Datenblatt für ADA4430-1 von Analog Devices Inc.

ANALOG DEVICES with Power-Down ADA4430-1 C}.j E J j 3% E j
Ultralow Power Video Filter
with Power-Down
ADA4430-1
Rev. C
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
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Tel: 781.329.4700 www.analog.com
Fax: 781.461.3113 ©2006–2010 Analog Devices, Inc. All rights reserved.
FEATURES
Qualified for automotive applications
6th-order performance, low-pass video filter
1 dB flatness out to 8 MHz
50 dB rejection at 27 MHz
Ultralow power-down current: 0.1 μA typical
Low quiescent current: 1.85 mA typical
Excellent video specification
Differential gain: 0.25%
Differential phase: 0.10°
SAG correction
Allows use of small capacitors in ac-coupled outputs
Low supply voltage: 2.5 V to 6 V
Rail-to-rail output
High input-to-output isolation in disabled state
92 dB at 1 MHz
Low input bias current: 0.5 μA
Small packaging: SC70 and SOT-23 (automotive grade only)
Wide operating temperature range: −40°C to +125°C
APPLICATIONS
Automotive infotainment (SOT-23 only)
Automotive rearview cameras (SOT-23 only)
Portable media players
Portable gaming consoles
Cell phones
Digital still cameras
Portable DVD players
Portable video cameras
PIN CONFIGURATION
2 × R
2 × R 2 × R
×1
R
1
2
3
6
5
4
V
S
V
OUT
V
IN
GND
SAG
DIS
05885-001
ADA4430-1
Figure 1.
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
11
GAIN (dB)
FREQUENCY (MHz)
05885-006
0
V
S
= 3V
V
S
= 5V
Figure 2. Frequency Response Flatness at Various Power Supplies
GENERAL DESCRIPTION
The ADA4430-1 is a fully integrated video reconstruction filter
that combines excellent video specifications with low power
consumption and an ultralow power disable, making it ideal
for portable video filtering applications. With 1 dB frequency
flatness out to 8 MHz and 50 dB rejection at 27 MHz, the
ADA4430-1 is ideal in SD video applications, including
NTSC and PAL.
The ADA4430-1 operates on single supplies as low as 2.5 V and
as high as 6 V while providing the dynamic range required by
the most demanding video systems.
The ADA4430-1 also provides an on-chip dc offset to avoid
clipping of the sync tips at the filter output, as well as SAG
correction that permits smaller capacitor values to be used in
applications with ac-coupled outputs.
The ADA4430-1 is available in a two 6-lead packages. The SC70
for commercial applications and the SOT-23 for automotive
applications are rated to work in the extended temperature
range of −40°C to +125°C.
ADA4430-1
Rev. C | Page 2 of 20
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Pin Configuration ............................................................................. 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 5
Thermal Resistance ...................................................................... 5
ESD Caution .................................................................................. 5
Pin Configuration and Function Descriptions ............................. 6
Typical Performance Characteristics ............................................. 7
Test Circuits ..................................................................................... 11
Theory of Operation ...................................................................... 12
Overview ..................................................................................... 12
Power Savings Using the ADA4430-1 ..................................... 12
Applications Information .............................................................. 13
Examples Illustrating Output Coupling .................................. 13
Usable Input Voltage Range ...................................................... 14
SAG Correction Frequency Response ..................................... 14
Reconstruction Filter Applications .......................................... 15
Printed Circuit Board Layout ................................................... 16
Outline Dimensions ....................................................................... 17
Ordering Guide .......................................................................... 18
Automotive Products ................................................................. 18
REVISION HISTORY
9/10—Rev. B to Rev. C
Change Automotive Products Section Heading ......................... 18
6/10—Rev. A to Rev. B
Updated Pin Name PD to DIS Throughout .................................. 1
Added 6-Lead SOT-23 ....................................................... Universal
Changes to Features Section, General Description Section,
Applications Section, and Figure 1 ................................................. 1
Changes to Table 1 ............................................................................ 3
Changes to Table 2 ............................................................................ 4
Changes to Table 4, Maximum Power Dissipation Section, and
Figure 3 .............................................................................................. 5
Changes to Figure 4 and Table 5 ..................................................... 6
Changes to Figure 16 ........................................................................ 8
Changes to Figure 25 and Figure 26............................................. 11
Changes to Overview Section ....................................................... 12
Changes to Figure 29, Figure 30, and Figure 31 ......................... 13
Changes to Figure 33 and Figure 34............................................. 15
Added Figure 36; Renumbered Sequentially .............................. 17
Updated Outline Dimensions ....................................................... 17
Changes to Ordering Guide .......................................................... 18
Added Automotive Products Section .......................................... 18
6/06—Rev. 0 to Rev. A
Changes to Figure 1 ........................................................................... 1
Changes to Figure 4 ........................................................................... 5
3/06—Revision 0: Initial Version
ADA4430-1
Rev. C | Page 3 of 20
SPECIFICATIONS
VS = 3 V @ TA = 25°C, VIN = 1 V p-p, RL = 150 Ω, unless otherwise noted.
