adv7390 Analog Devices, Inc., adv7390 Datasheet - Page 63

• Manufacturer Part Number: adv7390
• Description: Low Power, Chip Scale 10-bit Sd/hd Video Encoder
• Manufacturer: Analog Devices, Inc.

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GROUP DELAY (Seconds)
GROUP DELAY (Seconds)
Figure 89. Output Filter Plot for SD, 16× Oversampling
Figure 91. Output Filter Plot for HD, 4× Oversampling
Figure 90. Output Filter Plot for ED, 8× Oversampling
GROUP DELAY (Seconds)
CIRCUIT FREQUENCY RESPONSE
CIRCUIT FREQUENCY RESPONSE
CIRCUIT FREQUENCY RESPONSE
10M
10M
FREQUENCY (Hz)
FREQUENCY (MHz)
FREQUENCY (Hz)
10
MAGNITUDE (dB)
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MAGNITUDE (dB)
MAGNITUDE (dB)
PHASE (Degrees)
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(Degrees)
PHASE
(Degrees)
PHASE
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1G
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Rev. 0 | Page 63 of 96
PRINTED CIRCUIT BOARD (PCB) LAYOUT
The ADV739x is a highly integrated circuit containing both
precision analog and high speed digital circuitry. It has been
designed to minimize interference effects on the integrity of the
analog circuitry by the high speed digital circuitry. It is imperative
that these same design and layout techniques be applied to the
system-level design so that optimal performance is achieved.
The layout should be optimized for lowest noise on the
ADV739x power and ground planes by shielding the digital
inputs and providing good power supply decoupling.
It is recommended to use a 4-layer printed circuit board with
ground and power planes separating the signal trace layer and
the solder side layer.
Component Placement
Component placement should be carefully considered to
separate noisy circuits, such as clock signals and high speed
digital circuitry from analog circuitry.
The external loop filter components and components connected
to the COMP and R
to and on the same side of the PCB as the ADV739x. Adding
vias to the PCB to get the components closer to the ADV739x is
not recommended.
It is recommended that the ADV739x be placed as close as
possible to the output connector, with the DAC output traces as
short as possible.
The termination resistors on the DAC output traces should be
placed as close as possible to and on the same side of the PCB as
the ADV739x. The termination resistors should overlay the
PCB ground plane.
External filter and buffer components connected to the DAC
outputs should be placed as close as possible to the ADV739x to
minimize the possibility of noise pickup from neighboring
circuitry, and to minimize the effect of trace capacitance on
output bandwidth. This is particularly important when
operating in low drive mode (R
Power Supplies
It is recommended that a separate regulated supply be provided
for each power domain (V
optimal performance, linear regulators rather than switch mode
regulators should be used. If switch mode regulators must be
used, care must be taken with regard to the quality of the output
voltage in terms of ripple and noise. This is particularly true for
the V
individually connected to the system power supply at a single
point through a suitable filtering device, such as a ferrite bead.
ADV7390/ADV7391/ADV7392/ADV7393
AA
and PV
DD
power domains. Each power supply should be
SET
pins should be placed as close as possible
AA
, V
DD
SET
, V
= 4.12 kΩ, R
DD_IO
, and PV
L
= 300 Ω).
DD
). For