Integrated Semiconductor Electronic Chip Board MAX485CSA Slew Rate
Limited
MAX485CSA Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers
General Description
The MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 are
low-power transceivers for RS-485 and RS- 422 communication. Each
part contains one driver and one receiver. The MAX483, MAX487,
MAX488, and MAX489 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 MAX481, MAX485, MAX490, MAX491, and
MAX1487 are not limited, allowing them to transmit up to 2.5Mbps.
These transceivers draw between 120µA and 500µA of supply current
when unloaded or fully loaded with disabled drivers. Additionally,
the MAX481, MAX483, and MAX487 have a low-current shutdown mode in
which they consume only 0.1µA. 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 the driver 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 MAX487 and MAX1487 feature
quarter-unit-load receiver input impedance, allowing up to 128
MAX487/ MAX1487 transceivers on the bus. Full-duplex communications
are obtained using the MAX488–MAX491, while the MAX481, MAX483,
MAX485, MAX487, and MAX1487 are designed for half-duplex
applications.
_Next Generation Device Features
♦ For Fault-Tolerant Applications
MAX3430: ±80V Fault-Protected, Fail-Safe, 1/4 Unit Load, +3.3V,
RS-485 Transceiver
MAX3440E–MAX3444E: ±15kV ESD-Protected, ±60V Fault-Protected,
10Mbps, Fail-Safe, RS-485/J1708 Transceivers
♦ For Space-Constrained Applications
MAX3460–MAX3464: +5V, Fail-Safe, 20Mbps, Profibus RS-485/RS-422
Transceivers
MAX3362: +3.3V, High-Speed, RS-485/RS-422 Transceiver in a SOT23
Package
MAX3280E–MAX3284E: ±15kV ESD-Protected, 52Mbps, +3V to +5.5V,
SOT23, RS-485/RS-422,
True Fail-Safe Receivers
MAX3293/MAX3294/MAX3295: 20Mbps, +3.3V, SOT23, RS-855/RS-422
Transmitters
♦ For Multiple Transceiver Applications
MAX3030E–MAX3033E: ±15kV ESD-Protected, +3.3V, Quad RS-422
Transmitters
♦ For Fail-Safe Applications MAX3080–MAX3089: Fail-Safe, High-Speed
(10Mbps),
Slew-Rate-Limited RS-485/RS-422 Transceivers
♦ For Low-Voltage Applications
MAX3483E/MAX3485E/MAX3486E/MAX3488E/ MAX3490E/MAX3491E: +3.3V
Powered, ±15kV ESD-Protected, 12Mbps, Slew-Rate-Limited, True
RS-485/RS-422 Transceivers
___Applications
Low-Power RS-485 Transceivers
Low-Power RS-422 Transceivers
Level Translators Transceivers for EMI-Sensitive
Applications Industrial-Control Local Area Networks
NOTES FOR ELECTRICAL/SWITCHING CHARACTERISTICS
Note 1: All currents into device pins are positive; all currents
out of device pins are negative. All voltages are referenced to
device ground unless otherwise specified.
Note 2: All typical specifications are given for VCC = 5V and TA =
+25°C.
Note 3: Supply current specification is valid for loaded
transmitters when DE = 0V.
Note 4: Applies to peak current. See Typical Operating
Characteristics.
Note 5: The MAX481/MAX483/MAX487 are put into shutdown by bringing
RE high and DE low. If the inputs are in this state for less than
50ns, the parts are guaranteed not to enter shutdown. If the inputs
are in this state for at least 600ns, the parts are guaranteed to
have entered shutdown. See Low-Power Shutdown Mode section.
Typical Operating Characteristics
