19-0531; Rev 2; 1/09
KIT
ATION
EVALU
E
L
B
A
IL
AVA
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
The MAX9508 video filter amplifier with SmartSleep and
bidirectional video support is ideal for set-top boxes
(STBs), portable DVD players, and portable media
players (PMPs). The inputs can be directly connected
to the digital-to-analog converter (DAC) outputs. The
reconstruction filter removes high-frequency signals
above 6.75MHz. The amplifiers have 6dB of gain, and
the outputs can be DC-coupled to a load of 75Ω,
which is equivalent to two video loads, or it can be
AC-coupled to a load of 150Ω.
The SmartSleep circuitry intelligently reduces power
consumption based on the presence of the input signal
and the output loads. When the MAX9508 does not
detect the presence of sync on the input video signal,
the supply current is reduced to less than 7µA. The
device only enables a video amplifier when there is an
active video input signal and an attached load. The
video amplifier remains on while a load is connected. If
the load is disconnected, the video amplifier is turned off.
The MAX9508 contains three reconstruction filters, four
video amplifiers, and a pulldown switch at one of the
two CVBS outputs. The MAX9508 has the ability to control the bidirectional video signals at the CVBS video
connections without the need for separate switches or
relays. This feature is particularly useful for portable
DVD players, which often use the same connector to
drive a composite video output and to accept an external video signal to display on the LCD panel.
The MAX9508 operates from a 2.7V to 3.6V single supply
and is offered in a small 16-pin TQFN (3mm x 3mm)
package. The device is specified over the -40°C to
+125°C automotive temperature range.
Applications
Features
♦ SmartSleep Feature Detects Input Signal and
Output Load Status to Reduce Power
Consumption
♦ Triple Standard-Definition Video Reconstruction
Filters with 6.75MHz Passband
♦ Luma, Chroma, and Composite Inputs
♦ Luma, Chroma, and Two Composite Outputs
♦ Integrated Support for a Bidirectional Composite
Video Signal
♦ Supports Two Video Loads at Each Output
(DC-Coupled)
♦ 2.7V to 3.6V Single-Supply Operation
Ordering Information
PART
PIN-PACKAGE
TOP MARK
16 TQFN-EP*
(3mm x 3mm)
AEM
MAX9508ATE+
Note: Device is specified over the -40°C to +125°C operating
temperature range.
+Denotes lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Block Diagrams
LOAD SENSE
BUFFER
CIN
LOAD SENSE
BUFFER
YIN
YOUT
6dB
LPF
Portable DVD Players
COUT
6dB
LPF
INT/EXT
Set-Top Boxes (STBs)
Portable Set-Top Boxes/
Personal Video Recorders (PVRs)
SMARTSLEEP
MAX9508
LOAD SENSE
ACTIVE VIDEO
DETECT
Portable Media Players (PMPs)
Portable Applications
CONTROL
LOGIC
SHDN
CVBSOUT1
6dB
CVBSIN
BUFFER
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
6dB
Pin Configurations appear at end of data sheet.
CVBSOUT2
Block Diagrams continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
MAX9508
General Description
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
ABSOLUTE MAXIMUM RATINGS
(Voltages with respect to GND.)
VDD ..........................................................................-0.3V to +4V
SMARTSLEEP, SHDN, INT/EXT
CIN, YIN, CVBSIN, EXTCVBSIN ..........................-0.3V to +4V
Duration of COUT, YOUT, CVBSOUT1, CVBSOUT2
Short Circuit to VDD or GND ..................................Continuous
Continuous Input Current
CIN, YIN, EXTCVBSIN, CVBSIN,
SMARTSLEEP, SHDN, INT/EXT ....................................±20mA
Continuous Power Dissipation (TA = +70°C)
16-Pin TQFN (derate 15.6mW/°C above +70°C)..........1250mW
Operating Temperature Range .........................-40°C to +125°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
(VDD = VSHDN = 3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V, RL = No load. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Supply Voltage Range
Supply Current
VDD
IDD
CONDITIONS
Guaranteed by PSRR
MIN
ISHDN
MAX
UNITS
3.6
V
INT/EXT = GND (4 channels active),
YIN = CVBSIN = 0.3V, CIN = 0.6V
13
INT/EXT = VDD (1 channel active),
EXTCVBSIN is unconnected
4.3
6
SMARTSLEEP = VDD,
CVBSIN has no active video signal
7
14
16
mA
µA
SMARTSLEEP = VDD, CVBSIN has a blackburst video signal with sync tip at GND
