Maxim MAX9658 Quad video (filter) amplifiers with input sync-tip clamp Datasheet

19-4453; Rev 0; 2/09
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
The MAX9657 is a small, low-power, quad video amplifier with input sync-tip clamps. It features a bandwidth
of 15MHz, making it suitable for not only standard-definition video signals, but also video graphics array
(VGA) signals with a 640 x 480 resolution at up to 85Hz
refresh rate.
The MAX9658 is a quad video amplifier with integrated
lowpass filters and input sync-tip clamps. The lowpass
filters typically have ±1dB passband flatness out to
9.5MHz and 47dB attenuation at 27MHz. Specially suited for composite video signals, the MAX9658 is ideal
for performing anti-alias filtering at the inputs of a digital
video recorder or for performing reconstruction filtering
at the outputs of a SCART set-top box.
Both devices require that the incoming video signals be
AC-coupled to the inputs. The input sync-tip clamps set
the internal DC level of the video signals.
The amplifiers have 2V/V gain, and the outputs can be
DC-coupled to a 75Ω load, which is the equivalent of
two video loads, or AC-coupled to a 150Ω load.
Both the MAX9657/MAX9658 feature a low-power shutdown mode, in which supply current is reduced to
35µA.
The MAX9657/MAX9658 operate from a single 2.7V to
3.6V supply, are specified over the -40°C to +125°C
automotive temperature range, and are offered in a
small, 16-pin QSOP package.
Applications
Features
♦ Quad Channel
♦ 9.5MHz, ±1dB Passband (MAX9658)
♦ 47dB Attenuation at 27MHz (MAX9658)
♦ Fixed Gain of 2V/V
♦ Low Power: 21mA
♦ 2.7V to 3.6V Single-Supply Operation
Ordering Information
PART
PIN-PACKAGE
STANDARD-DEFINITION
VIDEO FILTER
MAX9657AEE+
16 QSOP
No
MAX9658AEE+
16 QSOP
Yes
Note: All devices are specified over the -40°C to +125°C operating temperature range.
+Denotes a lead(Pb)-free/RoHS-compliant package.
Functional Diagram
MAX9657/MAX9658
UNKNOWN
BIAS
SHDN
300mV
IN0
OUT0
LPF*
Set-Top Boxes
AV = 2V/V
Digital Video Recorders
CLAMPREF
IN1
OUT1
LPF*
AV = 2V/V
CLAMPREF
IN2
OUT2
LPF*
AV = 2V/V
Typical Application Circuits and Pin Configuration appear
at end of data sheet.
CLAMPREF
IN3
OUT3
LPF*
AV = 2V/V
CLAMPREF
GND
*LOWPASS FILTER IN MAX9658 ONLY.
________________________________________________________________ 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
MAX9657/MAX9658
General Description
MAX9657/MAX9658
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
VDD to GND ..........................................................-0.3V to +4V
Input Pins, SHDN .....................................(GND - 0.3V) to +4V
Duration of Output Short Circuit to VDD or GND ........Continuous
Continuous Input Current
Input Pins......................................................................±20mA
Continuous Power Dissipation (TA = +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C)...........667mW
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 = 3.3V, VGND = 0V, V SHDN = VDD, 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
2.7
UNITS
Supply Voltage Range
VDD
Guaranteed by power-supply rejection test
3.3
3.6
V
Quiescent Supply Current
IDD
No load
21
45
mA
Shutdown Supply Current
ISHDN
SHDN = GND
35
70
µA
Sync-Tip Clamp Level
VCLP
0.3
0.39
V
0.23
