16 Mbps, ESD Protected,
Full-Duplex RS-485 Transceivers
RS-485/RS-422 full-duplex transceiver for high speed
motor control applications
16 Mbps data rate
±8 kV ESD protection on RS-485 input/output pins
Complies with ANSI/TIA/EIA-485-A-1998
Open circuit fail-safe
Suitable for 5 V power supply applications
32 nodes on the bus (1 unit load)
Thermal shutdown protection
Operating temperature range: −40°C to +85°C
Narrow body, 8-lead SOIC
Narrow-body, 14-lead SOIC
Industrial field networks
High data rate motor control
Multipoint data transmission systems
Single-ended-to-differential signal conversion
The ADM1490E/ADM1491E are RS-485/RS-422 transceivers
with ±8 kV ESD protection and are suitable for high speed, full-
duplex communication on multipoint transmission lines. In
particular, the ADM1490E/ADM1491E are designed for use in
motor control applications requiring communications at data
rates up to 16 Mbps.
The ADM1490E/ADM1491E are designed for balanced trans-
mission lines and comply with TIA/EIA-485-A-98. The devices
each have a 12 kΩ receiver input impedance for unit load RS-485
operation, allowing up to 32 nodes on the bus.
The differential transmitter outputs and receiver inputs feature
electrostatic discharge circuitry that provides protection to ±8 kV
using the human body model (HBM).
The ADM1490E/ADM1491E operate from a single 5 V power
supply. Excessive power dissipation caused by bus contention
or output shorting is prevented by short-circuit protection and
thermal circuitry. Short-circuit protection circuits limit the
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibilityisassumedbyAnalogDevices for itsuse,nor foranyinfringementsofpatentsor other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
FUNCTIONAL BLOCK DIAGRAMS
maximum output current to ±250 mA during fault conditions.
A thermal shutdown circuit senses if the die temperature rises
above 150°C and forces the driver outputs into a high impedance
state under this condition.
The receiver of the ADM1490E/ADM1491E contains a fail-safe
feature that results in a logic high output state if the inputs are
The ADM1490E/ADM1491E feature extremely fast and closely
matched switching times. Minimal driver propagation delays
permit transmission at data rates up to 16 Mbps, and low skew
minimizes EMI interference.
The ADM1490E/ADM1491E are fully specified over the
commercial and industrial temperature ranges. The ADM1490E
is available in two packages: a narrow body, 8-lead SOIC and an
8-lead MSOP. The ADM1491E is also available in two packages:
a narrow body, 14-lead SOIC and a 10-lead MSOP.
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