(Note 2)
Shutdown Supply Current
TYP
2.7
17
VSHDN = GND
0.01
10
µA
5.2
% VDD
200
Ω
SMARTSLEEP CHARACTERISTICS
Minimum Line Frequency
CVBSIN
14.3
Sync Slice Level
CVBSIN
4.1
Output Load Detect Threshold
Sync pulse present, RL to GND
kHz
DC CHARACTERISTICS
Input-Voltage Range
VIN
CIN, YIN, CVBSIN,
guaranteed by output
voltage swing
2.7V < VDD < 3.6V
0
1.05
3.0V < VDD < 3.6V
0
1.2
V
Input Current
IIN
CIN = YIN = CVBSIN = 0V
2
Input Resistance
RIN
CIN, YIN, CVBSIN
20
2
_______________________________________________________________________________________
5
µA
MΩ
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
(VDD = VSHDN = 3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V, RL = No load. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Sync-Tip Clamp Level
SYMBOL
VCLP
CONDITIONS
MIN
EXTCVBSIN
0.25
Input Clamping Current
EXTCVBSIN = 500mV + VCLP
0.5
EXTCVBSIN Input Voltage Range
Guaranteed by
output voltage
swing
Output Resistance
2
%
Ω
300
RL = 150Ω to VDD/2, 0V ≤ VIN ≤ 1.05V,
VDD = 2.7V
5.7
6
6.3
dB
RL = 150Ω to VDD/2, 0V ≤ VIN ≤ 1.05V,
VDD = 2.7V
-0.2
0
+0.2
dB
YIN = CVBSIN = CIN = 0V,
INT/EXT = GND, RL = 150Ω to GND
0.21
0.3
0.38
CEXTCVBSIN = 0.1µF to GND,
INT/EXT = VDD, RL = 150Ω to GND
0.21
0.27
0.38
TA = -40°C to
+85°C
2.027
2.1
2.163
TA = -40°C to
+125°C
2.006
Measured at output, VDD = 2.7V,
0V ≤ VIN ≤ 1.05V, RL = 150Ω to VDD / 2
2.027
2.1
2.163
TA = -40°C to
+85°C
2.316
2.4
2.472
TA = -40°C to
+125°C
2.292
Measured at output,
VDD = 3V,
0V ≤ VIN ≤ 1.2V,
RL = 150Ω to -0.2V
ROUT
µA
VP-P
Measured at output,
VDD = 2.7V,
0V ≤ VIN ≤ 1.05V,
RL = 150Ω to -0.2V
Output Voltage Swing
1.5
1.2
EXTCVBSIN
Output Level
V
3.0V < VDD < 3.6V
Maximum Input Source
Resistance
DC Gain Matching
UNITS
0.37
1.05
Sync Crush
AV
1
MAX
2.7V < VDD < 3.6V
EXTCVBSIN, percentage reduction in sync
pulse (0.3VP-P), guaranteed by input
clamping current measurement, measured
at input
DC Voltage Gain
TYP
V
2.163
2.472
Measured at output, VDD = 3V,
0V ≤ VIN ≤ 1.2V, RL = 150Ω to VDD / 2
2.316
2.4
2.472
Measured at output, VDD = 3.135V,
0V ≤ VIN ≤ 1.05V, RL = 75Ω to -0.2V
2.027
2.1
2.163
VOUT = 1.3V, -5mA ≤ ILOAD ≤ +5mA
VP-P
0.47
Ω
_______________________________________________________________________________________
3
MAX9508
ELECTRICAL CHARACTERISTICS (continued)
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
ELECTRICAL CHARACTERISTICS (continued)
(VDD = VSHDN = 3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V, RL = No load. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Power-Supply Rejection Ratio
Output Pulldown Resistance
PSRR
RPD
CONDITIONS
2.7V ≤ VDD ≤ 3.6V, input referred,
RL = 150Ω to GND
MIN
TYP
MAX
48
UNITS
dB
INT/EXT = VDD, CVBSOUT1
Output Shutdown Impedance
3.7
Ω
28
kΩ
LOGIC INPUTS (SMARTSLEEP, SHDN, INT/EXT)
Logic-Low Threshold
VIL
Logic-High Threshold
VIH
Logic Input Current
IIL / IIH
0.3 x
VDD
0.7 x
VDD
VI = 0V or VDD
V
V
0.01
10
µA
AC ELECTRICAL CHARACTERISTICS
(VDD = VSHDN = 3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V, RL = 150Ω to GND. TA = TMIN to TMAX, unless otherwise noted.
Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
f = 5.5MHz
Standard-Definition
Reconstruction Filter
Inputs are 1VP-P, reference
frequency is 1MHz.
f = 6.75MHz
Differential Gain
Differential Phase
MAX
UNITS
-0.1
-1
f = 11MHz
f = 27MHz
TYP
-0.3
-3
-33
+1
dB
-41
DC-coupled output,
5-step modulated staircase
f = 3.58MHz or
4.43MHz
0.2
AC-coupled output,
5-step modulated staircase
f = 3.58MHz or
4.43MHz
0.4
DC-coupled output,
5-step modulated staircase
f = 3.58MHz
0.62
f = 4.43MHz
0.75
AC-coupled output,
5-step modulated staircase
f = 3.58MHz
0.78
f = 4.43MHz
1.01
DG
%
DP
Degrees
2T Pulse Response
2T = 200ns or 250ns
0.2
K%
2T Bar Response
Bar time is 18µs, the beginning 2.5% and the ending 2.5%
of the bar time are ignored, 2T = 200ns or 250ns
0.2
K%
2T Pulse-to-Bar K
Rating
Bar time is 18µs, the beginning 2.5% and the ending 2.5%
of the bar time are ignored, 2T = 200ns or 250ns
0.3
K%
4
_______________________________________________________________________________________
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
(VDD = VSHDN = 3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V, RL = 150Ω to GND. TA = TMIN to TMAX, unless otherwise noted.
Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Nonlinearity
5-step staircase
0.1
%
Interchannel Timing
Error
Difference in time between the 50% point of the output
signals, YOUT to COUT
0.2
ns
Group Delay
Distortion
100kHz ≤ f ≤ 5MHz, inputs are 1VP-P
10
ns
Interchannel Group
Delay Distortion Error
Inputs are 1VP-P
2
ns
Peak Signal to RMS
Noise
100kHz ≤ f ≤ 5MHz, inputs are 1VP-P
67
dB
Power-Supply
Rejection Ratio
f = 100kHz, 200mVP-P, input referred
43
dB
Output Impedance
f = 5MHz
6
Ω
Enable Time
YIN = 1V, output settled to within 1% of the final voltage,
RL = 150Ω to GND
13
µs
Disable Time
YIN = 1V, output settled to within 1% of the final voltage,
RL = 150Ω to GND
1.1
µs
All Hostile Output
Crosstalk
f = 4.43MHz
-70
dB
All Hostile Input
Crosstalk
f = 4.43MHz, SHDN = GND,
input termination resistors are 75Ω
-69
dB
CROSSTALK
Note 1: All devices are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design.
Note 2: Specified current is an average over time.
_______________________________________________________________________________________
5
MAX9508
AC ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics
(VDD = VSHDN = +3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V. RL = 150Ω to GND. TA = +25°C, unless otherwise noted.)
SMALL-SIGNAL GAIN FLATNESS
vs. FREQUENCY
-10
-20
-30
-40
0.4
0.2
0
-0.2
-0.4
-0.6
-50
-1.0
100k
1M
-20
-30
-40
10M
100M
100k
1M
10M
100M
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
LARGE-SIGNAL GAIN FLATNESS
vs. FREQUENCY
GROUP DELAY
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
0.6
VOUT = 2VP-P
0
125
-10
-20
DELAY (ns)
0.2
0
-0.2
PSRR (dB)
100
0.4
MAX9508 toc06
VOUT = 2VP-P
NORMALIZED TO 1MHz
MAX9508 toc05
150
MAX9508 toc04
1.0
0.8
-10
-60
1M
100k
100M
10M
0
-50
-0.8
-60
75
50
-30
-40
-50
-0.4
25
-60
-0.6
0
-0.8
-70
-25
-1.0
100k
1M
10M
-80
100k
100M
1M
100M
10M
10k
100k
1M
10M
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
QUIESCENT SUPPLY CURRENT
vs. TEMPERATURE
VOLTAGE GAIN
vs. TEMPERATURE
OUTPUT VOLTAGE
vs. INPUT VOLTAGE
2.01
12.5
12.0
2.00
OUTPUT VOLTAGE (V)
13.0
3.5
YIN, CIN, CVBSIN
INPUTS ONLY
3.0
VOLTAGE GAIN (V/V)
13.5
4.0
MAX9508 toc08
2.02
MAX9508 toc07
14.0
1.99
1.98
1.97
100M
MAX9508 toc09
OUTPUT AMPLITUDE (dB)
0.6
VOUT = 2VP-P
NORMALIZED TO 1MHz
10
OUTPUT AMPLITUDE (dB)
OUTPUT AMPLITUDE (dB)
OUTPUT AMPLITUDE (dB)
0
VOUT = 100mVP-P
NORMALIZED TO 1MHz
0.8
20
MAX9508 toc02
VOUT = 100mVP-P
NORMALIZED TO 1MHz
10
1.0
MAX9508 toc01
20
LARGE-SIGNAL GAIN
vs. FREQUENCY
MAX9508 toc03
SMALL-SIGNAL GAIN
vs. FREQUENCY
SUPPLY CURRENT (mA)
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
2.5
2.0
1.5
1.0
0.5
11.5
1.96
11.0
1.95
-50
-25
0
25
50
75
TEMPERATURE (°C)
6
100
125
0
-0.5
-50
-25
0
25
50
75
TEMPERATURE (°C)
100
125
-0.5
0
0.5
1.0
INPUT VOLTAGE (V)
_______________________________________________________________________________________
1.5
2.0
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
MAX9508 toc12
MAX9508 toc11
MAX9508 toc10
DIFFERENTIAL
GAIN (%)
12.5T RESPONSE
2T RESPONSE
DIFFERENTIAL GAIN AND PHASE
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
1
2
3
4
5
6
VIN
200mV/div
YIN
200mV/div
VOUT
400mV/div
YOUT
400mV/div
7
DIFFERENTIAL
PHASE (deg)
0.8
0.4
0
-0.4
-0.8
1
2
3
4
5
6
7
400ns/div
100ns/div
STEP
NTC-7 VIDEO TEST
SIGNAL ON CVBS OUTPUTS
PAL MULTIBURST RESPONSE
PAL COLOR BARS
MAX9508 toc14
MAX9508 toc13
CVBSIN
500mV/div
CVBSOUT1
1V/div
MAX9508 toc15
CVBSIN
500mV/div
CVBSIN
500mV/div
CVBSOUT1
1V/div
CVBSOUT1
1V/div
10μs/div
10μs/div
FIELD SQUARE-WAVE RESPONSE
10μs/div
DISABLE TIME
ENABLE TIME
MAX9508 toc16
MAX9508 toc18
MAX9508 toc17
INPUT VOLTAGE = 1V
INPUT VOLTAGE = 1V
2ms/div
CVBSIN
500mV/div
OUTPUT
1V/div
OUTPUT
1V/div
CVBSOUT1
1V/div
SHDN
1V/div
SHDN
1V/div
2μs/div
200ns/div
_______________________________________________________________________________________
7
MAX9508
Typical Operating Characteristics (continued)
(VDD = VSHDN = +3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V. RL = 150Ω to GND. TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VDD = VSHDN = +3.3V, VSMARTSLEEP = VINT/EXT = VGND = 0V. RL = 150Ω to GND. TA = +25°C, unless otherwise noted.)