Guaranteed by outputvoltage swing
Input Voltage Range
2.7V ≤ VDD ≤
3.6V
1.05
3.0V ≤ VDD ≤
3.6V
1.2
VP-P
Sync-tip clamp; percentage reduction in
sync pulse (0.3VP-P); guaranteed by input
clamping current measurement
Sync Crush
Input Clamping Current
1
Maximum Input Source
Resistance
300
DC Voltage Gain (Note 2)
AV
RL = 150Ω to GND
(Note 2)
VDD = 2.7V,
0V ≤ VIN ≤ 1.05V
1.96
VDD = 3V,
0V ≤ VIN ≤ 1.2V
1.96
DC Gain Mismatch
Guaranteed by DC voltage gain
Output Level
Measured at VOUT, CIN_ = 0.1µF to GND
Output-Voltage Swing
2
2
2
%
2
µA
Ω
2.04
V/V
2
2.04
+2
%
0.3
0.39
V
-2
0.218
Measured at output, VDD = 2.7V, VIN =
VCLP to (VCLP +1.05V), RL = 150Ω to -0.2V
2.1
Measured at output, VDD = 2.7V, VIN =
VCLP to (VCLP +1.05V), RL = 150Ω to VDD/2
2.1
Measured at output, VDD = 3.0V, VIN =
VCLP to (VCLP +1.2V), RL = 150Ω to -0.2V
2.4
Measured at output, VDD = 3.0V, VIN =
VCLP to (VCLP +1.2V), RL = 150Ω to VDD/2
2.4
Measured at output, VDD = 3.135V, VIN =
VCLP to (VCLP +1.05V), RL = 75Ω to -0.2V
2.1
_______________________________________________________________________________________
VP-P
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
(VDD = 3.3V, VGND = 0V, V SHDN = VDD, RL = 150Ω to GND, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Output Short-Circuit Current
Output Resistance
ROUT
CONDITIONS
TYP
140
Short to VDD (sinking)
70
VOUT = 1.5V, -10mA ≤ ILOAD ≤ +10mA
2.7V ≤ VDD ≤ 3.6V
Power-Supply Rejection Ratio
MIN
Short to GND (sourcing)
0.2
48
f = 100kHz, 100mVP-P
64
20
MAX
UNITS
mA
Ω
dB
Small-Signal Bandwidth
VOUT = 100mVP-P (MAX9657 only)
27
MHz
Large-Signal Bandwidth
VOUT = 2VP-P (MAX9657 only)
15
MHz
Slew Rate
MAX9657 only
65
V/µs
Settling Time
Settled to within 0.1% of final value
(MAX9657 only)
75
ns
VOUT = 2VP-P, reference frequency is
100kHz ±1dB passband flatness (MAX9658
only)
9.5
MHz
Standard-Definition
Reconstruction Filter
VOUT = 2VP-P, reference
frequency is 100kHz
(MAX9658 only)
f = 5.5MHz
0.1
f = 9.5MHz
-1
f = 10MHz
-3
f = 27MHz
-47
dB
Differential Gain
DG
5-step modulated staircase of 129mV step
size and 286mV peak-to-peak subcarrier
amplitude, f = 4.43MHz
0.4
%
Differential Phase
DP
5-step modulated staircase of 129mV step
size and 286mV peak-to-peak subcarrier
amplitude, f = 4.43MHz
0.45
deg
Group-Delay Distortion
100kHz ≤ f ≤ 5MHz, outputs are 2VP-P
9
ns
Peak Signal to RMS Noise
100kHz ≤ f ≤ 5MHz
71
dB
2T Pulse Response
2T = 200ns
0.2
K%
2T Bar Response
2T = 200ns; bar time is 18µs; the beginning
2.5%, and the ending 2.5% of the bar time
is ignored
0.2
K%
2T Pulse-to-Bar K Rating
2T = 200ns; bar time is 18µs; the beginning
2.5%, and the ending 2.5% of the bar time
is ignored
0.3
K%
Nonlinearity
5-step staircase
0.1
%
Output Impedance
f = 5.5MHz
8.07
Ω
All-Hostile Crosstalk
Output-to-Input Crosstalk
f = 15kHz
-82
f = 4.43MHz
-78
f = 30MHz
-68
dB
dB
_______________________________________________________________________________________
3
MAX9657/MAX9658
ELECTRICAL CHARACTERISTICS (continued)
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 3.3V, VGND = 0V, V SHDN = VDD, 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
0.3 x
VDD
V
LOGIC SIGNALS (SHDN)
Logic-Low Threshold
VIL
Logic-High Threshold
VIH
Logic Input Current
IIN
0.7 x
VDD
V
10
µA
Note 1: All devices are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design.
