors caused by reflections from improperly terminated buses. Excessive power dissipation caused by bus contention or by output shorting is prevented with a thermal shutdown circuit.

The parts are fully specified over the industrial and automotive temperature ranges and are available in 8-lead and 14-lead SOIC packages.

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