PULLDOWN RESISTANCE
vs. TEMPERATURE
PULLDOWN RESISTANCE
DISTRIBUTION
FREQUENCY RESPONSE
AT 6.75MHz DISTRIBUTION
6.0
5.5
PROBABILITY
PULLDOWN RESISTANCE (Ω)
6.5
MAX9508 toc21
MAX9508 toc20
MAX9508 toc19
7.0
PROBABILITY
5.0
4.5
4.0
3.5
3.0
2.5
2.0
-50
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
-25
0
25
50
75
100
125
-0.6
-0.5
TEMPERATURE (°C)
PULLDOWN RESISTANCE (Ω)
-0.4
-0.3
-0.2
ATTENUATION (dB)
INPUT-TO-INPUT CROSSTALK
vs. FREQUENCY
FREQUENCY RESPONSE
AT 27MHz DISTRIBUTION
-20
CROSSTALK (dB)
PROBABILITY
MAX9508 toc23
MAX9508 toc22
0
-40
-60
-80
-100
-120
100k
-52 -50 -48 -46 -44 -42 -40 -38 -36 -34 -32
1M
10M
ATTENUATION (dB)
FREQUENCY (Hz)
OUTPUT-TO-OUTPUT CROSSTALK
vs. FREQUENCY
OUTPUT IMPEDANCE
vs. FREQUENCY
OUTPUT IMPEDANCE (Ω)
-20
-40
-60
-80
100M
MAX9508 toc25
100
MAX9508 toc24
0
CROSSTALK (dB)
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
10
1
-100
-120
0.1
100k
1M
10M
FREQUENCY (Hz)
8
100M
100k
1M
10M
FREQUENCY (Hz)
_______________________________________________________________________________________
100M
-0.1
0
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
PIN
NAME
1, 13
VDD
2
YIN
3, 8
GND
4
CVBSIN
5
EXTCVBSIN
6
SHDN
7
N.C.
9
CVBSOUT2
10
CVBSOUT1
11
YOUT
12
COUT
FUNCTION
Power Supply. Bypass VDD with a 0.1µF capacitor to ground.
Luma Video Input. Directly connect this input to the video DAC output.
Ground
Internal CVBS Signal Input. Directly connect this input to the video DAC output.
External CVBS Signal Input. AC-couple the signal through a 0.1µF capacitor to this input.
Active-Low Shutdown Logic Input. Connect to logic low to place device in shutdown. Connect to
logic high for normal operation.
No Connection. Connect to GND.
CVBS Output 2
CVBS Output 1. CVBSOUT1 is actively pulled to GND when INT/EXT is logic high.
Luma Video Output
Chroma Video Output
Internal/External CVBS Logic Input. Connect INT/EXT low to process CVBS video signals from
CVBSIN input. Connect INT/EXT high to process CVBS video signals from EXTCVBSIN input.
14
INT/EXT
15
SMARTSLEEP
16
CIN
Chroma Video Input. Directly connect this input to the video DAC output.
EP
EP
Exposed Pad. Connect EP to GND. EP is also internally connected to GND.
SmartSleep Logic Input. Connect to logic high to activate SmartSleep operation.
_______________________________________________________________________________________
9
MAX9508
Pin Description
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
+3.3V
0.1μF
VDD
75Ω
DVD CHIP
TO TFT LCD
LOAD SENSE
BUFFER
CIN
CURRENT
DAC
COUT
6dB
LPF
75Ω
SVIDEO CHROMA
75Ω
TO TFT LCD
LOAD SENSE
BUFFER
YIN
CURRENT
DAC
YOUT
6dB
LPF
75Ω
SVIDEO LUMA
INT/EXT
SMARTSLEEP
+3.3V
MAX9508
CONTROL
LOGIC
MICROCONTROLLER
SHDN
ACTIVE VIDEO
DETECT
LOAD SENSE
CVBSOUT1
6dB
75Ω
CVBS
CVBSIN
CURRENT
DAC
BUFFER
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
6dB
CVBSOUT2
75Ω
TO Y/C SEPARATION
0.1μF
GND
Figure 1. Typical Application Circuit for Portable DVD Player
Detailed Description
In the typical application circuit for a portable DVD
player (Figure 1), the current DACs on a DVD decoder
chip generate video signals. When the internal signal
sources are selected, the MAX9508 filters those signals
and then drives the video connectors through a 75Ω
back termination resistor. When external video sources
are selected, the MAX9508 selects the external composite video signal (EXTCVBSIN), filters, and amplifies
it. The output stages of the amplifiers connected to
10
COUT, YOUT, and CVBSOUT1 become high impedance. The n-channel switch at CVBSOUT1 turns on,
thereby converting the back termination resistor into an
input termination resistor.