Note 2: Voltage gain (AV) is a two-point measurement in which the output-voltage swing is divided by the input-voltage swing.
Typical Operating Characteristics (MAX9657)
(VDD = 3.3V, VGND = 0, V SHDN = VDD, RL = 150Ω to GND, TA = +25°C.)
VIN = 50mVP-P
NOTE: GAIN IS NORMALIZED TO 0dB
2
1
0
-1
GAIN (dB)
-2
-3
-4
-5
-6
10M
1M
10M
1M
10M
FREQUENCY (Hz)
LARGE-SIGNAL GAIN FLATNESS
vs. FREQUENCY
VIDEO CROSSTALK
vs. FREQUENCY
VIDEO GROUP DELAY DISTORTION
vs. FREQUENCY
0
-20
0
-40
GAIN (dB)
-1
-2
-3
-60
ALL-HOSTILE
-80
-4
-5
-100
2 ADJACENT CHANNELS
10M
FREQUENCY (Hz)
100M
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
45
40
35
30
25
20
10
5
0
-120
1M
100M
15
1 ADJACENT CHANNEL
-6
-7
50
GROUP DELAY (ns)
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
MAX9657 toc05
1
100k
100k
100M
FREQUENCY (Hz)
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
2
100k
100M
FREQUENCY (Hz)
MAX9657 toc04
3
1M
-15
-20
-25
-30
-35
-40
-45
-50
-7
100k
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
MAX9657 toc06
-10
-15
-20
-25
-30
-35
-40
-45
-50
4
10
5
0
-5
-10
MAX9657 toc03
3
MAX9657 toc01
VIN = 50mVP-P
NOTE: GAIN IS NORMALIZED TO 0dB
GAIN (dB)
GAIN (dB)
10
5
0
-5
LARGE-SIGNAL GAIN
vs. FREQUENCY
SMALL-SIGNAL GAIN FLATNESS
vs. FREQUENCY
MAX9657 toc02
SMALL-SIGNAL GAIN
vs. FREQUENCY
GAIN (dB)
MAX9657/MAX9658
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
100k
1M
10M
FREQUENCY (Hz)
100M
100k
1M
10M
FREQUENCY (Hz)
_______________________________________________________________________________________
100M
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
VOLTAGE GAIN
vs. TEMPERATURE
-30
-40
-50
2.02
2.01
1.99
1.98
-70
1.97
1.96
100k
1M
10M
100M
3
-25
0
25
50
75
100
125
1
2
3
4
MAX9657 toc09
5
f = 3.58MHz
0
1
2
3
4
5
4
12.5T RESPONSE
MAX9657 toc11
MAX9657 toc12
IN
200mV/div
IN
200mV/div
OUT
400mV/div
OUT
400mV/div
5
f = 4.43MHz
2
3
4
NTC-7 VIDEO TEST SIGNAL
FIELD SQUARE WAVE
MAX9657 toc13
IN
500mV/div
PULSE RESPONSE
MAX9657 toc14
IN
500mV/div
OUT
1V/div
10μs/div
400ns/div
100ns/div
5
OUT
1V/div
2ms/div
MAX9657 toc15
1
INPUT (700mV/div)
0
OUTPUT (700mV/div)
0.8
0.6
0.4
0.2
0
-0.2
-0.4
2
-50
2T RESPONSE
f = 4.43MHz
1
0
MAX9657 toc10
DIFFERENTIAL GAIN (%)
DIFFERENTIAL PHASE (deg)
DIFFERENTIAL GAIN AND PHASE
0
0.8
0.6
0.4
0.2
0
-0.2
-0.4
f = 3.58MHz
TEMPERATURE (°C)
FREQUENCY (Hz)
0.10
0.05
0
-0.05
-0.10
-0.15
-0.25
0.10
0.05
0
-0.05
-0.10
-0.15
-0.20
2.00
-60
-80
DIFFERENTIAL GAIN (%)
2.03
VOLTAGE GAIN (V/V)
PSRR (dB)
-20
MAX9657 toc08
VDD = 3.3V + 100mVP-P
-10
DIFFERENTIAL GAIN AND PHASE
2.04
MAX9657 toc07
0
DIFFERENTIAL PHASE (deg)
VIDEO PSRR
vs. FREQUENCY
TIME (100ns/div)
_______________________________________________________________________________________
5
MAX9657/MAX9658
Typical Operating Characteristics (MAX9657) (continued)
(VDD = 3.3V, VGND = 0, V SHDN = VDD, RL = 150Ω to GND, TA = +25°C.)
