ADA4430-1 Analog Devices, ADA4430-1 Datasheet - Page 14

• Manufacturer Part Number: ADA4430-1
• Description: Ultralow Power Video Filter
• Manufacturer: Analog Devices

ADA4430-1
RECONSTRUCTION FILTER APPLICATIONS
Figure 33 illustrates how to use the ADA4430-1 as a dc-coupled
reconstruction filter with a pass band gain of 2 following the
low power
ADV7191
the remaining portions of the
The
The 2.4 kΩ resistor, R
output current to its minimum full-scale value of 2.16 mA, and
the 600 Ω load resistor produces a full-scale voltage of 1.296 V
at the ADA4430-1 input.
Figure 34 illustrates another reconstruction filter application,
following the
ADV7174
the remaining portions of the
ADV7190/ADV7191
output DAC is shown for illustrative purposes, and
output DAC is shown for illustrative purposes, and
ADV7190/ADV7191
ADV7174
SET
, shown in Figure 33 sets the DAC
video encoder. As in Figure 33, one
2.4kΩ
is operated in 4× oversampling mode.
ADV7190/ADV7191
V
R
V
AA
R
17, 25, 29, 38, 43, 54, 63
SET
AA
ADV7174 DAC
2, 10, 18, 25, 27
SET
ADV7190/ADV7191
ADV7174
48
31
1041Ω
(931Ω + 110Ω)
POWER-DOWN CONTROL
POWER-DOWN CONTROL
DAC
video encoder. One
AGND
Figure 33. Using the ADA4430-1 with the ADV7190/ADV7191 Video Encoder
AGND
18, 24, 26, 33,
39, 42, 55, 64
are omitted.
6-9, 11, 12,
17, 19, 26, 40
(191Ω + 71.5Ω)
Figure 34. Using the ADA4430-1 with the ADV7174 Video Encoder
262.5Ω
are omitted.
0.1µF
ADV7190/
600Ω
0.1µF
1
2
3
1
2
3
ADA4430-1
V
SAG
GND
ADA4430-1
V
GND
SAG
IN
Rev. A | Page 14 of 16
IN
×1
×1
2.6kΩ
2.6kΩ
2.6kΩ
2.6kΩ
The 1041 Ω resistor, R
output current to its minimum full-scale value of 5 mA, and the
262.5 Ω load resistor produces a full-scale voltage of 1.313 V at
the ADA4430-1 input.
The
current of approximately 35 mA and is therefore capable of
driving the video cable directly; however, as is shown in Figure 34,
the ADA4430-1 offers a lower, power cable-driving option.
Figure 34 reveals the details of how the ADA4430-1 saves
power when driving video cables with terminations at both
ends. A full-scale level at the DAC output produces 2.626 V at
the ADA4430-1 output, which in turn delivers 17.5 mA into
the cable. In the case shown in Figure 27, the output voltage is
1.313 V, but the current driven into the cable is 35 mA − twice
that required when the ADA4430-1 is used. Therefore, the
ADA4430-1 allows the video encoder to be operated at its
minimum full-scale output current, and it efficiently handles
the cable-driving burden.
1.3kΩ
1.3kΩ
PD
PD
ADV7174
5 6
5
3V
2.6kΩ
3V
2.6kΩ
V
V
6
V
S+
OUT
V
S+
OUT
0.1µF
0.1µF
4
4
can produce a maximum full-scale DAC output
75Ω
75Ω
75Ω CABLE
SET
75Ω CABLE
, shown in Figure 34, sets the DAC
75Ω
75Ω