SmartSleep Feature
The SmartSleep feature is activated when the SMARTSLEEP
input is connected to logic high. The SmartSleep feature
provides intelligent power management by selectively
disabling the filters and output amplifiers based on
the presence of video signals or loads attached to the
______________________________________________________________________________________
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
+3.3V
7μA
VDD
VIDEO ENCODER
LOAD SENSE
BUFFER
OFF
CIN
CURRENT
DAC
6dB
LPF
OFF
75Ω
SVIDEO
CHROMA
OFF
OFF
LOAD SENSE
BUFFER
OFF
YIN
CURRENT
DAC
COUT
6dB
LPF
OFF
YOUT
75Ω
SVIDEO
LUMA
OFF
OFF
INT/EXT
+3.3V
MAX9508
CONTROL
LOGIC
SMARTSLEEP
SHDN
LOAD SENSE
ACTIVE VIDEO
DETECT
OFF
6dB
CVBSIN
CURRENT
DAC
NO VIDEO
SIGNAL
EXTCVBSIN
OFF
CLAMP
OFF
75Ω
CVBS 1
OFF
BUFFER
+3.3V
CVBSOUT1
LPF
LOAD SENSE
OFF
OFF
6dB
CVBSOUT2
75Ω
CVBS 2
OFF
GND
Figure 2. Standby Mode
______________________________________________________________________________________
11
MAX9508
Standby Mode
In standby mode, the filters and output amplifiers are
off and only the active video detect circuit is operational. Quiescent current consumption is approximately
7µA (Figure 2). The active video detect circuit checks if
sync is present on the CVBSIN signal. If no sync is
detected the device remains in standby mode.
outputs. If the SmartSleep feature is not activated and
the part is not in shutdown, the filters and output amplifiers completely turn on, regardless of whether there is
a video signal at the CVBSIN input and whether there
are loads connected at the outputs.
SmartSleep only works with DC-coupled loads.
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
Active-Detect Mode
The active video detect circuit slices the CVBSIN signal
at 4.7% of the power supply (155mV for a 3.3V supply).
If the transitions occur at a rate of 14.3kHz or higher, a
video signal is present. When the MAX9508 detects a
video signal with sync at the CVBSIN input, the control
logic enters the active-detect mode and enables the
load sense circuitry (Figure 3). The supply current is
typically 17µA.
If an output load is not connected to any amplifier, the
MAX9508 remains in active detect mode. Eight times per
second, each load-sense circuit checks for a load by
connecting an internal 15kΩ pullup resistor to the output
for 1ms. If the output is pulled up, then no load is present. If the output stays low, a load is connected.
+3.3V
17μA
VDD
VIDEO ENCODER
LOAD SENSE
BUFFER
CIN
CURRENT
DAC
OFF
75Ω
SVIDEO
CHROMA
OFF
OFF
LOAD SENSE
BUFFER
YIN
CURRENT
DAC
COUT
6dB
LPF
OFF
YOUT
6dB
LPF
75Ω
SVIDEO
LUMA
OFF
OFF
INT/EXT
+3.3V
NO
LOADS
MAX9508
CONTROL
LOGIC
SMARTSLEEP
SHDN
LOAD SENSE
ACTIVE VIDEO
DETECT
CVBSOUT1
6dB
CVBSIN
CURRENT
DAC
VIDEO SIGNAL
PRESENT
EXTCVBSIN
OFF
CLAMP
OFF
0
TO
50mV
CVBS 1
OFF
BUFFER
+3.3V
75Ω
LPF
LOAD SENSE
OFF
6dB
CVBSOUT2
75Ω
OFF
GND
Figure 3. Active-Detect Mode with No Output Loads
12
______________________________________________________________________________________
CVBS 2
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
output is sourcing current during a horizontal line time.
If no sourcing current is detected within one horizontal
line time (approximately 64µs), the load has been disconnected and the amplifier returns to active-detect
mode. If, at any time, the input video signal is removed,
the MAX9508 returns to standby mode.
If the SmartSleep feature is not activated and the part is
not in shutdown, the filters and amplifiers completely
turn on, regardless of whether there is a video signal at
the CVBSIN input and whether there are loads connected at the outputs.
+3.3V
2.9mA QUIESCENT
SUPPLY CURRENT
PLUS
OUTPUT LOAD CURRENT
VDD
VIDEO ENCODER
LOAD SENSE
BUFFER
CIN
CURRENT
DAC
OFF
SVIDEO
CHROMA
LOAD SENSE
YIN
YOUT
6dB
LPF
OFF
75Ω
OFF
OFF
BUFFER
CURRENT
DAC
COUT
6dB
LPF
75Ω
SVIDEO
LUMA
OFF
OFF
INT/EXT
+3.3V
MAX9508
CONTROL
LOGIC
SMARTSLEEP
SHDN
LOAD SENSE
ACTIVE VIDEO
DETECT
CVBSOUT1
6dB
75Ω
CVBS1
CVBSIN
CURRENT
DAC
75Ω
BUFFER
+3.3V
VIDEO SIGNAL
PRESENT
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
OFF
0
TO
50mV
6dB
CVBSOUT2
75Ω
CVBS 2
OFF
GND
Figure 4. Full-Operation Mode with CVBSOUT1 Loaded
______________________________________________________________________________________
13
MAX9508
Full-Operation Mode
If a load is connected to an output, the corresponding
filter and amplifier turn on and remain on until the output load is disconnected. In full-operation mode,
SmartSleep intelligently reduces the supply current
based on the input signal presence and output loading.
Figures 4, 5, and 6 show which portions of the
MAX9508 turn on and which remain off with different
load configurations.