Table 1.
Parameter Test Conditions/Comments Min Typ Max Unit
ELECTRICAL SPECIFICATIONS
Quiescent Supply Current 1.85 2.3 mA
Quiescent Supply Current ADA4430-1W only: TMIN to TMAX 1.85 3 mA
Quiescent Supply Current—Disabled 0.1 5 μA
Quiescent Supply Current—Disabled ADA4430-1W only: TMIN to TMAX 0.1 6 μA
Supply Voltage ADA4430-1W only: TMIN to TMAX 2.5 6 V
Input Voltage Range—Low/High Limited by output range; see the Applications Information
section
0/1.38 V
Input Resistance 10
Input Capacitance 1 pF
Input Bias Current 0.5 μA
Output Voltage Range—Low/High 0.10/2.85 V
Output Offset Voltage 95 140 mV
Output Offset Voltage ADA4430-1W only: TMIN to TMAX 95 200 mV
PSRR Input referred, ADA4430-1W only: TMIN to TMAX 50 60 dB
Pass-Band Gain ADA4430-1W only: TMIN to TMAX 5.85 6 dB
Input-to-Output Isolation—Disabled f = 1 MHz 92 dB
FILTER CHARACTERISTICS
−3 dB Bandwidth ADA4430-1W only: TMIN to TMAX 7 9.7 MHz
1 dB Flatness ADA4430-1W only: TMIN to TMAX 5.5 8.0 MHz
Out-of-Band Rejection f = 27 MHz; ADA4430-1W only: TMIN to TMAX 40 50 dB
Differential Gain Modulated 10-step ramp, sync tip at 0 V 0.25 %
Differential Phase Modulated 10-step ramp, sync tip at 0 V 0.10 Degrees
Linear Output Current 40 mA
Group Delay Variation f = 100 kHz to 5 MHz 7 ns
Signal-to-Noise Ratio 100% white signal, f = 100 kHz to 5 MHz 76 dB
DISABLE
Disable Input Voltage Device disabled <0.7 V
Device enabled >1.1 V
ADA4430-1
Rev. C | Page 4 of 20
VS = 5 V @ TA = 25°C, VIN = 1 V p-p, RL = 150 Ω, unless otherwise noted.
Table 2.
