Datasheet

ADV7123
Rev. D | Page 20 of 24
ANALOG SIGNAL INTERCONNECT
For optimum performance, the analog outputs should each
have a source termination resistance to ground of 75  (doubly
terminated 75  configuration). This termination resistance
should be as close as possible to the ADV7123 to minimize
reflections.
Place the ADV7123 as close as possible to the output connec-
tors, thus minimizing noise pickup and reflections due to
impedance mismatch.
The video output signals should overlay the ground plane and
not the analog power plane, thereby maximizing the high
frequency power supply rejection.
Additional information on PCB design is available in the
AN-333 Application Note, Design and Layout of a Video
Graphics System for Reduced EMI, which is available from
Analog Devices at www.analog.com.
35
36
37
33
31
27
R9 TO R0
39 TO 48
COMP V
AA
V
AA
V
AA
V
AA
V
REF
R
SET
IOR
75Ω 75Ω
75Ω
COAXIAL CABLE
75Ω
POWER SUPPLY DECOUPLIN
G
(0.1µF AND 0.01µF CAPACITOR
FOR EACH V
AA
GROUP)
AD1580
ADV7123
MONITOR (CRT)
1
2
BNC
CONNECTORS
COMPLEMENTARY
OUTPUTS
75Ω
1kΩ
R
SET
530Ω
IOG
IOB
12
SYNC
11
BLANK
24
CLOCK
38
PSAVE
GND
25, 26
13, 29,
30
VIDEO
DATA
INPUTS
G9 TO G0
1TO 10
B9 TO B0
14 TO 23
IOR
IOG
IOB
75Ω
75Ω
32
28
34
0.1µF
0.1µF
1µF
0.01µF
00215-028
Figure 28. Typical Connection Diagram