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Bidirectional Video Filters/Buffers for Composite
and S-Video Portable Media Devices
General Description
The MAX7481/MAX7482 bidirectional video filters/
buffers provide the reconstruction filter and line drive
buffer for both composite (CVBS) and S-Video (Y/C)
video signals in playback mode, and anti-aliasing in
record mode for portable media devices. Each channel
consists of a lowpass filter and an output buffer capa-
ble of driving a full 2V
P-P
video signal into one standard
150Ω load (DC-coupled to ground). In record mode,
the MAX7481/MAX7482 output buffers have a gain of
+6dB. In playback mode, the MAX7481 output buffers
have a gain of +6dB and the MAX7482 output buffers
have a gain of +7dB.
The MAX7481/MAX7482 feature DirectDrive™ by utilizing
an internal negative charge pump and regulator to main-
tain the output blanking level at ground, eliminating the
need for a negative supply voltage, a large output cou-
pling capacitor, or a sag correction configuration.
The MAX7481/MAX7482 operate from a single +2.7V to
+3.6V power supply. These devices are available in a
space-saving 28-pin TQFN package and operate over
the -40°C to +85°C extended temperature range.
Features
♦
Composite and S-Video, Video-Playback and Video-
Record Interface for Portable Video Devices
♦
Saves Space by Sharing Connectors in Portable
Devices
♦
DirectDrive
Eliminates Expensive AC-Coupling Capacitors
Blanking Level at Ground with Single Supply
♦
Composite and Y/C Signals
♦
Advanced Power-Down Modes for Extended
Battery Life
♦
Low Supply Current in Shutdown Mode, < 1µA (typ)
♦
Filter Response Ideal for NTSC and PAL
♦
+6dB (MAX7481) or +7dB (MAX7482) Gain
♦
+2.7V to +3.6V Single-Supply Operation
♦
Small, 28-Pin, TQFN Package (5mm x 5mm)
MAX7481/MAX7482
Ordering Information
PART
MAX7481ETI+
MAX7482ETI+
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
28 TQFN-EP*
28 TQFN-EP*
PKG
CODE
T2855-6
T2855-6
Applications
Portable Media Devices
Digital Camcorders
Digital Cameras
+Denotes
lead-free package.
*EP
= Exposed pad.
Pin Configuration appears at end of data sheet.
Simplified Block Diagram
VIDEO
ADC
OUT4
PLAYBACK SIGNAL FLOW
MAX7481
MAX7482
VIDEO
DAC
0V
IN1
LPF
OUT1
IN3
IN5
P/R
VIDEO
PROCESSOR
CVBSON
YCON
CONTROL
LOGIC
OUT3
0V
VIDEO
DAC
IN2
LPF
OUT2
0V
IN4
VIDEO
ADC
0V
OUT5
RECORD SIGNAL FLOW
________________________________________________________________
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.
Bidirectional Video Filters/Buffers for Composite
and S-Video Portable Media Devices
MAX7481/MAX7482
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ............................................................. -0.3V to +4V
IN1–IN5 to GND..........................................-0.3V to (V
CC
+ 0.3V)
OUT1–OUT5 to GND ....................................-1.8V to (V
CC
+ 0.3V)
OUT1–OUT5 to GND (Shutdown) .................-0.3V to (V
CC
+ 0.3V)
BIAS, SHDN,
P/R,
YCON, CVBSON
to GND....................................................-0.3V to (V
CC
+ 0.3V)
CPV
CC
to CPGND ....................................................-0.3V to +4V
C1P to GND............................................... -0.3V to (V
CC
+ 0.3V)
C1N to GND ............................................... (V
SS
- 0.3V) to +0.3V
CPGND to GND.....................................................-0.1V to +0.1V
CPV
SS
to V
SS
.........................................................-0.1V to +0.1V
V
SS
to GND........................................................... -3.6V to +0.3V
Continuous Current
IN1–IN5, BIAS, CVBSON, YCON, C1P, C1N................±50mA
Output Short-Circuit Current.............................................±90mA
Continuous Power Dissipation (T
A
= +70°C)
28-Pin TQFN (derate 21.3mW/°C above +70°C) .......1702mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +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
= CPV
CC
= +3.0V, T
A
= +25°C, C1 = C2 = 1µF, C3 = C4 = C5 = 0.1µF, load at OUT1–OUT5 = 150Ω to GND, R
BIAS
= 100kΩ to
GND, unless otherwise noted. See the
Functional Diagram/Typical Application Circuit.)
