Analog Devices LTC1535

Description

The LTC®1535 is an isolated RS485 full-duplex differentialline transceiver. Isolated RS485 is ideal for systems wherethe ground loop is broken to allow for much larger commonmode voltage ranges. An internal capacitive isolationbarrier provides 2500VRMS of isolation between theline transceiver and the logic level interface. The poweredside contains a 420kHz push-pull converter to power theisolated RS485 transceiver. Internal full-duplex communicationoccurs through the capacitive isolation barrier.The transceiver meets RS485 and RS422 requirements.The driver and receiver feature three-state outputs, withthe driver maintaining high impedance over the entirecommon mode range. The drivers have short-circuit currentlimits in both directions and a slow slew rate selectto minimize EMI or reflections. The 68kΩ receiver inputallows up to 128 node connections. A fail-safe featuredefaults to a high output state when the receiver inputsare open or shorted.

Features

UL Rated Isolated RS485: 2500VRMSUL Recognized ® File #E151738n Eliminates Ground Loopsn 250kBd Maximum Data Raten Self-Powered with 420kHz Convertern Half- or Full-Duplexn Fail-Safe Output High for Open orShorted Receiver Inputsn Short-Circuit Current Limitn Slow Slew Rate Controln 68kΩ Input Impedance Allows Up to 128 Nodesn Thermal Shutdownn 8kV ESD Protection On Driver Outputs andReceiver Inputsn Available in 28-Lead SW Package

Typical applications

• Isolated RS485 Receiver/Driver,RS485 with Large Common Mode Voltage,Breaking RS485 Ground Loops,Multiple Unterminated Line Taps

More information

• Datasheet
• IC product information