19-2750; Rev 0; 1/03
6-Channel Integrated Video Reconstruction
Filters
General Description
The MAX7440/MAX7441/MAX7442 six-channel video
reconstruction filters replace 30 or more discrete com-
ponents. The devices are ideal for digital-to-analog
converter (DAC) video reconstruction applications,
when analog video is reconstructed from a digital data
stream. The MAX7440/MAX7441/MAX7442 operate
from a single +5V power supply. The inputs are DC-
coupled from the DAC and the output can either be AC-
or DC-coupled. The DC-IN, DC-OUT architecture, leads
to a perfect line-time distortion performance (zero tilt).
The filters have a cutoff frequency optimized for PAL,
NTSC, and SDTV video applications and offer three
high-frequency boost options. The MAX7440 offers a
flat passband response on all six channels; the
MAX7441/MAX7442 offer high-frequency boost on the
three channels used for CVBS and Y/C. The MAX7440/
MAX7441/MAX7442 are available in a 14-pin SO pack-
age and are fully specified over the extended tempera-
ture range.
Features
o
Replace 30 or More Discrete Components
o
Ideal for CVBS, Y/C (S-Video), and RGB or Y Pb Pr
Applications
o
45dB Attenuation at 27MHz
o
-0.2dB Passband Response
o
Ideal for STBs with SCART Interface
o
+5V Single-Supply Voltage
o
Input Common-Mode Range Includes GND
o
DC-Coupled Input, DC/AC-Coupled Output
o
14-Pin SO Package
MAX7440/MAX7441/MAX7442
Ordering Information
PART
MAX7440ESD
MAX7441ESD
PIN-
TEMP RANGE
PACKAGE
-40°C to +85°C 14 SO
-40°C to +85°C 14 SO
HIGH-
FREQUENCY
BOOST
No
Yes
Yes
Applications
STB
DVDs
Hard Disk Recorders
PVR
SCART Video Applications
General Video Filtering
+5V
MAX7442ESD*
-40°C to +85°C 14 SO
*Future product—contact factory for availability.
Typical Application Circuit
0.1µF
ENCODER
1µF
MAX7440
MAX7441
MAX7442
IN1
LOWPASS FILTER
WITH HF BOOST*
A = +1V/V
OUT1
A/V SWITCHING
DEVICE (MAX4399)
OR BUFFERS
75Ω
75Ω
D/A
D/A
IN2
LOWPASS FILTER
A = +1V/V
OUT2
75Ω
75Ω
D/A
IN3
LOWPASS FILTER
A = +1V/V
OUT3
75Ω
75Ω
D/A
IN4
LOWPASS FILTER
A = +1V/V
OUT4
75Ω
75Ω
D/A
IN5
LOWPASS FILTER
WITH HF BOOST*
A = +1V/V
OUT5
75Ω
75Ω
D/A
IN6
LOWPASS FILTER
WITH HF BOOST*
A = +1V/V
OUT6
75Ω
75Ω
*MAX7440 HAS FLAT RESPONSE, MAX7441/MAX7442 INCLUDES HF BOOST.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
6-Channel Integrated Video Reconstruction
Filters
MAX7440/MAX7441/MAX7442
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ...........................................................................+6V
All Other Pins to GND.................................-0.3V to (V
CC
+ 0.3V)
Maximum Current into Any Pin .........................................±50mA
Continuous Power Dissipation (T
A
= +70°C)
14-Pin SO (derate 8.3mW/°C above +70°C)..............666.7mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature ......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
CC
= +5V ±5%, R
L
= 5kΩ, C
L
= 0 to 20pF, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
SYMBOL
CONDITIONS
DC to 3.5MHz, MAX7440/MAX7441
(channels 2, 3, 4)
Passband Response
DC to 5MHz, MAX7440/MAX7441
(channels 2, 3, 4)
Stopband Attenuation
A
sb
f = 27MHz
+1dB HF boost,
MAX7441
Boost Amplitude
f = 4.5MHz
+2dB HF boost,
MAX7442
Differential Gain
Differential Phase
Signal-to-Noise Ratio
dG
dB
SNR
5-step modulated staircase
