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Evaluation Board User Guide
UG-210
One Technology Way • P. O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Te l: 781.329.4700 • Fax: 781.461.3113 • www.analog.com
Evaluation Boards for the ADM2482E and ADM2487E Isolated RS-485 Transceivers
PLEASE SEE THE LAST PAGE FOR AN IMPORTANT
WARNING AND LEGAL TERMS AND CONDITIONS.
Rev. A | Page 1 of 12
FEATURES
Easy evaluation of the ADM2482E/ADM2487E
Isolated ground plane layout
Configurable as full duplex or half duplex
Evaluation of the ADM2482E at 16 Mbps
Evaluation of the ADM2487E at 500 kbps
ADM2482E/ADM2487E APPLICATIONS
Isolated RS-485/RS-422 interfaces
Process field bus (PROFIBUS) networks
Industrial field networks
Multipoint data transmission systems
EVALUATION KIT CONTENTS
EVAL-ADM2482EEB3Z, EVAL-ADM2487EEB3Z,
EVAL-ADM2482EEB5Z, or EVAL-ADM2487EEB5Z
GENERAL DESCRIPTION
The ADM2482E/ADM2487E evaluation boards allow the
ADM2482E/ADM2487E isolated RS-485 transceivers to be
quickly and easily evaluated. The evaluation board allows all of
the input and output functions to be exercised without the need
for external components.
The ADM2482E/ADM2487E feature an integrated transformer
driver that outputs a pair of square waves to an external trans-
former to provide isolated power. When the ADM2482E/
ADM2487E are powered by 3.3 V on the logic side (V
DD1
), a trans-
former, U3, is required with a turns ratio of 1:1.5 (DA2303-AL).
This ensures that there is enough headroom for the ADP3330
LDO to output a regulated 3.3 V output (EVAL-ADM2482EEB3Z
and EVAL-ADM2487EEB3Z).
When the ADM2482E/ADM2487E are powered by 5 V on the
logic side, a transformer, U3, is required with a turns ratio of 1:1
(GA3157-AL) to give a 5 V input for the ADP3330, which regu-
lates an output of 3.3 V output (EVAL-ADM2482EEB5Z and
EVAL-ADM2487EEB5Z).
FUNCTIONAL BLOCK DIAGRAM
09479-001
V
DD1
IN OUT
GND
SD
ADP3330
B
A
R
T
Z
Y
RE
D1
D2
ADM2482E/ADM2487E
OSC
+3.3V ISO
LDO
RECTIFIER
POWER
CONNECTOR
CENTER TAPPED
TRANSFORMER
LOGIC
CONNECTO
R
DE
TxD
RxD
V
DD1
GND
1
GND
2
GND
1
GND
2
GND
2
V
DD2
BUS
CONNECTO
R
GALVANIC ISOLATION
Figure 1.