Typical Operating Characteristics (MAX9657) (continued)
(VDD = 3.3V, VGND = 0, V SHDN = VDD, RL = 150Ω to GND, TA = +25°C.)
0.34
0.33
0.32
0.31
0.30
1.04
1.02
1.00
0.98
0.96
0.94
0.92
0.29
0.28
0.90
-50
-25
0
25
50
75
100
125
500
MAX9657 toc18
0.35
1.06
SYNC-TIP CLAMP CURRENT
vs. INPUT VOLTAGE
MAX9657 toc17
0.36
SYNC-TIP CLAMP CURRENT (μA)
MAX9657 toc16
0.37
VIDEO SYNC-TIP CLAMP CURRENT
vs. TEMPERATURE
SYNC-TIP CLAMP CURRENT (μA)
VIDEO SYNC-TIP CLAMP VOLTAGE
vs. TEMPERATURE
SYNC-TIP CLAMP VOLTAGE (V)
400
300
200
100
0
-100
-50
-25
TEMPERATURE (°C)
0
25
50
75
100
125
TEMPERATURE (°C)
0
0.2
0.4
0.6
MAX9657 toc19
22.0
21.5
21.0
20.5
20.0
19.5
19.0
18.5
18.0
-50
-25
0
25
50
75
100
125
TEMPERATURE (°C)
6
0.8
1.0
INPUT VOLTAGE (V)
QUIESCENT SUPPLY CURRENT
vs. TEMPERATURE
QUIESCENT SUPPLY CURRENT (mA)
MAX9657/MAX9658
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
_______________________________________________________________________________________
1.2
1.4
1.6
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
1
GAIN (dB)
-1
-2
-3
-4
-5
-6
1M
10M
VIDEO CROSSTALK
vs. FREQUENCY
VIDEO GROUP DELAY DISTORTION
vs. FREQUENCY
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
-40
GAIN (dB)
-2
-3
-60
ALL-HOSTILE
-80
-4
-5
-100
1 ADJACENT CHANNEL
-6
-120
100M
100k
1M
FREQUENCY (Hz)
VIDEO PSRR
vs. FREQUENCY
VOLTAGE GAIN
vs. TEMPERATURE
-30
-40
-50
MAX9657 toc27
2.03
VOLTAGE GAIN (V/V)
-20
2.02
2.01
1.99
1.98
-70
1.97
1.96
1M
10M
FREQUENCY (Hz)
100M
100M
0.1
0
-0.1
-0.2
-0.3
-0.4
-0.5
0.8
0.6
0.4
0.2
0
-0.2
-0.4
f = 3.58MHz
0
1
2
3
4
5
2.00
-60
-80
10M
DIFFERENTIAL GAIN AND PHASE
2.04
MAX9657 toc26
VDD = 3.3V + 100mVP-P
1M
FREQUENCY (Hz)
FREQUENCY (Hz)
-10
100k
100M
10M
40
30
DIFFERENTIAL GAIN (%)
10M
50
DIFFERENTIAL PHASE (deg)
1M
80
70
60
20
10
0
2 ADJACENT CHANNELS
-7
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
110
100
90
GROUP DELAY (ns)
-20
120
MAX9657 toc24
0
0
100k
100M
10M
LARGE-SIGNAL GAIN FLATNESS
vs. FREQUENCY
-1
100k
1M
FREQUENCY (Hz)
1
PSRR (dB)
100k
100M
FREQUENCY (Hz)
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
2
100k
MAX9657 toc25
100M
MAX9657 toc28
10M
-10
-15
-20
-25
-30
-35
-40
FREQUENCY (Hz)
MAX9657 toc23
3
1M
VIN = 1VP-P
NOTE: GAIN IS NORMALIZED TO 0dB
-45
-50
-7
100k
0
10
5
0
-5
0
-45
-50
GAIN (dB)
