LTC1485
Differential Bus Transceiver
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DESCRIPTIO
FEATURES
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ESD Protection over ±10kV
Low Power: ICC = 1.8mA Typ
28ns Typical Driver Propagation Delays with
4ns Skew
Designed for RS485 or RS422 Applications
Single 5V Supply
– 7V to 12V Bus Common-Mode Range Permits ±7V
Ground Difference Between Devices on the Bus
Thermal Shutdown Protection
Power-Up/Down Glitch-Free Driver Outputs
Driver Maintains High Impedance in Three-State or
with the Power Off
Combined Impedance of a Driver Output and
Receiver Allows up to 32 Transceivers on the Bus
60mV Typical Input Hysteresis
Pin Compatible with the SN75176A, DS75176A, and
SN75LBC176
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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.
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Low Power RS485/RS422 Transceiver
Level Translator
, LTC and LT are registered trademarks of Linear Technology Corporation.
UO
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The CMOS with Schottky design offers significant power
savings over its bipolar counterpart without sacrificing
ruggedness against overload or ESD damage.
Both AC and DC specifications are guaranteed from – 40°C
to 85°C and 4.75V to 5.25V supply voltage range.
UO
APPLICATI
The LTC ®1485 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.
TYPICAL APPLICATI
DE
5V
5V
3
8
8
LTC1485
LTC1485
6
6
DI
4
120Ω
DRIVER
7
RO
1
120Ω
4000 FT 24 GAUGE TWISTED PAIR
DRIVER
RE
RECEIVER
5
4
DI
7
RECEIVER
2
DE
3
5
1
RO
2
RE
1485 TA01
1
