ADM1491EBRMZ IC ADI

The ADM1490E/ADM1491E are RS-485/RS-422 transceiverswith ±8 kV ESD protection and are suitable for high speed, fullduplex communication on multipoint transmission lines.

Inparticular, the ADM1490E/ADM1491E are designed for use inmotor control applications requiring communications at datarates up to 16 Mbps.

The ADM1490E/ADM1491E are designed for balanced transmission lines and comply with TIA/EIA-485-A-98. The deviceseach have a 12 kΩ receiver input impedance for unit load RS-485operation, allowing up to 32 nodes on the bus.The differential transmitter outputs and receiver inputs featureelectrostatic discharge circuitry that provides protection to ±8 kVusing the human body model (HBM).

The ADM1490E/ADM1491E operate from a single 5 V powersupply. Excessive power dissipation caused by bus contentionor output shorting is prevented by short-circuit protection andthermal circuitry.

Short-circuit protection circuits limit themaximum output current to ±250 mA during fault conditions.A thermal shutdown circuit senses if the die temperature risesabove 150°C and forces the driver outputs into a high impedancestate under this condition.

The receiver of the ADM1490E/ADM1491E contains a fail-safefeature that results in a logic high output state if the inputs areunconnected (floating).The ADM1490E/ADM1491E feature extremely fast and closelymatched switching times.

Minimal driver propagation delayspermit transmission at data rates up to 16 Mbps, and low skewminimizes EMI interference.The ADM1490E/ADM1491E are fully specified over thecommercial and industrial temperature ranges. The ADM1490Eis available in two packages: a narrow body, 8-lead SOIC and an8-lead MSOP. The ADM1491E is also available in two packages:a narrow body, 14-lead SOIC and a 10-lead MSOP.