Parameter Test Conditions/Comments Min Typ Max Unit
ELECTRICAL SPECIFICATIONS
Quiescent Supply Current 2.0 2.4 mA
Quiescent Supply Current ADA4430-1W only: TMIN to TMAX 2.0 3.1 mA
Quiescent Supply Current—Disabled 0.2 10 μA
Quiescent Supply Current—Disabled ADA4430-1W only: TMIN to TMAX 0.2 15 μA
Supply Voltage ADA4430-1W only: TMIN to TMAX 2.5 6 V
Input Voltage Range—Low/High Limited by output range; see the Applications
Information section
0/2.35 V
Input Resistance 10
Input Capacitance 1 pF
Input Bias Current 0.5 μA
Output Voltage Range—Low/High 0.10/4.80 V
Output Offset Voltage 100 145 mV
Output Offset Voltage ADA4430-1W only: TMIN to TMAX 100 200 mV
PSRR Input referred, ADA4430-1W only: TMIN to TMAX 50 61 dB
Pass-Band Gain ADA4430-1W only: TMIN to TMAX 5.85 6 dB
Input-to-Output Isolation—Disabled f = 1 MHz 92 dB
FILTER CHARACTERISTICS
−3 dB Bandwidth ADA4430-1W only: TMIN to TMAX 7.2 9.5 MHz
1 dB Flatness ADA4430-1W only: TMIN to TMAX 5.5 7.9 MHz
Out-of-Band Rejection f = 27 MHz, ADA4430-1W only: TMIN to TMAX 40 50 dB
Differential Gain Modulated 10-step ramp, sync tip at 0 V 0.25 %
Differential Phase Modulated 10-step ramp, sync tip at 0 V 0.15 Degrees
Linear Output Current 40 mA
Group Delay Variation f = 100 kHz to 5 MHz 7.1 ns
Signal-to-Noise Ratio 100% white signal, f = 100 kHz to 5 MHz 76 dB
DISABLE
Disable Input Voltage Device disabled <0.8 V
Device enabled >1 V
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ADA4430-1
Rev. C | Page 5 of 20
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter Rating
Supply Voltage 6 V
Power Dissipation See Figure 3
Storage Temperature Range −65°C to +125°C
Operating Temperature Range −40°C to +125°C
Lead Temperature (Soldering 10 sec) 300°C
Junction Temperature 150°C
The power dissipated in the package (PD) is the sum of the
quiescent power dissipation and the power dissipated in the
package due to the load drive. The quiescent power is the
voltage between the supply pins (VS) times the quiescent
current (IS). The power dissipated due to the load drive depends
upon the particular application. The power due to load drive is
calculated by multiplying the load current by the associated
voltage drop across the device. RMS voltages and currents must
be used in these calculations.
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Airflow increases heat dissipation, effectively reducing θJA. In
addition, more metal directly in contact with the package leads
from metal traces, through holes, ground, and power planes
reduces the θJA.
Figure 3 shows the maximum safe power dissipation in the
package vs. the ambient temperature for the 6-lead SC70
(430°C/W) and the 6-lead SOT-23 (170°C/W) on a JEDEC
standard 4-layer board.
THERMAL RESISTANCE
θJA is specified for the worst-case conditions, that is, θJA is
specified for a device soldered in the circuit board.
05885-002
1.2
1.0
0.8
0.6
0.4
0.2
0
–40 120100806040020–20
MAXIMUM POWER DISSIPATION (W)
AMBIENT TEMPERATURE (°C)
SOT-23
SC70
Table 4. Thermal Resistance
Package Type θJA Unit
6-Lead SC70 430 °C/W
6-Lead SOT-23 170 °C/W
Maximum Power Dissipation
The maximum safe power dissipation in the ADA4430-1
package is limited by the associated rise in junction temperature
(TJ) on the die. At approximately 150°C, which is the glass
transition temperature, the plastic changes its properties. Even
temporarily exceeding this temperature limit can change the
stresses that the package exerts on the die, permanently shifting
the parametric performance of the ADA4430-1. Exceeding a
junction temperature of 150°C for an extended period can
result in changes in the silicon devices, potentially causing
failure.
Figure 3. Maximum Power Dissipation vs. Temperature for a 4-Layer Board
ESD CAUTION
|_||—\|—| V AX! UULI E m
ADA4430-1
Rev. C | Page 6 of 20
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
2 × R
2 × R 2 × R
×1
R
1
2
3
6
5
4
V
S
V
OUT
V
IN
GND
SAG
DIS
05885-041
ADA4430-1
Figure 4. 6-Lead SC70 and SOT23 Top View
Table 5. Pin Function Descriptions
Pin Number Mnemonic Description
1 VIN Input Voltage.
2 GND Ground.
3 SAG Feedback Connection.
4 VOUT Output Voltage.
5 DIS Disable.
6 VS Positive Power Supply.
ADA4430-1
Rev. C | Page 7 of 20
TYPICAL PERFORMANCE CHARACTERISTICS
VS = 3 V, RL, = 150 Ω, VOUT = 2.0 V p-p, DIS = high, VOUT connected directly to SAG, TA = 25°C, unless otherwise noted.
