max485 pdf datasheet

The MAX481E, MAX483E, MAX485E, MAX487E–MAX491E,
and MAX1487E are low-power transceivers for RS-485 and
RS-422 communications in harsh environments. Each driver
output and receiver input is protected against ±15kV electrostatic
discharge (ESD) shocks, without latchup. These parts
contain one driver and one receiver. The MAX483E,
MAX487E, MAX488E, and MAX489E feature reduced slewrate
drivers that minimize EMI and reduce reflections caused
by improperly terminated cables, thus allowing error-free
data transmission up to 250kbps. The driver slew rates of the
MAX481E, MAX485E, MAX490E, MAX491E, and MAX1487E
are not limited, allowing them to transmit up to 2.5Mbps.
These transceivers draw as little as 120μA supply current
when unloaded or when fully loaded with disabled drivers
(see Selection Table). Additionally, the MAX481E,
MAX483E, and MAX487E have a low-current shutdown
mode in which they consume only 0.5μA. All parts operate
from a single +5V supply.
Drivers are short-circuit current limited, and are protected
against excessive power dissipation by thermal shutdown
circuitry that places their outputs into a high-impedance
state. The receiver input has a fail-safe feature that guarantees
a logic-high output if the input is open circuit.
The MAX487E and MAX1487E feature quarter-unit-load
receiver input impedance, allowing up to 128 transceivers
on the bus. The MAX488E–MAX491E are designed for fullduplex
communications, while the MAX481E, MAX483E,
MAX485E, MAX487E, and MAX1487E are designed for halfduplex
applications. For applications that are not ESD sensitive
see the pin- and function-compatible MAX481,
MAX483, MAX485, MAX487–MAX491, and MAX1487.
________________________Applications
Low-Power RS-485 Transceivers
Low-Power RS-422 Transceivers
Level Translators
Transceivers for EMI-Sensitive Applications
Industrial-Control Local Area Networks