MAX485E, MAX487E General Description

[lucyhua]

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 electro-static discharge (ESD) shocks,
without latchup. These parts contain one driver and one
receiver. The MAX483E, MAX487E, MAX488E, and
MAX489E feature reduced slew-rate 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 Selector Guide). 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 full-duplex communications, while the
MAX481E, MAX483E, MAX485E, MAX487E, and
MAX1487E are designed for half-duplex applications.
For applications that are not ESD sensitive see the pinand
function-compatible MAX481, MAX483, MAX485,
MAX487–MAX491, and MAX1487
Details see http://www.html.tai-yan.com
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