9
–48
–45
–42
–39
–36
–33
–30
–27
–24
–21
–18
–15
–12
–9
–6
–3
0
3
6
110010
GAIN (dB)
FREQUENCY (MHz)
05885-003
V
S
= 5V
V
S
= 3V
Figure 5. Frequency Response at Various Power Supplies
9
–48
–45
–42
–39
–36
–33
–30
–27
–24
–21
–18
–15
–12
–9
–6
–3
0
3
6
110010
GAIN (dB)
FREQUENCY (MHz)
05885-004
R
L
= 150
R
L
= 75
Figure 6. Frequency Response at Various Loads
9
–48
–45
–42
–39
–36
–33
–30
–27
–24
–21
–18
–15
–12
–9
–6
–3
0
3
6
110010
GAIN (dB)
FREQUENCY (MHz)
05885-005
+125°C
+25°C
–40°C
Figure 7. Frequency Response at Various Temperatures
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
11
GAIN (dB)
FREQUENCY (MHz)
05885-006
0
V
S
= 3V
V
S
= 5V
Figure 8. Frequency Response Flatness at Various Power Supplies
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
GAIN (dB)
FREQUENCY (MHz)
05885-007
R
L
= 75
110
R
L
= 150
Figure 9. Frequency Response Flatness at Various Loads
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
GAIN (dB)
FREQUENCY (MHz)
05885-008
+125°C
+25°C
–40°C
110
Figure 10. Frequency Response Flatness at Various Temperatures
ADA4430-1
Rev. C | Page 8 of 20
9
–48
–45
–42
–39
–36
–33
–30
–27
–24
–21
–18
–15
–12
–9
–6
–3
0
3
6
110010
GAIN (dB)
FREQUENCY (MHz)
05885-009
0.2V p-p
2.0V p-p
Figure 11. Frequency Response at Various Output Amplitudes
50
–150
–145
–140
–135
–130
–125
–120
–115
–110
–105
–100
–95
–90
–85
–80
–75
–70
–65
–60
–55
1065432
(dB)
FREQUENCY (MHz)
05885-010
NOISE SPECTRUM (NTSC)
INPUT REFERRED
BANDWIDTH 100kHz TO 5.0MHz
AMPLITUDE (0dB = 714mV p-p)
NOISE LEVEL = –76.8dB rms
Figure 12. Input-Referred Noise Spectral Density
40
–130
–120
–110
–100
–90
–80
–70
–60
–50
0.01 1001010.1
ISOLATION (dB)
FREQUENCY (MHz)
05885-011
V
IN
= 1V p-p
V
DIS
= 0V
OUTPUT REFERRED
Figure 13. Input-to-Output Isolation—Disabled vs. Frequency
65
60
55
50
45
40
35
30
1110
GROUP DELAY (ns)
FREQUENCY (MHz)
05885-012
00
V
S
= 3V
V
S
= 5V
Figure 14. Group Delay at Various Power Supplies
0
–5
–10
–15
–20
–25
–30
–35
–40
–45
–50
–55
–60
–65
0.001 0.01 1001010.1
PSRR (dB)
FREQUENCY (MHz)
05885-013
5V
3V
INPUT REFERRED
Figure 15. PSRR vs. Frequency at Various Power Supplies
10
100
1000
10000
0.1 1 10 100 500
V
DIS
=0V
05885-030
FREQUENCY (MHz)
IMPEDANCE ()
Figure 16. Disabled Output Impedance vs. Frequency
ADA4430-1
Rev. C | Page 9 of 20
3.0
2.5
2.0
1.5
1.0
0.5
0
OUTPUT VOLTAGE (V)
05885-015
100ns/DIV
Figure 17. Transient Response
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5
OUTPUT VOLTAGE (V)
05885-016
DISABLEDISABLE
OUTPUT
1µs/DIV
Figure 18. Disable Assert Time
–1.0
–0.5
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
OUTPUT
INPUT
05885-033
OUTPUT (V)
200ns/DIV
Figure 19. Overdrive Recovery
3.00
2.75
2.50
2.25
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
OUTPUT VOLTAGE (V)
ERROR (%)
05885-018
ERROR
INPUT × 2
OUTPUT
50ns/DIV
Figure 20. Settling Time
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5
