PRELIMINARY TECHNICAL DATA
High-Speed(10Mbps),Fail-Safe,RS-485/RS-422
TransceiverswithSlew-Rate-Limiting
a
and 15ꢀkꢁSꢂ ꢃrꢄtectiꢄn
AꢂM3082/AꢂM3085/AꢂM3088
FEATURES
GENERAL DESCRIPTION
Enhanced Slew Rate Limiting for Error-Free Data
Transmission
The ADM3082/ADM3085/ADM3088 are high-speed
RS-485/RS-422 transceivers consisting of one driver and one
receiver per package. The devices feature fail-safe operation,
ensuring a logic-high receiver output when the receiver in-
puts are open-circuit or short-circuit. This guarantees that
the receiver output will be high if all the transmitters on a
terminated bus are disabled (high-impedance).
Fail-Safe Receiver Operation while Maintaining
EIA/TIA-485 compatibility
Low-Current (1nA) Shutdown Mode
High Input Impedance — Up to 256 Transceivers on Bus
15ꢀk ESD ꢁrotection (Human Body Model) on
RS-485 I/O pins
The ADM3082 has a slew-rate limited driver to minimize
electromagnetic interference (EMI) and reduce reflections
caused by incorrectly terminated cables. This allows error-
free transmission at data rates up to 115kbps.
ꢁin-Compatible with Industry Standard 75176
AꢁꢁLICATIONS
Enhanced Replacement for Industry-Standard ꢁarts
EMI-SensitiveSystems
Level Translation
The ADM3085 offers a higher slew rate allowing data rates
up to 500kbps, while the ADM3088 has a driver whose slew
rate is not limited, allowing data rates up to 10Mbps.
All devices in the family feature 15kꢀ electrostatic dis-
charge (ESD) protection and high receiver input imped-
ance (1/8 unit load), allowing up to 256 transceivers on
the bus. The devices have low current drain of 375µA un-
loaded, or fully loaded with the drivers disabled, and fea-
ture an ultra-low power (1nA) shutdown mode.
LANs for Industrial Control Applications
FUNCTIONAL BLOCK DIAGRAM
RO
RE
DE
DI
V
B
A
1
2
3
4
8
7
6
5
CC
R
GND
D
ADM3082/ADM3085/ADM 3088
REV. PrA 02/02
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