When an amplifier is on, it continually checks if the load
has been disconnected by detecting if the amplifier
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
+3.3V
2.9mA QUIESCENT
SUPPLY CURRENT
PLUS
OUTPUT LOAD CURRENT
VDD
VIDEO ENCODER
LOAD SENSE
BUFFER
CIN
CURRENT
DAC
OFF
SVIDEO
CHROMA
LOAD SENSE
BUFFER
YOUT
6dB
LPF
OFF
75Ω
OFF
OFF
YIN
CURRENT
DAC
COUT
6dB
LPF
75Ω
SVIDEO
LUMA
OFF
OFF
INT/EXT
+3.3V
MAX9508
CONTROL
LOGIC
SMARTSLEEP
SHDN
LOAD SENSE
ACTIVE VIDEO
DETECT
CVBSOUT1
6dB
CVBSIN
CURRENT
DAC
VIDEO SIGNAL
PRESENT
CVBS 1
OFF
BUFFER
+3.3V
75Ω
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
OFF
0
TO
50mV
6dB
CVBSOUT2
75Ω
75Ω
GND
Figure 5. Full-Operation Mode with CVBSOUT2 Loaded
14
CVBS2
______________________________________________________________________________________
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
MAX9508
+3.3V
10.5mA QUIESCENT
SUPPLY CURRENT
PLUS
OUTPUT LOAD CURRENT
VDD
VIDEO ENCODER
LOAD SENSE
BUFFER
CIN
CURRENT
DAC
COUT
6dB
LPF
75Ω
SVIDEO CHROMA
75Ω
LOAD SENSE
BUFFER
YIN
CURRENT
DAC
YOUT
6dB
LPF
75Ω
SVIDEO LUMA
75Ω
INT/EXT
+3.3V
MAX9508
CONTROL
LOGIC
SMARTSLEEP
SHDN
LOAD SENSE
ACTIVE VIDEO
DETECT
CVBSOUT1
6dB
75Ω
CVBS1
CVBSIN
CURRENT
DAC
75Ω
BUFFER
+3.3V
VIDEO SIGNAL
PRESENT
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
OFF
0
TO
50mV
6dB
CVBSOUT2
75Ω
CVBS2
75Ω
GND
Figure 6. Full-Operation Mode with All Outputs Loaded
______________________________________________________________________________________
15
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
Internal Mode Versus External Mode
source such as a DVD chip (Figure 7). The 2:1 multiplexer selects the video signal on CVBSIN. The
EXTCVBSIN video signal is ignored.
Internal Mode
Set the INT/EXT control input low for internal mode. The
MAX9508 processes video signals from an internal
+3.3V
0.1μF
13mA QUIESCENT
SUPPLY CURRENT
VDD
75Ω
DVD CHIP
TO TFT LCD
LOAD SENSE
BUFFER
CIN
CURRENT
DAC
COUT
6dB
LPF
75Ω
SVIDEO CHROMA
75Ω
TO TFT LCD
LOAD SENSE
BUFFER
YIN
CURRENT
DAC
YOUT
6dB
LPF
75Ω
SVIDEO LUMA
LOGIC
LOW
INT/EXT
SMARTSLEEP
MICROCONTROLLER
+3.3V
MAX9508
CONTROL
LOGIC
SHDN
ACTIVE VIDEO
DETECT
LOAD SENSE
CVBSOUT1
6dB
75Ω
CVBS
CVBSIN
CURRENT
DAC
BUFFER
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
OFF
6dB
CVBSOUT2
75Ω
0.1μF
GND
Figure 7. Internal Mode Operation for Portable DVD Applications
16
______________________________________________________________________________________
TO Y/C SEPARATION
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
nals are ignored. The block drawing of the MAX9508 in
Figure 8 shows which circuits are off while in external
mode. SmartSleep does not function in external mode,
and the SMARTSLEEP input is ignored.
+3.3V
4.3mA QUIESCENT
SUPPLY CURRENT
VDD
75Ω
DVD CHIP
TO TFT LCD
LOAD SENSE
BUFFER
OFF
CIN
CURRENT
DAC
6dB
LPF
OFF
COUT
OFF
OFF
75Ω
SVIDEO CHROMA
75Ω
TO TFT LCD
LOAD SENSE
BUFFER
OFF
YIN
CURRENT
DAC
6dB
LPF
OFF
LOGIC
HIGH
YOUT
75Ω
SVIDEO LUMA
OFF
OFF
INT/EXT
MICROCONTROLLER
0V OR SMARTSLEEP
+3.3V
SHDN
+3.3V
MAX9508
CONTROL
LOGIC
ACTIVE VIDEO
DETECT
LOAD SENSE
OFF
6dB
CVBSIN
CURRENT
DAC
CVBSOUT1
75Ω
CVBS
75Ω
VIDEO
SOURCE
OFF
BUFFER
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
6dB
CVBSOUT2
75Ω
TO Y/C SEPARATION
0.1μF
GND
Figure 8. External Mode Operation for Portable DVD Applications
______________________________________________________________________________________
17
MAX9508
External Mode
Set the INT/EXT control input high for external mode.
The 2:1 multiplexer selects the video signal on
EXTCVBSIN (Figure 8). The YIN, CIN, and CVBSIN sig-
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
Inputs
applied to YIN, CIN, and CVBSIN. The RGB set and the
YPbPr set can also be inputs to YIN, CIN, and CVBSIN
(Figure 9).
The EXTCVBSIN input can only handle signals with a
sync pulse, such as composite, video, or luma.
Because the DC level of an external video input signal
is unknown, the external video signal is AC-coupled
through a 0.1µF capacitor, and a sync tip clamp sets
the internal DC level of the MAX9508. A 2:1 multiplexer
under the control of the INT/EXT input selects either the
signal at CVBSIN or EXTCVBSIN.
