ADM3485EARZ-REEL7

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.

Applications

• Power/energy metering
• Telecommunications
• EMI-sensitive systems
• Industrial control
• Local area networks

Key features

• TIA/EIA RS-485/RS-422 compliant
• ±15 kV ESD protection on RS-485 input/output pins
• 12 Mbps data rate
• Half-duplex transceiver
• Up to 32 nodes on the bus
• Receiver open-circuit, fail-safe design
• Low power shutdown current
• Outputs high-Z when disabled or powered off
• Common-mode input range: −7 V to +12 V
• Thermal shutdown and short-circuit protection
• Industry-standard 75176 pinout
• 8-lead narrow SOIC package