En 55032 Radiated Emissions Test Results - Analog Devices EVAL-ADM2867EEBZ User Manual

EVAL-ADM2867EEBZ
To maximize the margin to the EN 55032 Class B specification,
adhere to the following guidelines:

Ensure that the decoupling capacitors are placed as close to
the corresponding ADM2867E

Place a 10 μF capacitor (C4) and a 0.1 μF capacitor (C5)
between the V pin and GND
CC

Place a 0.1 μF capacitor (C7) between the V
GND pins of the ADM2867E.
1

Connect Pin 24, Pin 26, and Pin 28 of the
together to form a single GND
GND pins through the E1 ferrite bead.
2

Place a 0.1 μF capacitor (C9) between the V
and the GND net of the ADM2867E.
ISO

Connect the V pin to the V
ISOOUT
through the E2 ferrite bead.

Place a 10 μF capacitor (C12) and a 0.1 μF capacitor (C8)
between the V supply pin (Pin 23) and the GND
ISOIN
(Pin 22) of the ADM2867E.

Remove any metal planes or floods from the area around
or under the GND net and V
ISO
The EVAL-ADM2867EEBZ designed according to these
guidelines meets the EN 55032 Class B requirements with
margin. See Figure 2, Figure 7, and Figure 8 for further details
on the recommended PCB layout.
Table 2. Jumper Configurations
Link Jumper Connection
LK1 A
B
C
LK2 A
B
C
D
LK3 AB
BC
Not inserted
LK4 A
B
C
User Guide
pins as possible.
pins of the ADM2867E.
1
pin and
IO
ADM2867E
net. Connect this net to the
ISO
supply pin
ISOOUT
pin of the ADM2867E
ISOIN
pins
2
net.
ISOOUT
Description
Connects the RE input of the ADM2867E
Connects the RE input of the
Connects the RE input of the ADM2867E
Connects the DE input of the
Connects the DE input of the
Connects the DE input of the
Connects the DE input of the
is set by the LK1 jumper. This setting ensures that when the driver is enabled, the receiver is disabled, or
when the driver is disabled, the receiver is enabled.
Connects the TxD input of the
Connects the TxD input of the
To configure the oscillator frequency to be between 1 kHz and 12.5 MHz, set the R2 and R3 resistors.
Only use this option when the V
Connects the TxD input of the
Connects the INVD input of the
Connects the INVD input of the
Connects the INVD input of the
Rev. 0 | Page 5 of 12
10µF
0.1µF
0.1µF
Figure 2. Layout Guidelines to Achieve EN 55032 Class B

EN 55032 RADIATED EMISSIONS TEST RESULTS

The EVAL-ADM2867EEBZ meets the EN 55032 and CISPR32
Class B requirements for radiated emissions with margin. The
testing was performed in worst case conditions under a full
54 Ω load with both the transceiver and receiver transmitting
at 25 Mbps. Figure 3 shows the results obtained in a 10 meter,
semianechoic chamber, which are below the Class B limit.
80
70
60
50
40
30
20
10
0
30
Figure 3. CISPR32/EN 55032 Radiated Emissions Test
to the V pin. This setting disables the receiver.
IO
ADM2867E to the RE terminal on the P2 connector.
to the GND pins. This setting enables the receiver.
1
ADM2867E to the V pin. This setting enables the driver.
IO
ADM2867E to the DE terminal on the P2 connector.
ADM2867E to the GND pins. This setting disables the driver.
1
ADM2867E to the RE input signal. Therefore, the input for both RE and DE
ADM2867E and J1 SMA connector to the TxD terminal on the P3 connector.
ADM2867E and J1 SMA connector to the
supply input is between 3 V to 5.5 V.
IO
ADM2867E to the J1 SMA connector.
ADM2867E to the V pin. This setting enables the driver inversion feature.
IO
ADM2867E to the INVD terminal on the P3 connector.
ADM2867E to the GND pins. This setting is used for normal driver operation.
1
METAL KEEP OUT
GND
GND
1 ISO
1
28
GND
V
1 SEL
2
27
GND
GND
1
ISO
3
26
V V
ISOOUT
CC
4
25
GND GND
1 ISO
5
24
GND V
1 ISOIN
6
23
V ADM2867E GND
IO 2
7
22
TOP VIEW
RxD GND
2
8
(Not to Scale) 21
RE A
9
20
DE
B
10
19
TxD Z
11
18
INVD Y
12
17
GND
INVR
2
13
16
GND
GND
1 2
14
15
100
FREQUENCY (MHz)
LTC6900 oscillator output.
UG-1677
E1 10µF
0.1µF
E2
0.1µF
CLASS A
CLASS B
1000