OUTPUT VOLTAGE (V)
500ns/DIV
05885-019
DISABLE
OUTPUT
Figure 21. Disable Deassert Time
–0.20
–0.19
–0.18
–0.17
–0.16
–0.15
–0.14
–0.13
–0.12
–0.11
0.10
4025105 203550658095110125
05885-031
TEMPERATURE (°C)
DIFFERENCE BETWEEN V
S
AND V
OUT
(V)
Figure 22. Output Swing Limits vs. Temperature
ADA4430-1
Rev. C | Page 10 of 20
1.85
1.80
1.75
1.70
1.65
400
300
200
100
0
120100806040200–20–40
POWER SUPPLY CURRENT–ENABLED (mA)
POWER SUPPLY CURRENT–DISABLED (nA)
TEMPERATURE (°C)
05885-021
DISABLED (V
DIS
= 0V)
ENABLED (V
DIS
= 3V)
2.0
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
3.02.52.01.51.00.50
POWER SUPPLY CURRENT (mA)
DISABLE VOLTAGE (V)
05885-022
+125°C
+25°C
–40°C
Figure 23. Power Supply Current vs. Temperature
Figure 24. Power Supply Current vs. Disable Voltage at Various Temperatures
ADA4430-1
Rev. C | Page 11 of 20
TEST CIRCUITS
2.6k
2.6k
2.6k
1.3k
SAG
GND
V
IN
V
OUT
DIS V
S
ADA4430-1
1
2
3
4
56
118
R
L
= 150
5086.6
0.1µF
TEST GENERATOR
V
S+
05885-038
50
50
TEST RECEIVER
0.5V
×1
Figure 25. Test Circuit Used for Frequency Sweeps and Time-Domain Tests
2.6k
2.6k
2.6k
1.3k
SAG
GND
V
IN
V
OUT
ADA4430-1
1
2
3
4
56
75
R
L
= 150
75
0.1µF
TEST GENERATO
R
DIS V
S
V
S+
05885-039
75150
150
TEST RECEIVER
1.0V
220µF
×1
Figure 26. Test Circuit Used for Differential Gain, Differential Phase, and Noise Tests
,,,,,,,,
ADA4430-1
Rev. C | Page 12 of 20
THEORY OF OPERATION
OVERVIEW The internal buffer at the ADA4430-1 input isolates the source
resistance feeding the ADA4430-1 from the internal filter networks.
High input impedance is also advantageous when using video
clamping circuits.
The ADA4430-1 is designed for exceptional performance as
both a filter and a low power driver for portable video applica-
tions. This performance is achieved by providing high order
filtering without trading off power consumption or device size.
While consuming only 1.85 mA quiescent supply current, the
ADA4430-1 provides video output on a single-supply as low as
2.5 V. Such low power consumption and low supply operation
normally indicates a single op amp with a two- or three-pole
roll-off; however, the ADA4430-1 achieves a sixth-order roll-off
in addition to a 10 MΩ input impedance for easy clamping and
lower DAC output power requirements. When not in use, the
ADA44330-1 can be shut down to draw less than 0.1 µA of supply
current using the disable pin (DIS). Additionally, the ADA4430-
1 is unique in that it is a high order filter that fits into an SC70
package.
The output buffer feedback network used to create a gain of 2 is
connected internally to the GND pin and has a nominal impedance
of 5.2 k. The current required to drive this feedback network
causes the overall supply current to vary based on the output
level. The feedback impedance was chosen specifically to
minimize excess current consumption while maintaining
optimal frequency behavior.