VIN = 50mVP-P
NOTE: GAIN IS NORMALIZED TO 0dB
2
MAX9657 toc22
3
MAX9657 toc21
VIN = 50mVP-P
NOTE: GAIN IS NORMALIZED TO 0dB
MAX9657 toc20
10
5
0
-5
-10
-15
-20
-25
-30
-35
-40
LARGE-SIGNAL GAIN
vs. FREQUENCY
SMALL-SIGNAL GAIN FLATNESS
vs. FREQUENCY
GAIN (dB)
GAIN (dB)
SMALL-SIGNAL GAIN
vs. FREQUENCY
-50
-25
0
25
50
75
100
125
f = 3.58MHz
0
1
2
3
4
5
TEMPERATURE (°C)
_______________________________________________________________________________________
7
MAX9657/MAX9658
Typical Operating Characteristics (MAX9658) (continued)
(VDD = 3.3V, VGND = 0, V SHDN = VDD, RL = 150Ω to GND, TA = +25°C.)
Typical Operating Characteristics (MAX9658) (continued)
(VDD = 3.3V, VGND = 0, V SHDN = VDD, RL = 150Ω to GND, TA = +25°C.)
0.8
0.6
0.4
0.2
0
-0.2
-0.4
2T RESPONSE
f = 4.43MHz
MAX9657 toc30
MAX9657 toc29
DIFFERENTIAL GAIN (%)
DIFFERENTIAL GAIN AND PHASE
0.1
0
-0.1
-0.2
-0.3
-0.4
-0.5
DIFFERENTIAL PHASE (deg)
IN
200mV/div
0
1
2
3
4
5
f = 4.43MHz
OUT
400mV/div
0
1
2
3
4
12.5T RESPONSE
100ns/div
5
NTC-7 VIDEO TEST SIGNAL
MAX9657 toc31
MAX9657 toc32
IN
200mV/div
IN
500mV/div
OUT
1V/div
OUT
400mV/div
400ns/div
10μs/div
FIELD SQUARE WAVE
VIDEO SYNC-TIP CLAMP VOLTAGE
vs. TEMPERATURE
MAX9657 toc33
MAX9657 toc34
0.37
0.36
IN
500mV/div
OUT
1V/div
SYNC-TIP CLAMP VOLTAGE (V)
MAX9657/MAX9658
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
0.35
0.34
0.33
0.32
0.31
0.30
0.29
0.28
2ms/div
-50
-25
0
25
50
75
100
TEMPERATURE (°C)
8
_______________________________________________________________________________________
125
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
1.00
0.98
0.96
0.94
0.92
300
200
100
0
-50
-25
0
25
50
75
100
125
21.5
21.0
20.5
20.0
19.5
19.0
18.5
18.0
-100
0.90
MAX9657 toc37
400
22.0
QUIESCENT SUPPLY CURRENT (mA)
1.02
MAX9657 toc36
1.04
500
SYNC-TIP CLAMP CURRENT (μA)
MAX9657 toc35
SYNC-TIP CLAMP CURRENT (μA)
1.06
QUIESCENT SUPPLY CURRENT
vs. TEMPERATURE
SYNC-TIP CLAMP CURRENT
vs. INPUT VOLTAGE
VIDEO SYNC-TIP CLAMP CURRENT
vs. TEMPERATURE
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
-50
-25
0
25
50
75
100
125
TEMPERATURE (°C)
INPUT VOLTAGE (V)
TEMPERATURE (°C)
Pin Description
PIN
NAME
1
IN0
Video Input Channel 0
FUNCTION
2
IN1
Video Input Channel 1
3
IN2
Video Input Channel 2
4
IN3
Video Input Channel 3
5–8, 15
N.C.
