19-3482; Rev 0; 10/04
KIT
ATION
EVALU
BLE
AVAILA
HD/SD Switchable Video Filters and Buffers
General Description
The MAX7454/MAX7455 triple-channel video recon-
struction filters and buffers are ideal for high definition
(HD), standard definition progressive scan/noninter-
laced (SDp), and standard definition interlaced (SDi)
television applications. These devices are a fully inte-
grated solution for filtering and buffering HD and/or
SDp/SDi TV signals in component video output format
(Y P
B
P
R
or RGB). The MAX7454/MAX7455 are compati-
ble with the 1080i, 720p, 480p, and 480i scanning system
standards. In addition to having an HD/SD switchable
frequency response, the magnitude response can be
optimized by approximately 15% by a control input.
The input and output signals are DC-coupled to the
MAX7454/MAX7455, eliminating the large output AC-cou-
pling capacitors normally used. The MAX7454/MAX7455
output buffers drive a 2V
P-P
video signal into a standard
150Ω load. The MAX7454 has a gain of +6dB and the
MAX7455 has a gain of +12dB. Both devices are available
in a 20-pin TSSOP package and are fully specified over
the upper commercial (0°C to +85°C) temperature range.
Features
♦
30MHz High Definition (HD)/10MHz Standard
Definition (SD) Switchable Video Reconstruction
Filter
♦
15% Magnitude Response Adjustment
♦
Passband: -2.3dB at 30MHz
-0.40dB at 10MHz
-0.10dB at 5MHz
♦
Stopband: -55dB at 74MHz (HDTV)
-62dB at 27MHz (SDTV)
♦
Output Blank Level <1V for DC-Coupled Output
♦
+6dB Gain (MAX7454) or +12dB Gain (MAX7455)
♦
Direct Coupled Input, Zero Tilt
♦
Direct Coupled Output, No Large Output Capacitor
♦
Drives 2V
P-P
Signal in 150Ω Video Load
♦
Small 20-Pin TSSOP Package
♦
Single +5V Supply
MAX7454/MAX7455
Applications
Set-Top Boxes
Direct-Broadcast Satellite (DBS) Receiver
DVD Players
Hard-Disk Recorders
HDTV (LCD, PDP, DLP)
Professional Cameras
Pin Configuration appears at end of data sheet.
PART
MAX7454UUP
MAX7455UUP*
Ordering Information
TEMP
RANGE
PIN-PACKAGE
BUFFER
GAIN (dB)
+6
+6
+12
+12
0°C to +85°C 20 TSSOP-EP**
0°C to +85°C 20 TSSOP-EP**
MAX7454UUP+* 0°C to +85°C 20 TSSOP-EP**
MAX7455UUP+* 0°C to +85°C 20 TSSOP-EP**
+Indicates
lead-free packaging.
*Future
product—contact factory for availability.
**EP
= Exposed pad.
Typical Operating Circuit
+5V
V
CC
MAX7454/MAX7455
ENCODER
Y/R
D/A
IN1
SWITCHABLE
LOWPASS
FILTER
+6dB OR
+12dB
OUT1
75Ω
Z
O
= 75Ω
75Ω
2
D/A
Pb/G
IN2
SWITCHABLE
LOWPASS
FILTER
+6dB OR
+12dB
OUT2
75Ω
Z
O
= 75Ω
75Ω
2
D/A
Pr/B
IN3
SWITCHABLE
LOWPASS
FILTER
+6dB OR
+12dB
OUT3
75Ω
Z
O
= 75Ω
75Ω
FSEL
SD/HD
GND
________________________________________________________________
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.
HD/SD Switchable Video Filters and Buffers
MAX7454/MAX7455
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ..............................................................-0.3V to +6V
IN1, IN2, IN3 to GND..................................-0.3V to (V
CC
+ 0.3V)
OUT1, OUT2, OUT3 to GND ......................-0.3V to (V
CC
+ 0.3V)
SD/HD, FSEL to GND .................................-0.3V to (V
CC
+ 0.3V)
Continuous Power Dissipation (T
A
= +70°C)
20-Pin TSSOP (derate 21.7mW/°C above +70°C) .....1739.1mW
Maximum Current into IN1, IN2, IN3, SD/HD, FSEL .........±50mA
Operating Temperature Range
MAX745_UUP .....................................................0°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Junction Temperature ......................................................+150°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
LOAD
= 150Ω to GND, C
LOAD
= 0 to 20pF to GND, SD/HD
= GND, FSEL = V
CC
, T
A
= T
MIN
to T
MAX,
unless other-
wise noted. Typical values are at V
CC
= +5V and T
A
= +25°C.)
