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LTC1690

Differential Driver and

Receiver Pair with Fail-Safe

Receiver Output

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

The LTC

compatible with the requirements of RS485 and RS422.

The receiver offers a fail-safe feature that guarantees a

high receiver output state when the inputs are left open,

shorted together or terminated with no signal present. No

external components are required to ensure the high

receiver output state.

Separate driver output and receiver input pins allow full

duplex operation. Excessive power dissipation caused by

bus contention or faults is prevented by a thermal shut-

down circuit which forces the driver outputs into a high

impedance state.

The LTC1690 is fully specified over the commercial and

industrial temperature ranges. The LTC1690 is available in

8-Pin SO, MSOP and PDIP packages.

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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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Line Repeater

120

Ω

3

5

6

D1

120

Ω

2

8

7

R2

DRIVER

LTC1690

LTC1690

RECEIVER

120

Ω

2

7

8

Y1

Z1

B1

A1

A2

B2

Z2

Y2

R1

120

Ω

3

6

5

D2

RECEIVER

DRIVER

1690 TA01

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No Damage or Latchup to

Model), IEC1000-4-2 Level 4 (

Level 3 (

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Guaranteed High Receiver Output State for

Floating, Shorted or Terminated Inputs with No

Signal Present

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Drives Low Cost Residential Telephone Wires

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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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Power-Up/Down Glitch-Free Driver Outputs Permit

Live Insertion or Removal of Transceiver

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Driver Maintains High Impedance with the Power Off

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Up to 32 Transceivers on the Bus

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Pin Compatible with the SN75179 and LTC490

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Available in SO, MSOP and PDIP Packages

D1

B2

A2

R2

1690 TA01a

APPLICATIO S

FEATURES

TYPICAL APPLICATIO

DESCRIPTIO

Driving a 1000 Foot STP Cable