No Connection. Not internally connected.
9
GND
Ground
10
SHDN
Active-Low Shutdown Logic Input. Connect to GND to place device in shutdown. Connect to VDD for
normal operation.
11
OUT3
Video Output Channel 3
12
OUT2
Video Output Channel 2
13
OUT1
Video Output Channel 1
14
OUT0
16
VDD
Video Output Channel 0
Positive Power Supply. Bypass to GND with a 0.1µF capacitor.
_______________________________________________________________________________________
9
MAX9657/MAX9658
Typical Operating Characteristics (MAX9658) (continued)
(VDD = 3.3V, VGND = 0, V SHDN = VDD, RL = 150Ω to GND, TA = +25°C.)
MAX9657/MAX9658
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
Detailed Description
The MAX9657 consists of input sync-tip clamps and
gain of 2V/V output amplifiers capable of driving standard 150Ω loads to ground. It can be used to buffer
video signals, for example, before a crosspoint matrix.
The MAX9658 filters and amplifies video signals. It is
very similar to the MAX9657 except that it also has integrated lowpass filters. This device can be used to provide the anti-alias filtering before the video decoders of
a digital video recorder, or it can be used to do the
reconstruction filtering after a video DAC that references output signals to the positive supply.
Input
The MAX9657/MAX9658 feature sync-tip clamps at the
input that accept video signals with sync pulses.
Composite video with blanking and sync (CVBS) is an
example of a video signal with sync pulses. The synctip voltage is internally set to 300mV.
In shutdown mode, the inputs to the MAX9657/
MAX9658 do not distort the video signal in case the
video source is driving video signals to another video
circuit such as a video multiplexer. The inputs in shutdown mode are biased at VDD/3, which is sufficiently
above ground such that the ESD diodes never forward
bias as the video signal changes. The input resistance
is 220kΩ, which presents negligible loading on the
video current DAC.
Video Filter (MAX9658 Only)
The MAX9658 filters feature ±1dB passband out to
9.5MHz and 47dB attenuation at 27MHz, making the filter suitable for standard-definition video signals from all
sources (e.g., broadcast and DVD). Broadcast video
signals are channel limited: NTSC signals have 4.2MHz
bandwidth and PAL signals have 5MHz bandwidth.
Video signals from a DVD player, however, are not
channel limited, so the bandwidth of DVD video signals
can approach the Nyquist limit of 6.75MHz.
Recommendation: ITU-R BT.601-5 specifies 13.5MHz
as the sampling rate for standard-definition 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.
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
The devices draw approximately 35µA of supply current when SHDN is low. In shutdown mode, the amplifier outputs become high impedance.
Applications Information
AC-Coupling the Outputs
The outputs can be AC-coupled since the output stage
can source and sink current as shown in Figure 1.
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, the frame rate of NTSC systems is
30Hz, and the frame rate of VGA is usually 60Hz or
higher. The corner frequency should be well below the
frame rate.
Power Consumption
The quiescent power consumption and average power
consumption of the MAX9657/MAX9658 are very low
because of the 3.3V operation and low-power circuit
design. Quiescent power consumption is defined when
the MAX9657/MAX9658 are operating without loads
and without any video signals.
Average power consumption represents the normal
power consumption when the devices drive real video
signals into real video loads. It is measured when the
MAX9657/MAX9658 drive a 150Ω load to ground with a
50% flat field, which serves as a proxy for a real video
signal.
Table 1 shows the quiescent and average power consumption of the MAX9657/MAX9658.