PARAMETERS
HD-Filter Passband Response
HD-Filter Stopband Attenuation
SD-Filter Passband Response
SD-Filter Stopband Attenuation
HD Group Delay Deviation
HD Group Delay Matching
∆t
G
t
G(MATCH)
SYMBOL
A
PB
A
SB
CONDITIONS
f = 100kHz to 26MHz, FSEL = GND
f = 100kHz to 26MHz, FSEL = V
CC
f = 100kHz to 30MHz, FSEL = V
CC
f = 74MHz, FSEL = GND
f = 10MHz, SD/HD = V
CC
, FSEL = V
CC
f = 27MHz, SD/HD = V
CC
, FSEL = GND
100kHz to 26MHz, relative to 100kHz;
FSEL = V
CC
Channel to channel, 100kHz to 2MHz;
FSEL = V
CC
100kHz to 5.75MHz, relative to 100kHz;
SD/HD = VCC, FSEL = V
CC
100kHz to 10MHz, relative to 100kHz;
SD/HD = V
CC
, FSEL = V
CC
Channel to channel, 100kHz to 500kHz;
FSEL = V
CC
Gain = +2V/V, V
OUT
= 2V
P-P
video signal
100kHz to 26MHz
5-step modulated staircase (Note 1)
5-step modulated staircase (Note 1)
Output signal (2V
P-P
) to RMS noise (100kHz
to 30MHz)
Deviations in a line with an 18µs, 100 IRE
bar (Note 2)
MAX7454, THD > -30dB, f
IN
= 4.43MHz
MAX7455, THD > -30dB, f
IN
= 4.43MHz
MAX7454, V
IN
= 0.3V,
FSEL = GND
V
DIST
SD/HD = V
CC
SD/HD = GND
0
0
-0.25
-0.25
±1
62
MIN
-3.5
-2.6
-3.6
45
-0.65
50
TYP
-2.5
-1.7
-2.3
55
-0.40
62
5
0.1
2
ns
12
2
-45
0.3
0.2
67
±1
±3
1.2
0.6
+0.25
+0.25
±10
ns
dB
%
Degrees
dB
mV
V
mV
mV
dB
dB
dB
ns
ns
dB
MAX
UNITS
SD Group Delay Deviation
∆t
G
SD Group Delay Matching
Total Harmonic Distortion
Differential Gain
Differential Phase
Signal-to-Noise Ratio
Line Time Distortion
Input Voltage Range
Total Output DC Variation
Field Time Distortion
t
G(MATCH)
THD
dG
dθ
SNR
H
DIST
130 lines, 18µs, 100 IRE bars
2
_______________________________________________________________________________________
HD/SD Switchable Video Filters and Buffers
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V ±5%, R
LOAD
= 150Ω to GND, C
LOAD
= 0 to 20pF to GND, SD/HD = GND, FSEL = V
CC
, T
A
= T
MIN
to T
MAX,
unless other-
wise noted. Typical values are at V
CC
= +5V and T
A
= +25°C.)
PARAMETERS
Input Leakage Current
Input Capacitance
Low-Frequency Gain Accuracy
Low-Frequency Gain Matching
Dynamic Output Swing
Channel-to-Channel Isolation
Power-Supply Rejection Ratio
Supply Voltage Range
Supply Current
LOGIC INPUTS (SD/HD, FSEL)
Input High Voltage
Input Low Voltage
Input Current
V
IH
V
IL
Digital inputs = V
CC
or 0V
2.4
0.8
±10
V
V
µA
PSRR
V
CC
I
CC
No load
SYMBOL
IIN
CIN
f
IN
= 100kHz
f
IN
= 100kHz, maximum difference between
any two input channels
THD > -30dB
DC to 1MHz
V
IN
= 100mV
P-P
at 5MHz
V
IN
=10mV
P-P
at 26MHz
4.75
2.4
70
35
25
5
220
5.25
235
-2.5
0
CONDITIONS
MIN
TYP
±10
5
+2.5
1.2
MAX
UNITS
nA
pF
%
%
V
P-P
dB
dB
V
mA
MAX7454/MAX7455
Note 1:
The differential gain and differential phase specifications apply to standard-definition composite video signals only.
Note 2:
This applies for an anti-aliasing filtering application using a 0.1µF input capacitor. This does not apply for a video recon-
struction application, since there is no input-coupling capacitor.
Typical Operating Characteristics
(R
LOAD
= 150Ω to GND, V
CC
= +5V, and T
A
= +25°C.)