POWER SAVINGS USING THE ADA4430-1
Using a series source termination and a shunt load termination
on a low supply voltage with the ADA4430-1 realizes significant
power savings compared with driving a video cable directly from
a DAC output. Figure 27 shows a video DAC driving a cable
directly. Properly terminating the line results in the DAC driving
two 75 Ω loads and requires in excess of 30 mA to reach a full-
scale level of 1.3 V. Figure 28 shows the same video load being
driven using the ADA4430-1 and a series-shunt termination. This
requires two times the output voltage to drive the equivalent of
150 Ω but only requires a little more than 15 mA to reach a full-
scale output. When running on the same supply voltage as the
DAC, this results in nearly a factor of two reduction in power
compared with the circuit in Figure 27. The high level of
filtering provided by the ADA4430-1 lowers the requirements
on the DAC oversampling ratio, realizing further power savings.
On any given DAC, 8× and 16× oversampling ratios can require
twice the power consumption of a 4× oversampling ratio.
The ADA4430-1 provides a minimum 1 dB bandwidth of
5.5 MHz and a typical stop-band rejection of 50 dB at 27 MHz.
Phase response is not sacrificed in spite of the exceptional
filtering performance of the ADA4430-1, as exhibited by its
group delay, which varies by only 7 ns from 100 kHz to 5 MHz.
The ADA4430-1 is intended for use in applications that have
both ac- and dc-coupled inputs and outputs. The rail-to-rail
buffer on the ADA4430-1 output is able to drive 2 V p-p video
signals into two doubly terminated video loads (150 Ω each) on
a single 2.5 V supply. The ADA4430-1 has a gain of 2 when the
SAG correction pin is tied directly to the output, which makes
up for the 6 dB termination loss. When the SAG feature is used
(see Figure 29), the ADA4430-1 has a low frequency gain of
2.5 ( 8 dB) and a high frequency gain of 2. Signal offsets and
supply levels must be considered when using the SAG correction
feature to ensure that there are no headroom issues.
3
V
VIDEO
DAC/
ENCODER 75
75
05885-034
The input range of the ADA4430-1 includes ground, while the
output range is limited by the saturation of the output devices.
Saturation occurs several tens of mV from the positive and
negative supply rails. For accurate reproduction of ground-
referenced input signals, an internal offset is used to shift the
output up by 95 mV.
Figure 27. DAC Driving Video Cable Directly
0.1µF
3
V
R
L
VIDEO
DAC/
ENCODER
ADA4430-1
FILTER
G = +2 75
75
05885-035
The high input impedance and low input capacitance of the
ADA4430-1 offer advantages in a number of low power
applications. In reconstruction filter applications, the DAC can
be placed in its lowest power mode, allowing the use of a large-
valued load resistor. Using a large-valued load resistor does not
interfere with the frequency response of the ADA4430-1.
Figure 28. DAC Driving Video Cable Using the ADA4430-1
:v ADA441304 ADA4430-1 <10 ada114304="">
ADA4430-1
Rev. C | Page 13 of 20
APPLICATIONS INFORMATION
EXAMPLES ILLUSTRATING OUTPUT COUPLING
The ADA4430-1 is ideally suited for use as a reconstruction
filter that follows a video DAC or encoder. The application
circuits in Figure 29, Figure 30, and Figure 31 illustrate a
number of ways the ADA4430-1 can be used with a single-
supply current-output DAC on its input and its output ac- and
dc-coupled.
SAG correction allows the use of two small, lower cost
capacitors in place of one large capacitor in applications with
ac-coupled outputs. Circuits with ac-coupled outputs consume
less power than those with dc-coupled outputs.