Power-Supply Bypassing and Ground
The MAX9657/MAX9658 operate 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 as possible to the
device.
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 approximately 300mV of headroom from either supply rail. The
devices have an internal level-shift circuit that positions
the sync tip at approximately 300mV at the output.
10
______________________________________________________________________________________
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
MAX9657/
MAX9658
GRAPHICS PROCESSING
UNIT OR
MPEG DECODER
DAC
0.1μF
LUMA
IN0
GND
OUT0
LPF*
75Ω
MAX9657/MAX9658
VDD
+3.3V
0.1μF
75Ω
220μF
Y
AV = 2V/V
CLAMPREF
DAC
0.1μF
CHROMA
IN1
OUT1
LPF*
75Ω
75Ω
220μF
C
AV = 2V/V
CLAMPREF
DAC
0.1μF
CVBS
IN2
OUT2
LPF*
75Ω
75Ω
220μF
CVBS1
AV = 2V/V
CLAMPREF
0.1μF
IN3
OUT3
LPF*
75Ω
220μF
CVBS2
AV = 2V/V
CLAMPREF
*LOWPASS FILTER IN MAX9658 ONLY.
Figure 1. AC-Coupled Outputs
Table 1. Quiescent and Average Power Consumption for MAX9657/MAX9658
MEASUREMENT
POWER CONSUMPTION
(mW)
CONDITIONS
Quiescent power consumption
69
No load.
Average power consumption
200
150Ω to ground on each output. 50% flat field signal on
each input.
______________________________________________________________________________________
11
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
MAX9657/MAX9658
Typical Application Circuits
+3.3V
0.1μF
VDD
MAX9657
SHDN
0.1μF
IN0
OUT0
75Ω
0.1μF
75Ω
75Ω
AV = 2V/V
CLAMPREF
0.1μF
IN1
OUT1
75Ω
75Ω
AV = 2V/V
CVBS
INPUTS
0.1μF
75Ω
16x16
CROSSPOINT
CLAMPREF
0.1μF
IN2
OUT2
75Ω
0.1μF
75Ω
75Ω
AV = 2V/V
CLAMPREF
0.1μF
IN3
OUT3
75Ω
AV = 2V/V
0.1μF
75Ω
75Ω
CLAMPREF
GND
NOTE: FOUR MAX9657s ARE REQUIRED BEFORE THE 16x16 CROSSPOINT.
12
______________________________________________________________________________________
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
+3.3V
0.1μF
VDD
MAX9658
SHDN
0.1μF
IN0
OUT0
LPF
75Ω
0.1μF
75Ω
75Ω
AV = 2V/V
CLAMPREF
0.1μF
IN1
OUT1
LPF
75Ω
75Ω
AV = 2V/V
CVBS
INPUTS
0.1μF
75Ω
QUADRUPLE
VIDEO
DECODER
CLAMPREF
0.1μF
IN2
OUT2
LPF
75Ω
0.1μF
75Ω
75Ω
AV = 2V/V
CLAMPREF
0.1μF
IN3
OUT3
LPF
75Ω
AV = 2V/V
0.1μF
75Ω
75Ω
CLAMPREF
GND
______________________________________________________________________________________
13
MAX9657/MAX9658
Typical Application Circuits (continued)
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
MAX9657/MAX9658
Pin Configuration
Chip Information
PROCESS: BiCMOS
IN0 1
+
16 VDD
IN1 2
IN2 3
15 N.C.
MAX9657
MAX9658
14 OUT0
IN3 4
13 OUT1
N.C. 5
12 OUT2
N.C. 6
11 OUT3
N.C. 7
10 SHDN
N.C. 8
9 GND
QSOP
14
______________________________________________________________________________________
Quad Video (Filter) Amplifiers with Input
Sync-Tip Clamps
PACKAGE CODE
DOCUMENT NO.
16 QSOP
E16-4
21-0055
QSOP.EPS
PACKAGE TYPE
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 ____________________ 15
© 2009 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX9657/MAX9658
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
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