1

LTC490

Differential Driver and

Receiver Pair

DESCRIPTIO

S

FEATURE

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s

Designed for RS485 or RS422 Applications

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Single 5V Supply

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– 7V to 12V Bus Common-Mode Range

Permits

±7V Ground Difference Between Devices

on the Bus

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Thermal Shutdown Protection

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Power-Up/Down Glitch-Free Driver Outputs Permit

Live Insertion or Removal of Package

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Driver Maintains High Impedance with the

Power Off

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Combined Impedance of a Driver Output and

Receiver Allows up to 32 Transceivers on the Bus

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70mV Typical Input Hysteresis

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28ns Typical Driver Propagation Delays with

5ns Skew

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Pin Compatible with the SN75179

The LTC490 is a low power differential bus/line transceiver

designed for multipoint data transmission standard RS485

applications with extended common-mode range (12V to

–7V). It also meets the requirements of RS422.

The CMOS design offers significant power savings over its

bipolar counterpart without sacrificing ruggedness against

overload or ESD damage.

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.

Both AC and DC specifications are guaranteed from 0

°C to

70

°C and 4.75V to 5.25V supply voltage range.

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APPLICATI

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Low Power RS485/RS422 Transceiver

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Level Translator

APPLICATI

TYPICAL

LTC490 • TA01

120

Ω

120

Ω

120

Ω

120

Ω

4000 FT BELDEN 9841

4000 FT BELDEN 9841

RECEIVER

LTC490

DRIVER

RECEIVER

LTC490

DRIVER

R

D

R

D

3

2

7

8

6

5