2.6k
2.6k2.6k
1.3k
SAG
GND
V
IN
V
OUT
R
L
VIDEO OUT
DIS
V
S
3V
DISABLE CONTROL
0.1µF
ADA4430-1
1
2
3
4
56
VIDEO
DAC/ENCODER
05885-027
75
47µF
22µF
×1
Figure 29. AC-Coupled Output with SAG Correction
2.6k
2.6k2.6k
1.3k
SAG
GND
V
IN
V
OUT
R
L
VIDEO OUT
3V
DISABLE CONTROL 0.1µF
ADA4430-1
1
2
3
4
56
VIDEO
DAC/ENCODER
0
5885-028
75
220µF
DIS V
S
×1
Figure 30. Traditional AC-Coupled Output with 220 μF Coupling Capacitor
2.6k
2.6k2.6k
1.3k
SAG
GND
V
IN
V
OUT
R
L
V
IDEO OU
T
3
DISABLE CONTROL 0.1µF
ADA4430-1
1
2
3
4
56
VIDEO
DAC/ENCODER
05885-029
75
DIS V
S
×1
Figure 31. DC-Coupled Output
ADA4430-1
Rev. C | Page 14 of 20
USABLE INPUT VOLTAGE RANGE
The output voltage range of the ADA4430-1 limits its usable
input voltage range. The lower end of the input range is
typically 0 V. The upper end of the usable input voltage
range is calculated as
VIN (max) = (VOMVOO)/2
where:
VIN (max) is the upper end of the usable input voltage range.
VOM is the maximum output swing.
VOO is the output-referred offset voltage.
SAG CORRECTION FREQUENCY RESPONSE
When using the SAG corrected circuit, the gain from the input
to the immediate output of the ADA4430-1 is ×2.5 (8 dB) at
extremely low frequencies where the outer feedback loop
formed by the 22 µF capacitor effectively opens (see Figure 29)
and exhibits a second-order peak of approximately 11 dB at
about 5 Hz. This gain is approximately 7.5 dB at 30 Hz. The
extra gain must be accounted for when considering low
frequency input and output signal swings to keep them within
their specified limits. The gain from the ADA4430-1 input to
the load side of the 47 µF capacitor does not exhibit this
behavior; rather, it appears more like a single-pole high-
pass response. Figure 32 illustrates the SAG frequency response
immediately at the ADA4430-1 output and at the load side of the
47 µF capacitor.
12
10
8
6
4
2
0
–2
–4
–6
–8
–10 1 10 100 1000 10000010000
05885-040
GAIN (dB)
FREQUENCY (Hz)
AT ADA4430-1 OUTPUT
AT LOAD SIDE OF 47µF CAPACITOR
Figure 32. SAG Corrected Frequency Response at ADA4430-1 Output and
at the Load Side of the 47 μF Capacitor
ADA4430-1
Rev. C | Page 15 of 20
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 ADV7190/ADV7191 video encoder. One ADV7190/
ADV7191 output DAC is shown for illustrative purposes, and
the remaining portions of the ADV7190/ADV7191 are omitted.
The ADV7190/ADV7191 is operated in 4× oversampling mode.
The 2.4 kΩ resistor, RSET, shown in Figure 33 sets the DAC
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 video encoder. As in Figure 33, one
ADV7174 output DAC is shown for illustrative purposes, and
the remaining portions of the ADV7174 are omitted.
The 1041 Ω resistor, RSET, shown in Figure 34, sets the DAC
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 ADV7174 can produce a maximum full-scale DAC output
current of approximately 35 mA and is therefore capable of
driving the video cable directly; however, as 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.
2.6k
2.6k
2.6k
1.3k
SAG
GND
V
IN
V
OUT
ADV7190/ADV7191
DAC
DIS V
S
DISABLE CONTROL
ADA4430-1
1
2
3
4
56
2.4k
600
75
75
75 CABLE
0.1µF
0.1µF
R
SET
17, 25, 29, 38, 43, 54, 63
34, 48 18, 24, 26, 33,
39, 42, 55, 64
AGND
V
AA
3V
05885-036
×1
Figure 33. Using the ADA4430-1 with the ADV7190/ADV7191 Video Encoder
2.6k2.6k
1.3k
SAG
GND
V
IN
V
OUT
ADV7174 DAC
V
S
DISABLE CONTROL
ADA4430-1
1
2
3
4
56
1041
(931 + 110)
75
75
75 CABLE
0.1µF
0.1µF
R
SET
2, 10, 18, 25, 27
31
6-9, 11, 12,
17, 19, 26, 40
AGND
V
AA
3
V
05885-037
262.5
(191 + 71.5)
2.6k
DIS
×1
Figure 34. Using the ADA4430-1 with the ADV7174 Video Encoder
ADA4430-1
Rev. C | Page 16 of 20
PRINTED CIRCUIT BOARD LAYOUT
As with all high speed applications, attention to printed circuit
board layout is of paramount importance. Standard high speed
layout practices should be adhered to when designing with the
ADA4430-1. A solid ground plane is recommended, and a 0.1 µF
surface-mount, ceramic power supply, decoupling capacitor should
be placed as close as possible to the supply pin.