PARAMETER
Passband Flatness
Stopband Attenuation
Differential Gain Error
Differential Phase Error
Signal-to-Noise Ratio
dG
dP
SNR
SYMBOL
f = 27MHz
5-step modulated staircase
5-step modulated staircase
Peak signal (2V
P-P
) to RMS noise,
f = 100kHz to 4.2MHz
IN1, V
IN
= -0.10V to 0.92V
IN2, V
IN
= -0.09V to 0.92V
Input Dynamic Swing
V
RANGE
AC-coupled
Input Leakage Current
I
IN
MAX7481: All outputs
MAX7482: OUT4, OUT5
Low Frequency Gain
f = 100kHz
MAX7482: OUT1, OUT2,
OUT3
Output Black Level Variation
Clamp Settling Time
Group-Delay Deviation
Line-Time Distortion
Field-Time Distortion
Channel-to-Channel Crosstalk
T
CLAMP
T
G
H
DIST
V
DIST
X
TALK
OUT1, OUT2, OUT4
OUT3, OUT5
To 5% with a 100 IRE step
Deviation from 100kHz to 4.2MHz
Deviation in a line with an 18µs, 100 IRE
bar; 1 line = 63.5µs
Deviation in 130 lines with an 18µs, 100 IRE
bar
f = 100kHz to 4.2MHz
-60
300
4
0.3
0.5
6.5
7
7.5
±150
±200
mV
Lines
ns
%
%
dB
5.5
6
IN3
IN4
IN5
CONDITIONS
f = 100kHz to 4.2MHz
MIN
-1
35
0.2
0.3
72
1.15
0.83
1.15
0.90
1.15
10
6.5
dB
µA
V
P-P
TYP
MAX
+1
UNITS
dB
dB
%
Degrees
dB
2
_______________________________________________________________________________________
Bidirectional Video Filters/Buffers for Composite
and S-Video Portable Media Devices
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= CPV
CC
= +3.0V, T
A
= +25°C, C1 = C2 = 1µF, C3 = C4 = C5 = 0.1µF, load at OUT1–OUT5 = 150Ω to GND, R
BIAS
= 100kΩ to
GND, unless otherwise noted. See the
Functional Diagram/Typical Application Circuit.)
PARAMETER
Power-Supply Rejection Ratio
CHARGE PUMP
Switching Frequency
LOGIC SIGNALS (CVBSON,
P/R,
YCON)
Logic-Low Threshold
Logic-High Threshold
Logic Input Current
SUPPLY
Supply Voltage Range
V
CC
,
CPV
CC
CVBSON = YCON = GND
I
CC
= I
VCC
+
I
CPVCC
, no
load,
P/R
=
GND, playback
mode
CVBSON = V
CC
, YCON =
GND
CVBSON = GND, YCON
= V
CC
CVBSON = YCON = V
CC
Shutdown Supply Current
Bias Voltage
I
SHDN
V
BIAS
I
SHDN
= I
VCC
+ I
CPVCC
; SHDN = V
CC
,
P/R
=
GND, CVBSON = YCON = V
CC
2.7
9
19
28
40
1
1
3.6
18
33
mA
42
52
10
µA
V
V
V
IL
V
IH
I
IL
V
CC
= +2.7V to +3.6V
V
CC
= +2.7V to +3.6V
1.5
10
0.5
V
V
µA
250
kHz
SYMBOL
PSRR
CONDITIONS
V
CC
= +2.7V to +3.6V
MIN
50
TYP
MAX
UNITS
dB
MAX7481/MAX7482
Quiescent Supply Current
I
CC
_______________________________________________________________________________________
3
Bidirectional Video Filters/Buffers for Composite
and S-Video Portable Media Devices
MAX7481/MAX7482
Typical Operating Characteristics
(V
CC
= CPV
CC
= +3.0V, T
A
= +25°C, unless otherwise noted.)
MAX7481
FREQUENCY RESPONSE
MAX7481 toc01
MAX7482
FREQUENCY RESPONSE
MAX7481 toc02
MAX7481
PASSBAND FLATNESS
INPUT = 1V
P-P
2
OUTPUT AMPLITUDE (dB)
1
0
-1
-2
-3
MAX7481 toc03
20
INPUT = 1V
P-P
OUTPUT AMPLITUDE (dB)
0
20
INPUT = 1V
P-P
OUTPUT AMPLITUDE (dB)
0
3
-20
-20
-40
-40
-60
-60
-80
0.1
1
10
100
FREQUENCY (MHz)
-80
0.1
1
10
100
FREQUENCY (MHz)
0.1
1
FREQUENCY (MHz)
10
MAX7482
PASSBAND FLATNESS
MAX7481 toc04
MAX7481
GROUP-DELAY RESPONSE
MAX7481 toc05
MAX7482
GROUP-DELAY RESPONSE
INPUT = 1V
P-P
110
GROUP DELAY (ns)
100
90
80
70
60
MAX7481 toc06
4
INPUT = 1V
P-P
3
OUTPUT AMPLITUDE (dB)
2
1
0
-1
-2
0.1
1
FREQUENCY (MHz)
120
INPUT = 1V
P-P
110
GROUP DELAY (ns)
100
90
80
70
60
120
10
0.1
1
FREQUENCY (MHz)
10
0.1
1
FREQUENCY (MHz)
10
2T RESPONSE
MAX7481 toc07
12.5T RESPONSE
MAX7481 toc08
IN1
200mV/div
IN1
200mV/div
OUT1
200mV/div
OUT1
200mV/div
200ns/div
400ns/div
4
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