Analog Devices EVAL-ADN4651EB1Z, Руководство пользователя

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UG-900 EVAL-ADN4651EB1Z/EVAL-ADN4652EB1Z User Guide
Rev. A | Page 6 of 13
RADIATED EMISSIONS TEST RESULTS (EN 55022)
GND1
GND1
GND2
GND2
V
DD2
V
DD1
V
IN1
V
IN2
P4
R1
R12 R11 R10
R2
R4 R8
R5
R3
R7
R6
R9
J9
J1
J2
J3
J4
J5
J6
J7
J8
J10
J22 J21
J24 J23
U1
P7
EVAL-ADN4651EB1Z
2 × AA BATTERY
3V TO 3.15V
2 × AA BATTERY
3V TO 3.15V
SIGNAL
GENERATOR
10m COAX CABLE ×2
NOTES
1. SIGNAL GENERATOR OUTSIDE TEST CHAMBER
2. INPUT SIGNAL: |V
ID
| = 300mV, V
IC
= 1.1V, 600MBPS PRBS7 OR 300MHz CLOCK
13761
-105
Figure 6. Test Setup for EN 55022 Radiated Emissions Testing for the EVAL-ADN4651EB1Z ; Scope and Signal Generator Reversed for the EVAL-ADN4652EB1Z
Radiated emissions testing is performed with the EVAL-
ADN4651EB1Z and EVAL-ADN4652EB1Z at an independent
external test facility. Evaluating the EVAL-ADN4651EB1Z and
EVAL-ADN4652EB1Z to the EN 55022 standard is undertaken in
a 10 m radiated emissions test chamber, using the test setup
shown in Figure 6. The setup comprises a battery-powered
EVAL-ADN4651EB1Z / EVAL-ADN4652EB1Z connected to a
signal generator located outside the chamber via coax cables. As
specified by the EN 55022 standard, both horizontal and vertical
peak scans are undertaken with any visible emissions peaks
investigated using quasi-peak detector measurement. For each
frequency measured using a quasi-peak detector, the unit under
test rotates through 360 degrees to find the worst case angle. The
receiving antenna then elevates from 1 m to 4 m in height to find
the worst case elevation. The worst case quasi-peak measurements
are compared to the EN 55022 Class B and Class A limits.
The test results for EVAL-ADN4651EB1Z and EVAL-
ADN4652EB1Z are shown in Table 4 and a classification report
for both evaluation boards is available on request (please contact
Analog Devices or the distributor for support). Radiated emissions
are measured across 30 MHz to 1 GHz and from 1 GHz to 3 GHz.
With a 600 Mbps PRBS7 input, the EVAL-ADN4651EB1Z / EVAL-
ADN4652EB1Z passes the EN 55022 Class B limits. Plots for
horizontal and vertical peak radiated emissions below 1 GHz are
shown in Figure 7 and Figure 8, respectively, for the
EVAL-
ADN4651EB1Z ; see the classification report for the EVAL-
ADN4652EB1Z plots.
With a 300 MHz clock input, the EVAL-ADN4651EB1Z / EVAL-
ADN4652EB1Z passes the EN 55022 Class A limits. To pass the
Class B limits when isolating high frequency clocks, reduce the
printed circuit board (PCB) clearance from the 8 mm implemented
on the
EVAL-ADN4651EB1Z / EVAL-ADN4652EB1Z to, for
example, 2 mm.
Table 4. EN 55022 Radiated Emissions Classification
Test Condition Result
600 Mbps PRBS Passes EN 55022 Class B
300 MHz Clock Passes EN 55022 Class A