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LTC1481

Ultra-Low Power

RS485 Transceiver

with Shutdown

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FEATURE

DESCRIPTIO

The LTC

ceiver designed for data transmission standard RS485

applications. It will also meet the requirements of RS422.

The CMOS design offers significant power savings over its

bipolar counterparts without sacrificing ruggedness against

overload or ESD damage. Typical quiescent current is only

80

µA while operating and less than 1µA in shutdown.

The driver and receiver feature three-state outputs, with

the driver outputs maintaining high impedance over the

entire common-mode range. Excessive power dissipation

caused by bus contention or faults is prevented by a

thermal shutdown circuit which forces the driver outputs

into a high impedance state. The receiver has a fail-safe

feature which guarantees a high output state when the

inputs are left open.

The LTC1481 is fully specified over the commercial and

extended industrial temperature range and is available in

8-pin DIP and SO packages.

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Drivers/Receivers Have

±10kV ESD Protection

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1

µA Quiescent Current in Shutdown Mode

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High Speed: Up to 2.5Mbits/s Data Rate

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Single 5V Supply

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– 7V to 12V Common-Mode Range Permits

±7V

Ground Difference Between Devices on the Data Line

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Thermal Shutdown Protection

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Power Up/Down Glitch-Free Driver Outputs Permit

Live Insertion or Removal of Transceiver

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Driver Maintains High Impedance in Three-State

or with the Power Off

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Up to 32 Transceivers on the Bus

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30ns Typical Driver Propagation Delays

with 5ns Skew

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Pin Compatible with the LTC485

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Battery-Powered RS485/RS422 Applications

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Low Power RS485/RS422 Transceiver

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Level Translator

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APPLICATI

APPLICATI

TYPICAL

TEMPERATURE (°C)

–50

50

350

300

250

200

150

100

50

0

1481 TA02

0

–25

25

75

125

175

150

100

DRIVER ENABLED

DRIVER DISABLED

THERMAL SHUTDOWN

WITH DRIVER ENABLED

GND1

R

RO1

RE1

DE1

DI1

D

GND2

R

RO2

RE2

DE2

DI2

D

Rt

Rt

LTC1481 • TA01

Supply Current vs Temperature

, LTC and LT are registered trademarks of Linear Technology Corporation.