1
LTC487
Quad Low Power
RS485 Driver
D
U
ESCRIPTIO
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
■
Very Low Power: I
CC
= 110
µ
A 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,
µ
A96174, and DS96F174
S
FEATURE
The LTC487
®
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.
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.
■
Low Power RS485/RS422 Drivers
■
Level Translator
U
S
A
O
PPLICATI
U
A
O
PPLICATI
TYPICAL
DATA RATE (bps)
10k
10
CABLE LENGTH (FT)
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*