The MAX9508 video inputs YIN, CIN, and CVBSIN
should be directly connected to the output of the video
current DAC. DC-coupling ensures that the input signals are ground referenced such that the sync tip of
composite or luma signals is within 50mV of ground
and the blank level of the chroma signal is between
0.5V and 0.65V. Since the input buffer is identical for
YIN, CIN, and CVBSIN, any standard-definition video
signal can be applied to those inputs as long as the
signal is between ground and 1.05V when VDD = 2.7V.
For example, three composite video signals could be
+3.3V
0.1μF
VDD
VIDEO ENCODER
Pr/R
CURRENT
DAC
LOAD SENSE
BUFFER
CIN
75Ω
Pr/R
LOAD SENSE
BUFFER
Pb/B
YIN
CURRENT
DAC
COUT
6dB
LPF
YOUT
6dB
LPF
75Ω
Pb/B
INT/EXT
+3.3V
MAX9508
CONTROL
LOGIC
SMARTSLEEP
SHDN
ACTIVE VIDEO
DETECT
LOAD SENSE
CVBSOUT1
6dB
Y/G
75Ω
Y/G
CVBSIN
CURRENT
DAC
BUFFER
+3.3V
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
6dB
CVBSOUT2
75Ω
GND
Figure 9. Y, Pr, Pb or RGB Set Applied to MAX9508
18
______________________________________________________________________________________
Y/G
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
Outputs
The video output amplifiers can both source and sink
load current, allowing output loads to be DC- or ACcoupled. The amplifier output stage needs about
300mV of headroom from either supply rail. The
MAX9508 has an internal level-shift circuit that positions
the sync tip at approximately 300mV at the output. The
blank level of the chroma output is positioned at
approximately 1.3V if the blank level of the chroma
input signal is 0.5V. The blank level of the chroma output is positioned at approximately 1.5V if the blank level
of the chroma input signal is 0.6V.
If the supply voltage is greater than 3.135V (5% below
a 3.3V supply), each amplifier can drive two DC-coupled video loads to ground. If the supply is less than
3.135V, each amplifier can drive only one DC-coupled
or AC-coupled video load.
Shutdown
When SHDN is low, the MAX9508 draws typically less
than 10nA supply current. All the amplifier outputs
become high impedance. The effective output resistance at the video outputs is 28kΩ, due to the internal
feedback resistors to ground.
Applications Information
Reducing Power Consumption
in the Video DACs
YIN, CIN, and CVBSIN have high-impedance input
buffers and can work with source resistances as high as
300Ω. To reduce power dissipation in the video DACs,
the DAC output resistor can be scaled up in value. The
reference resistor that sets the reference current inside
the video DACs must also be similarly scaled up. For
instance, if the output resistor is 37.5Ω, the DAC must
source 26.7mA when the output is 1V. If the output resistor is increased to 300Ω, the DAC only needs to source
3.33mA when the output is 1V.
There is parasitic capacitance from the DAC output to
ground. That capacitance in parallel with the DAC output resistor forms a pole that can potentially roll off the
frequency response of the video signal. For example,
300Ω in parallel with 50pF creates a pole at 10.6MHz.
To minimize this capacitance, reduce the area of the
signal trace attached to the DAC output as much as
possible, and place the MAX9508 as close to the video
DAC outputs as possible.
AC-Coupling the Outputs
The outputs can be AC-coupled since the output stage
can source and sink current as shown in Figure 10.
Coupling capacitors should be 220µF or greater to
keep the highpass filter formed by the 150Ω equivalent
resistance of the video transmission line to a corner frequency of 4.8Hz or below. The frame rate of PAL systems is 25Hz, and the frame rate of NTSC systems is
30Hz. The corner frequency should be well below the
frame rate. SmartSleep only works with DC-coupled
loads.
______________________________________________________________________________________
19
MAX9508
Video Reconstruction Filter
The MAX9508 filter passband is 6.75MHz, which makes
the device suitable for the higher bandwidth video signals from a DVD chip. Broadcast video signals actually
require less bandwidth because of channel limitations:
NTSC signals have a 4.2MHz bandwidth, and PAL signals have a 5MHz bandwidth. Video signals from a DVD
player are not channel limited; therefore, the bandwidth
of DVD video signals can push right against the Nyquist
limit of 6.75MHz. (Recommendation ITU-R BT.601-5
specifies 13.5MHz as the sampling rate for standarddefinition video). Therefore, the maximum bandwidth of
the signal is 6.75MHz. To ease the filtering requirements, most modern video systems oversample by two
times, clocking the video current DAC at 27MHz.
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
+3.3V
0.1μF
VDD
SET-TOP BOX CHIP
LOAD SENSE
BUFFER
CURRENT
DAC
CIN
CURRENT
DAC
YIN
COUT
6dB
LPF
75Ω
220μF
75Ω
220μF
75Ω
220μF
SVIDEO
CHROMA
LOAD SENSE
BUFFER
YOUT
6dB
LPF
SVIDEO
LUMA
INT/EXT
+3.3V
MAX9508
CONTROL
LOGIC
SMARTSLEEP
SHDN
LOAD SENSE
ACTIVE VIDEO
DETECT
CVBSOUT1
6dB
CVBS 1
CVBSIN
CURRENT
DAC
BUFFER
LPF
EXTCVBSIN
GND
LOAD SENSE
CLAMP
OFF
6dB
CVBSOUT2
75Ω
GND
Figure 10. AC-Coupled Outputs
Power-Supply Bypassing and Ground
The MAX9508 operates from a single-supply voltage
down to 2.7V, allowing for low-power operation. Bypass
VDD to GND with a 0.1µF capacitor. Place all external
components as close to the device as possible.
