1

LTC487

Quad Low Power

RS485 Driver

DESCRIPTIO

2

DRIVER

LTC487 • TA01

RECEIVER

DI

EN 12

4

3

1

1/4 LTC487

120

Ω

120

Ω

RO

3

EN 12

4

2

1

1/4 LTC489

4000 FT BELDEN 9841

s

s

Designed for RS485 or RS422 Applications

s

Single 5V Supply

s

– 7V to 12V Bus Common-Mode Range Permits

±7V GND Difference Between Devices on the Bus

s

Thermal Shutdown Protection

s

Power-Up/Down Glitch-Free Driver Outputs Permit

Live Insertion/Removal of Package

s

Driver Maintains High Impedance in Three-State or

with the Power Off

s

28ns Typical Driver Propagation Delays with

5ns Skew

s

Pin Compatible with the SN75174, DS96174,

µA96174, and DS96F174

S

FEATURE

The LTC487

designed for multipoint data transmission standard RS485

applications with extended common-mode range (– 7V to

12V). It also meets RS422 requirements.

The CMOS design offers significant power savings over its

bipolar counterpart without sacrificing ruggedness against

overload or ESD damage.

The driver features three-state outputs, with the driver

outputs maintaining high impedance over the entire com-

mon-mode range. 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.

Both AC and DC specifications are guaranteed from 0

°C to

70

°C (Commercial), –40°C to 85°C (Industrial) and over

the 4.75V to 5.25V supply voltage range.

s

Low Power RS485/RS422 Drivers

s

Level Translator

S

APPLICATI

APPLICATI

TYPICAL

DATA RATE (bps)

10k

10

100

1k

10k

100k

1M

10M

LTC487 • TA09

2.5M

* APPLIES FOR 24 GAUGE, POLYETHYLENE

DIELECTRIC TWISTED PAIR

and LTC are registered trademarks and LT is a trademark of Linear Technology Corporation.

RS485 Cable Length Specification*