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LTC1485

Differential Bus Transceiver

DESCRIPTIO

S

FEATURE

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

APPLICATI

TYPICAL

DI

RO

4

3

6

7

2

DE

120

Ω

120

Ω

DRIVER

RECEIVER

DE

3

4

RO

DI

2

1

6

7

4000 FT 24 GAUGE TWISTED PAIR

1485 TA01

LTC1485

LTC1485

RECEIVER

DRIVER

RE

RE

8

5V

8

5V

5

5

1

The LTC

ceiver 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 with Schottky design offers significant power

savings over its bipolar counterpart without sacrificing

ruggedness against overload or ESD damage.

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. I/O pins are protected against

multiple ESD strikes of over

±10kV.

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 – 40

°C

to 85

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

s

Low Power RS485/RS422 Transceiver

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Level Translator

S

APPLICATI

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ESD Protection over

s

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28ns Typical Driver Propagation Delays with

4ns Skew

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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

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Driver Maintains High Impedance in Three-State or

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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60mV Typical Input Hysteresis

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Pin Compatible with the SN75176A, DS75176A, and

SN75LBC176