High Speed, ESD-Protected, Full-Duplex,
iCoupler Isolated RS-485 Transceiver
ADM2490E
Rev. A
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FEATURES
Isolated, full-duplex RS-485/RS-422 transceiver
±8 kV ESD protection on RS-485 input/output pins
16 Mbps data rate
Complies with ANSI TIA/EIA-485-A-1998 and
ISO 8482: 1987(E)
Suitable for 5 V or 3 V operation (V
DD1
)
High common-mode transient immunity: >25 kV/μs
Receiver has open-circuit, fail-safe design
32 nodes on the bus
Thermal shutdown protection
Safety and regulatory approvals
UL recognition: 5000 V rms isolation voltage
for 1 minute per UL 1577
VDE certificate of conformity
DIN EN 60747-5-2 (VDE 0884-10 Part 2): 2003-01
DIN EN 60950 (VDE 0805): 2001-12; EN 60950: 2000
V
IORM
= 848 V peak
Operating temperature range: −40°C to +105°C
Wide body, 16-lead SOIC package
APPLICATIONS
Isolated RS-485/RS-422 interfaces
Industrial field networks
INTERBUS
Multipoint data transmission systems
FUNCTIONAL BLOCK DIAGRAM
DD1
GND
1
A
B
DD2
GND
2
GALVANIC ISOLATION
Y
Z
TxD
RxD
ADM2490E
05889-001
Figure 1.
GENERAL DESCRIPTION
The ADM2490E is an isolated data transceiver with ±8 kV ESD
protection that is suitable for high speed, full-duplex communi-
cation on multipoint transmission lines. It is designed for balanced
transmission lines and complies with ANSI TIA/EIA-485-A-1998
and ISO 8482: 1987(E). The device employs Analog Devices, Inc.,
iCoupler® technology to combine a 2-channel isolator, a three-
state differential line driver, and a differential input receiver into
a single package.
The differential transmitter outputs and receiver inputs feature
electrostatic discharge circuitry that provides protection to ±8 kV
using the human body model (HBM). The logic side of the device
can be powered with either a 5 V or a 3 V supply, whereas the
bus side requires an isolated 5 V supply.
The device has current-limiting and thermal shutdown features
to protect against output short circuits and situations where bus
contention could cause excessive power dissipation.
The ADM2490E is available in a wide body, 16-lead SOIC package
and operates over the −40°C to +105°C temperature range.