MAGNITUDE RESPONSE
(PASSBAND PLUS STOPBAND)
MAX7454toc01
GROUP DELAY
90
80
70
DELAY (ns)
MAX7454 toc02
10
0
-10
RESPONSE (dB)
-20
HDHI
-30
-40
-50
-60
-70
-80
0.1
1
10
FREQUENCY (MHz)
100
SDLO
HDLO
SDHI
100
60
50
40
30
20
10
HDHI
SDHI
1000
0
0.1
1
10
100
FREQUENCY (MHz)
_______________________________________________________________________________________
3
HD/SD Switchable Video Filters and Buffers
MAX7454/MAX7455
Typical Operating Characteristics (continued)
(R
LOAD
= 150Ω to GND, V
CC
= +5V, and T
A
= +25°C.)
2T RESPONSE (1 IRE = 7.14mV)
MAX7454 toc03
MODULATED 12.5T RESPONSE
(1 IRE = 7.14mV)
MAX7454 toc04
200mV/div
200mV/div
200mV/div
200mV/div
200ns/div
400ns/div
DIFFERENTIAL GAIN (%)
SUPPLY CURRENT vs. TEMPERATURE
MAX7454 toc05
DIFFERENTIAL GAIN
0.1
0
-0.1
-0.2
1
0.2
0.1
0
-0.1
-0.2
1
2
3
4
5
6
7
2
3
4
5
6
7
MAX7454 toc06
0.30
0.28
0.26
SUPPLY CURRENT (A)
0.24
0.22
0.20
0.18
0.16
0.14
0.12
0.10
-40
-15
10
35
60
HDLO
SDLO
HDHI
0.2
85
TEMPERATURE (°C)
4
_______________________________________________________________________________________
DIFFERENTIAL PHASE (deg)
DIFFERENTIAL PHASE
HD/SD Switchable Video Filters and Buffers
Pin Description
PIN
1, 3, 5, 7, 11,
12, 15, 18
2
4
6
8
9
10, 13, 16,
19
14
17
20
—
NAME
GND
IN1
IN2
IN3
SD/HD
FSEL
V
CC
OUT3
OUT2
OUT1
EP
Ground
Video Input 1
Video Input 2
Video Input 3
SD/HD Select. Selects between HD or SD magnitude response. Connect to GND to choose HD
bandwidth response.
Frequency Select. Selects either a low or high setting for both HD and SD frequency response (see
the
Frequency Adjusting
section).
+5V Power Supply. Bypass to GND with a 0.1µF capacitor. See the
Power-Supply Bypassing and
Layout Considerations
section.
Video Output 3
Video Output 2
Video Output 1
Exposed Pad. The exposed pad is internally connected to ground.
FUNCTION
MAX7454/MAX7455
Detailed Description
The MAX7454/MAX7455 are ideal for use in consumer
electronic products such as HD-compatible cable-TV
set-top boxes or DBS receiver decoders, which process
video signals in component output format. The
MAX7454/MAX7455 support both the 1080i and the
720p scanning formats for HDTV as well as the 480i and
480p formats for SDi and SDp TV. The reconstruction fil-
ters take three signals out of a video digital-to-analog
converter (DAC) or an encoder and smooth the signals
with appropriate filtering. FSEL and SD/HD select the fil-
ter frequency response for SDp, SDi, and HDTV (see
Table 1). The outputs are connected directly to standard
150Ω video loads.
The
Typical Operating Circuit
illustrates the internal
structure of the MAX7454/MAX7455. The lowpass filter
attenuates the high-frequency contents of the input,
and the output amplifier drives a standard video load.
Table 1. Frequency Selection Control
MODE
HD Low
HD High
SD Low
SD High
SD/HD
GND
GND
V
CC
V
CC
FSEL
GND
V
CC
GND
V
CC
frequencies of 74MHz and above for HDTV (see the
Typical Operating Characteristics).
Frequency Adjusting
SD/HD selects the HD or SD mode. In HD or SD mode,
FSEL allows optimization of the passband or stopband
performance by adjusting the cutoff frequency. If pass-
band performance is the priority, set FSEL high for the
maximum passband performance with a small compro-
mise in stopband attenuation. If stopband performance
is more important, set FSEL low for the maximum stop-
band attenuation with a small compromise in passband.
Due to the steep transition band response, the
MAX7454/MAX7455 can be used in both progressive
scan and interlaced video signals. The stopband atten-
uation at 27MHz or higher is >62dB.
Filter
Filter response
The video filter features an elliptic-type response with a
steep transition band response to achieve a wider
passband response along with an excellent stopband
response. In addition, the filter has been optimized to
give a good time domain response with low overshoot.
The stopband offers 62dB (typ) of attenuation at
sampling frequencies of 27MHz and above for
SDTV and 55dB (typ) of stopband attenuation for
Output Buffer
The output buffer on the MAX7454/MAX7455 drives a
2V
P-P
signal into a 150Ω video load. It is intended to be
DC-coupled per the digital TV standard. No output AC-
_______________________________________________________________________________________
5
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