Preliminary Technical Data
FEATURES
5 kV rms Signal & Power Isolated RS-485
Transceiver with ±15 kV ESD Protection
ADM2682E/ADM2687E
FUNCTIONAL BLOCK DIAGRAM
V
CC
isoPower
DC-TO-DC CONVERTER
V
ISOOUT
5 kV rms isolated RS-485/RS-422 transceiver, configurable as
half or full duplex
isoPower®
integrated isolated dc-to-dc converter
±15 kV ESD protection on RS-485 input/output pins
Complies with ANSI/TIA/EIA-485-A-98 and ISO 8482:1987(E)
Data rate: 16 Mbps (ADM2682E), 500 kbps (ADM2687E)
5 V or 3.3 V operation
Connect up to 256 nodes on one bus
Open- and short-circuit, fail-safe receiver inputs
High common-mode transient immunity: >25 kV/µs
Thermal shutdown protection
Safety and regulatory approvals
UL recognition (pending)
5000 V rms for 1 minute per UL 1577
CSA Component Acceptance Notice #5A (pending)
IEC 60601-1: 400 V rms (basic), 250 V rms (reinforced)
IEC 60950-1: 600 V rms (basic), 380 V rms (reinforced)
VDE Certificates of Conformity (pending)
DIN EN 60747-5-2 (VDE 0884 Part 2): 2003-01
V
IORM
= 846 V peak
Operating temperature range: −40°C to +85°C
16-lead wide-body SOIC with >8 mm creepage and clearance
OSCILLATOR
RECTIFIER
REGULATOR
V
ISOIN
DIGITAL ISOLATION
iCoupler
ENCODE
DECODE
TRANSCEIVER
Y
TxD
D
Z
DE
ENCODE
DECODE
A
RxD
DECODE
ENCODE
R
B
RE
GND
1
ADM2682E/ADM2687E
ISOLATION
BARRIER
GND
2
Figure 1.
APPLICATIONS
Isolated RS-485/RS-422 interfaces
Industrial field networks
Multipoint data transmission systems
GENERAL DESCRIPTION
The ADM2682E/ADM2687E are fully integrated 5 kV rms
signal and power isolated data transceivers with ±15 kV ESD
protection and are suitable for high speed communication on
multipoint transmission lines. The ADM2682E/ADM2687E
include an integrated 5 kV rms isolated dc-to-dc power supply,
which eliminates the need for an external dc-to-dc isolation
block.
They are designed for balanced transmission lines and comply
with ANSI/TIA/EIA-485-A-98 and ISO 8482:1987(E).
The devices integrate Analog Devices, Inc.,
iCoupler®
technology to
combine a 3-channel isolator, a three-state differential line driver, a
differential input receiver, and Analog Devices
isoPower
dc-to-
dc converter into a single package. The devices are powered by a
single 5 V or 3.3 V supply, realizing a fully integrated signal and
power isolated RS-485 solution.
Rev. PrE
The ADM2682E/ADM2687E driver has an active high enable.
An active low receiver enable is also provided, which causes the
receiver output to enter a high impedance state when disabled.
The devices have current limiting and thermal shutdown
features to protect against output short circuits and situations
where bus contention may cause excessive power dissipation.
The parts are fully specified over the industrial temperature
range and are available in a highly integrated, 16-lead, wide-
body SOIC package with >8 mm creepage and clearance.
The ADM2682E/ADM2687E contain
isoPower
technology that
uses high frequency switching elements to transfer power through
the transformer. Special care must be taken during printed circuit
board (PCB) layout to meet emissions standards. Refer to
Application Note AN-0971,
Control of Radiated Emissions with
isoPower Devices,
for details on board layout considerations.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or 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.
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Tel: 781.329.4700
Fax: 781.461.3113
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