The GND pin should be connected to the ground plane with a
trace that is as short as possible. Controlled impedance traces of
the shortest length possible should be used to connect to the signal
I/O pins and should not pass over any voids in the ground plane. A
75 Ω impedance level is typically used in video applications. All
signal outputs of the ADA4430-1 should include series termination
resistors when driving transmission lines.
When the ADA4430-1 receives its inputs from a device with
current outputs, the required load resistor value for the output
current is most often different from the characteristic impedance of
the signal traces. In this case, if the interconnections are sufficiently
short (less than 2 inches), the trace does not have to be
terminated in its characteristic impedance.
ADA4430-1
Rev. C | Page 17 of 20
OUTLINE DIMENSIONS
1.30 BSC
COMPLIANT TO JEDEC STANDARDS MO-203-AB
1.00
0.90
0.70
0.46
0.36
0.26
2.20
2.00
1.80
2.40
2.10
1.80
1.35
1.25
1.15
072809-A
0.10 MAX
1.10
0.80
0.40
0.10
0.22
0.08
312
46 5
0.65 BSC
COPLANARITY
0.10
SEATING
PLANE
0.30
0.15
Figure 35. 6-Lead Thin Shrink Small Outline Transistor Package [SC70]
(KS-6)
Dimensions shown in millimeters
COMPLIANT TO JEDEC STANDARDS MO-178-AB
121608-A
10°
SEATING
PLANE
1.90
BSC
0.95 BSC
0.60
BSC
65
123
4
3.00
2.90
2.80
3.00
2.80
2.60
1.70
1.60
1.50
1.30
1.15
0.90
0
.15 MAX
0
.05 MIN
1.45 MAX
0.95 MIN
0.20 MAX
0.08 MIN
0.50 MAX
0.30 MIN
0.55
0.45
0.35
PIN 1
INDICATOR
Figure 36. 6-Lead Small Outline Transistor Package [SOT-23]
(RJ-6)
Dimensions shown in millimeters
ADA4430-1
Rev. C | Page 18 of 20
ORDERING GUIDE
Model1, 2 Temperature Range Package Description Package Option Branding Ordering Quantity
ADA4430-1YKSZ-R2 −40°C to +125°C 6-Lead SC70 KS-6 H0G 250
ADA4430-1YKSZ-R7 −40°C to +125°C 6-Lead SC70 KS-6 H0G 3,000
ADA4430-1YKSZ-RL −40°C to +125°C 6-Lead SC70 KS-6 H0G 10,000
ADA4430-1WYRTZ-R7 −40°C to +125°C 6-Lead SOT-23 RJ-6 H25 3,000
1 Z = RoHS-Compliant Part.
2 W = Qualified for Automotive Applications.
AUTOMOTIVE PRODUCTS
The ADA4430-1W model is available with controlled manufacturing to support the quality and reliability requirements of automotive
applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers
should review the Specifications section of this data sheet carefully. Only the automotive grade products shown are available for use in
automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to
obtain the specific Automotive Reliability reports for these models.
ADA4430-1
Rev. C | Page 19 of 20
NOTES
ANALOG DEVICES www.analng.cnm
ADA4430-1
Rev. C | Page 20 of 20
NOTES
©2006–2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D05885-0-9/10(C)