20
______________________________________________________________________________________
220μF
CVBS 2
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
LOAD SENSE
BUFFER
CIN
COUT
6dB
LPF
LOAD SENSE
BUFFER
YIN
YOUT
6dB
LPF
INT/EXT
SMARTSLEEP
MAX9508
CONTROL
LOGIC
SHDN
ACTIVE VIDEO
DETECT
0
TO
50mV
LOAD SENSE
300mV
TO
400mV
CVBSOUT1
6dB
CVBSIN
BUFFER
LPF
EXTCVBSIN
LOAD SENSE
CLAMP
6dB
CVBSOUT2
______________________________________________________________________________________
21
MAX9508
Block Diagrams (continued)
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
MAX9508
Pin Configuration
Chip Information
YOUT
CVBSOUT1
CVBSOUT2
TOP VIEW
COUT
PROCESS: BiCMOS
12
11
10
9
VDD 13
8
GND
INT/EXT 14
7
N.C.
6
SHDN
5
EXTCVBSIN
MAX9508
SMARTSLEEP 15
2
3
4
CVBSIN
VDD
1
GND
+
YIN
CIN 16
THIN QFN
(3mm x 3mm)
22
______________________________________________________________________________________
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
PACKAGE CODE
DOCUMENT NO.
16 TQFN-EP
T1633-4
21-0136
(NE - 1) X e
E
MARKING
12x16L QFN THIN.EPS
PACKAGE TYPE
E/2
D2/2
(ND - 1) X e
D/2
AAAA
e
CL
D
D2
k
CL
b
0.10 M C A B
E2/2
L
E2
0.10 C
C
L
C
L
0.08 C
A
A2
A1
L
L
e
e
PACKAGE OUTLINE
8, 12, 16L THIN QFN, 3x3x0.8mm
21-0136
I
1
2
______________________________________________________________________________________
23
MAX9508
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
MAX9508
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
Package Information (continued)
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.)
PKG
8L 3x3
12L 3x3
16L 3x3
REF.
MIN. NOM. MAX.
MIN. NOM. MAX.
MIN. NOM. MAX.
A
0.70
0.75
0.80
0.70
0.75
0.80
0.70
0.75
0.80
b
0.25
0.30
0.35
0.20
0.25
0.30
0.20
0.25
0.30
D
2.90
3.00
3.10
2.90
3.00
3.10
2.90
3.00
3.10
E
2.90
3.00
3.10
2.90
3.00
3.10
2.90
3.00
3.10
0.75
0.45
0.65
0.30
e
L
0.65 BSC.
0.35
0.55
0.50 BSC.
0.50 BSC.
0.55
0.40
N
8
12
16
ND
2
3
4
NE
2
3
4
0
A1
A2
k
0.02
0.05
0
0.20 REF
0.25
-
0.02
0.05
0
0.20 REF
-
0.25
-
EXPOSED PAD VARIATIONS
0.02
0.50
0.05
0.20 REF
-
0.25
-
PKG.
CODES
D2
MIN.
E2
NOM.
MAX.
MIN.
NOM.
MAX.
PIN ID
JEDEC
TQ833-1
0.25
0.70
1.25
0.25
0.70
1.25
0.35 x 45°
T1233-1
0.95
1.10
1.25
0.95
1.10
1.25
0.35 x 45°
WEEC
WEED-1
T1233-3
0.95
1.10
1.25
0.95
1.10
1.25
0.35 x 45°
WEED-1
T1233-4
0.95
1.10
1.25
0.95
1.10
1.25
0.35 x 45°
WEED-1
T1633-2
0.95
1.10
1.25
0.95
1.10
1.25
0.35 x 45°
WEED-2
T1633F-3
0.65
0.80
0.95
0.65
0.80
0.95
0.225 x 45°
WEED-2
T1633FH-3
0.65
0.80
0.95
0.65
0.80
0.95
0.225 x 45°
WEED-2
T1633-4
0.95
1.10
1.25
0.95
1.10
1.25
0.35 x 45°
WEED-2
T1633-5
0.95
1.10
1.25
0.95
1.10
1.25
0.35 x 45°
WEED-2
-
NOTES:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994.
ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES.
N IS THE TOTAL NUMBER OF TERMINALS.
THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL CONFORM TO
JESD 95-1 SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED
WITHIN THE ZONE INDICATED. THE TERMINAL #1 IDENTIFIER MAY BE EITHER A MOLD OR
MARKED FEATURE.
DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN 0.20 mm AND 0.25 mm
FROM TERMINAL TIP.
ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY.
DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION.
COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS
.
DRAWING CONFORMS TO JEDEC MO220 REVISION C.
MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY.
NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY.
WARPAGE NOT TO EXCEED 0.10mm.
PACKAGE OUTLINE
8, 12, 16L THIN QFN, 3x3x0.8mm
21-0136
24
______________________________________________________________________________________
I
2
2
CVBS/S-Video Filter Amplifier with
SmartSleep and Bidirectional Video Support
REVISION
NUMBER
REVISION
DATE
2
1/09
DESCRIPTION
Removed QSOP package
PAGES
CHANGED
1, 2, 9, 22
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 25
© 2009 Maxim Integrated Products
Heaney
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX9508
Revision History
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