5-step modulated staircase
Peak signal (1V
P-P
) to RMS noise, f = 10Hz
to 100MHz
Low-frequency
channel-to-channel
matching,
f = 200kHz
Channels 2, 3, 4
Channels 1, 5, 6
MAX7440/MAX7441/
MAX7442
Group Delay Deviation
∆
g
Deviation from
100kHz to 4.5MHz
MAX7441 (channels
1, 5, 6)
MAX7442 (channels
1, 5, 6)
Line-Time Distortion
Field-Time Distortion
Low-Frequency Gain Variation
Low-Frequency Gain
Low-Frequency Gain Matching
Input Voltage Range
Channel-to-Channel Crosstalk
Input Leakage Current
X
TALK
I
IN
Channel-to-channel crosstalk, DC to 5MHz
V
IN
= 0V
2
t
g
f = 100kHz
-3
0
71
6
25
H
dist
V
dist
A
V
18µs, 100IRE bar
130 lines, 18µs, 100IRE bar
Gain at f = 100kHz
-3
-4
-0.25
0.975
+3
1.75
1.2
0.05
0.05
71
2
ns
2
10
17
17
0
+3
+4
+0.25
mV
mV
dB
V/V
%
V
dB
µA
ns
%
Degrees
dB
-0.80
37
0.4
-0.5
45
0.60
0.91
dB
0
dB
MIN
-0.40
TYP
-0.2
MAX
+0.10
dB
UNITS
Group Delay Matching
t
g(MATCH)
2
_______________________________________________________________________________________
6-Channel Integrated Video Reconstruction
Filters
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V ±5%, R
L
= 5kΩ, C
L
= 0 to 20pF, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
Input Resistance
Input Capacitance
Supply Voltage Range
Supply Current
Power-Supply Rejection Ratio
DC Level Shift
V
CC
I
CC
PSRR
V
CC
= +5.5V, no load
V
IN
= 100mV
P-P
OUT_ to IN_
DC
f = 0 to 1MHz
4.75
57
39
30
0.85
1.05
SYMBOL
CONDITIONS
MIN
200
20
5.25
78
TYP
MAX
UNITS
kΩ
pF
V
mA
dB
V
MAX7440/MAX7441/MAX7442
Typical Operating Characteristics
(V
CC
= +5V, R
L
= 5kΩ, T
A
= +25°C, unless otherwise noted.)
AMPLITUDE vs. FREQUENCY
MAX7440 toc01
PASSBAND AMPLITUDE vs. FREQUENCY
MAX7440 toc02
PHASE RESPONSE vs. FREQUENCY
150
100
MAX7440 toc03
0
-10
-20
AMPLITUDE (dB)
2
0
AMPLITUDE (dB)
-2
-4
-6
-8
-10
200
PHASE (DEGREES)
1
FREQUENCY (MHz)
50
0
-50
-100
-150
-200
-30
-40
-50
-60
-70
0.1
1
10
100
FREQUENCY (MHz)
0.1
10
0.1
1
FREQUENCY (MHz)
10
GROUP DELAY vs. FREQUENCY
MAX7441
(CHANNELS 2, 3, 4)
70
GROUP DELAY (ns)
MAX7440toc04
2T RESPONSE (1IRE = 7.14mV)
MAX7440 toc05
MODULATED 12.5T RESPONSE
(1IRE = 7.14mV)
MAX7440 toc06
80
IN_
200mV/div
IN_
200mV/div
60
OUT_
200mV/div
OUT_
200mV/div
50
40
0.1
1
FREQUENCY (MHz)
10
200ns/div
400ns/div
_______________________________________________________________________________________
3
6-Channel Integrated Video Reconstruction
Filters
MAX7440/MAX7441/MAX7442
Typical Operating Characteristics (continued)
(V
CC
= +5V, R
L
= 5kΩ, T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT
vs. TEMPERATURE
MAX7440 toc07
DIFFERENTIAL GAIN
DIFFERENTIAL GAIN (%)
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
1
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
1
2
3
4
5
6
7
2
3
4
5
6
7
MAX7440 toc08
SIGNAL SWING vs. LOAD
4.0
SIGNAL SWING (V
P-P
)
3.5
3.0
2.5
2.0
1.5
1.0
0.5
200
1000
1800
2600
LOAD (Ω)
3400
4200
5000
MAX7440 toc09
62
60
SUPPLY CURRENT (mA)
58
56
54
52
50
-40
-15
10
35
60
4.5
DIFFERENTIAL PHASE
DIFFERENTIAL PHASE
(DEGREES)
85
TEMPERATURE (°C)
CHANNEL-TO-CHANNEL CROSSTALK
vs. FREQUENCY
MAX7440toc10
GROUP DELAY MATCHING DISTRIBUTION
MAX7440 toc11
INPUT/OUTPUT LEVEL SHIFT
vs. TEMPERATURE
MAX7440 toc12
-65
50
20 SAMPLES
PERCENTAGE OF UNITS (%)
40
950
-70
910
LEVEL SHIFT (mV)
AMPLITUDE (dB)
-75
30
870
-80
20
830
-85
10
790
-90
0.1
1
FREQUENCY (MHz)
