LTC487
Quad Low Power
RS485 Driver
FEATURES
DESCRIPTION
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The LTC®487 is a low power differential bus/line driver
designed for multipoint data transmission standard RS485
applications with extended common-mode range (– 7V to
12V). It also meets RS422 requirements.
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Very Low Power: ICC = 110μA Typ
Designed for RS485 or RS422 Applications
Single 5V Supply
– 7V to 12V Bus Common-Mode Range Permits ±7V
GND Difference Between Devices on the Bus
Thermal Shutdown Protection
Power-Up/Down Glitch-Free Driver Outputs Permit
Live Insertion/Removal of Package
Driver Maintains High Impedance in Three-State or
with the Power Off
28ns Typical Driver Propagation Delays with
5ns Skew
Pin Compatible with the SN75174, DS96174,
μA96174, and DS96F174
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
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.
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.
APPLICATIONS
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Low Power RS485/RS422 Drivers
Level Translator
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
TYPICAL APPLICATION
RS485 Cable Length Specification*
10k
EN 12
4
4
2
DI
1
2
120Ω
DRIVER
3
120Ω
4000 FT BELDEN 9841
RECEIVER
1
3
RO
1/4 LTC489
CABLE LENGTH (FT)
EN 12
1k
100
1/4 LTC487
LTC487 TA01
10
10k
100k
1M
2.5M
10M
DATA RATE (bps)
LTC487 TA09
* APPLIES FOR 24 GAUGE, POLYETHYLENE
DIELECTRIC TWISTED PAIR
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