10
0
1.8
1.9
2.0
2.1
2.2
2.3
2.4
2.5
GROUP DELAY (ns)
750
-40
-15
10
35
60
85
TEMPERATURE (°C)
MULTIBURST RESPONSE
MAX7440 toc13
OUT_
200mV/div
10µs/div
4
_______________________________________________________________________________________
6-Channel Integrated Video Reconstruction
Filters
Pin Description
PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
NAME
IN1
IN2
IN3
V
CC
IN4
IN5
IN6
OUT6
OUT5
OUT4
GND
OUT3
OUT2
OUT1
Channel 2 Filter Input
Channel 3 Filter Input
+5V Power Supply. Bypass to GND with a 0.1µF and 1µF capacitor.
Channel 4 Filter Input
Channel 5 Filter Input (Optional Boosted Channel)
Channel 6 Filter Input (Optional Boosted Channel)
Channel 6 Filter Output
Channel 5 Filter Output
Channel 4 Filter Output
Ground
Channel 3 Filter Output
Channel 2 Filter Output
Channel 1 Filter Output
FUNCTION
Channel 1 Filter Input (Optional Boosted Channel)
MAX7440/MAX7441/MAX7442
Detailed Description
The MAX7440/MAX7441/MAX7442 filter the outputs of
DAC encoder chipsets that process digital video infor-
mation in applications such as set-top boxes, hard disk
recorders, DVD players, DVD recorders, and digital
VCRs. These devices also filter and clean up analog
video signals by rejecting out-of-band noise. Each
channel in the MAX7440/MAX7441/MAX7442 includes
a 4th-order lowpass filter and a gain of +1V/V output
stage, as shown in the
Typical Application Circuit.
Output Stage
The output stages of the MAX7440/MAX7441/MAX7442
are designed to drive 1V
P-P
signals into high-imped-
ance (>5kΩ) loads. They require external buffers to
drive standard video cables. Most standard audio/
video switching devices include these buffers for STB
applications.
Applications Information
MAX7440/MAX7441/MAX7442 with an A/V
Switching Device
The MAX7440/MAX7441/MAX7442 are designed to
directly interface to an audio/video switching device
used in video applications (i.e., STBs) with SCART
interfaces (see
Typical Application Circuit).
The output
of the analog filters can drive the high-impedance load
of the switching device. The switching device provides
the buffering to drive standard 150Ω video loads.
Filter
Filter Response
Each channel of the reconstruction filter consists of a
4th-order Sallen-Key filter configured as two 2nd-order
stages. The filter features a maximally flat passband for
NTSC, PAL, and SDTV bandwidths. The stopband
offers typically 45dB of attenuation at sampling fre-
quencies of 27MHz and above (see
Typical Operating
Characteristics).
The filter exhibits a Butterworth-type
response resulting in excellent group delay deviation
performance.
High-Frequency Boost
The high-frequency (HF) boost compensates for signal
degradation and rolloff in the signal path prior to the fil-
ter. This performance increases the image sharpness.
The MAX7441/MAX7442 offer a high-frequency boost
on channels OUT1, OUT5, and OUT6.
MAX7440/MAX7441/MAX7442 with
External Buffers
External buffering is required for the MAX7440/
MAX7441/MAX7442 to drive standard 150Ω video
loads. Figure 1 shows the MAX4394 triple op amp, con-
figured with a gain of +2V/V to drive standard video
loads from the MAX7440/MAX7441/MAX7442.
_______________________________________________________________________________________
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