MAXIM MAX9532_11

19-4431; Rev 2; 11/11
KIT
ATION
EVALU
E
L
B
AVAILA
DirectDrive Video Amplifier with
Short-to-Battery Protection
Features
DirectDrive ®
The MAX9532
video filter amplifier is
specifically designed to work in harsh environments
such as automobiles. The MAX9532 provides integrated short-to-battery protection, allowing the output of the
device to survive shorts up to 18V.
Maxim’s DirectDrive technology eliminates large output
coupling capacitors and sets the output video black
level near ground. DirectDrive requires an integrated
charge pump and an internal linear regulator to create
a clean negative power supply so that the amplifier can
pull the sync below ground. The charge pump injects
so little noise into the video output that the picture is
visibly flawless.
The MAX9532 features an internal reconstruction filter
that smoothes the steps and reduces the spikes on the
video signal from the video digital-to-analog converter
(DAC). The reconstruction filter typically provides ±1dB
passband flatness of 9.5MHz and 42dB attenuation at
27MHz.
The input of the MAX9532 can be directly connected to
the output of a video DAC. The MAX9532 also features a
transparent input sync-tip clamp, allowing AC-coupling
of input signals with different DC biases.
The MAX9532 features an internal fixed gain of 4V/V. The
input full-scale video signal is nominally 0.5VP-P, and the
output full-scale video signal is nominally 2VP-P.
The short-to-battery protection utilizes an internal switch
in series with the amplifier output. When the MAX9532
detects that the output is short circuited to the battery
voltage, the internal switch is disabled, protecting the
MAX9532 from voltages up to 18V.
The MAX9532 is available in a 3mm x 3mm, 10-pin
µMAX® package and is specified over the -40°C to
+125°C automotive operating temperature range.
o Short-to-Battery Protection on Video Output (Up
to 18V)
o DirectDrive Sets Video Output Black Level Near
Ground
o DirectDrive Eliminates DC-Blocking Capacitors at
the Output
o 3.3V Single-Supply Operation
o Reconstruction Filter with 9.5MHz Passband and
42dB Attenuation at 27MHz
o DC-Coupled Input/Output
o Transparent Input Sync-Tip Clamp
o 4V/V Internal Fixed Gain
Applications
Automotive Infotainment Systems
Ordering Information
PART
PIN-PACKAGE
TEMP RANGE
MAX9532AUB/V+T
10 µMAX
-40°C to +125°C
MAX9532AUB+
10 µMAX
-40°C to +125°C
+Denotes a lead(Pb)-free/RoHS-compliant package.
/V denotes an automotive qualified part.
T = Tape and reel.
Pin Configuration and Functional Diagram/Typical
Application Circuits appear at end of data sheet.
Simplified Block Diagram
MAX9532
500mVP-P VIDEO
JACKSENSE
OUT
IN
2VP-P VIDEO
LPF
AV = 4V/V
TRANSPARENT
CLAMP
0V
LINEAR
REGULATOR
CHARGE
PUMP
DirectDrive is a registered trademark of Maxim Integrated Products, Inc.
µMAX is a registered trademark of Maxim Integrated Prodcuts, Inc.
________________________________________________________________ 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
MAX9532
General Description
MAX9532
DirectDrive Video Amplifier with
Short-to-Battery Protection
ABSOLUTE MAXIMUM RATINGS
VDD to GND ..............................................................-0.3V to +4V
VDD to CPGND .........................................................-0.3V to +4V
CPGND to GND.....................................................-0.1V to +0.1V
IN to GND .................................................................-0.3V to +4V
JACKSENSE to GND........................................The higher of VSS
and -2V to (VSS + 22V)
OUT to GND ............The higher of VSS and -1.5V to (VSS + 22V)
VSS to CPVSS ........................................................-0.1V to +0.1V
Continuous Current
IN, JACKSENSE............................................................±20mA
C1P, C1N, CPVSS ........................................................±50mA
OUT ..............................................................................±50mA
Continuous Power Dissipation (TA = +70°C)
10-Pin µMAX (derate 8.8mW/°C above +70°C) ........707.3mW
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
Soldering Temperature (reflow) .......................................+260°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 = VCPGND = 0V, RL = 100Ω to GND, C1 = C2 = C3 = 1µF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC-COUPLED INPUT
Input Voltage Range
VIN
Guaranteed by output voltage swing
3V < VDD < 3.135V
0
0.5
Guaranteed by output voltage swing
3.135V < VDD < 3.6V
0
0.7
V
Input Current
IIN
VIN = 0.5V
2
Input Resistance
RIN
0.1V ≤ VIN ≤ 0.5V
5
3.3
µA
MΩ
SYNC-TIP CLAMP INPUT
Sync-Tip Clamp Level
VCLP
Input Voltage Range
Sync-tip clamp
-6.2
-1.63
+3.5
Guaranteed by output voltage swing
3V < VDD < 3.135V
0
0.5
Guaranteed by output voltage swing
VDD > 3.135V
0
0.7
Sync Crush
Sync-tip clamp; percentage reduction in
sync pulse (0.15VP-P, 75Ω source
impedance), guaranteed by input clamping
current measurement
Input Clamping Current
Sync-tip clamp
mV
VP-P
2
Max Input Source Resistance
2.3
%
3.3
µA
Ω
300
GENERAL
Supply Voltage Range
VDD
Guaranteed by PSRR
3.0
Quiescent Supply Current
DC Voltage Gain
Output Level
2
AV
Guaranteed by output voltage swing
VIN = 150mV
3.92
3.3
3.6
V
15
23
mA
4.08
V/V
+0.150
V
4
-0.120
_______________________________________________________________________________________
DirectDrive Video Amplifier with
Short-to-Battery Protection
(VDD = 3.3V, VGND = VCPGND = 0V, RL = 100Ω to GND, C1 = C2 = C3 = 1µF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Output Voltage Swing
CONDITIONS
MIN
TYP
MAX
Measured at output, VDD = 3.135V,
VIN = VCLP to (VCLP + 0.7V), RL = 100Ω to
-2V and +2V
2.744
2.8
2.856
Measured at output, VDD = 3V, VIN = VCLP
to (VCLP + 0.5V), RL = 100Ω to -2V and +2V
1.96
VP-P
Output Short-Circuit Current
Output Resistance
ROUT
Short Circuit to Battery Current
Short-to-battery, VOUT = 9V to 16V
Power-Supply Rejection Ratio
3.0V ≤ VDD ≤ 3.6V
Filter
VIN = 0.5VP-P, reference
frequency is 100kHz
2
2.04
90
mA
0.1
Ω
3
46
Attenuation at
5.5MHz
UNITS
78
-1.29
mA
dB
+1
dB
Attenuation at
f = 27MHz
20
42
Differential Gain
DG
5-step modulated staircase, f = 4.43MHz,
RL = 100Ω to -2V and +2V
0.7
%
Differential Phase
DP
5-step modulated staircase, f = 4.43MHz,
RL = 100Ω to -2V and +2V
0.5
deg
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; RL = 100Ω to -2V and +2V
0.5
K%
2T Pulse Response
2T = 200ns, RL = 100Ω to -2V and +2V
0.4
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; RL = 100Ω to -2V and +2V
0.1
K%
Nonlinearity
5-step staircase; RL = 100Ω to -2V and +2V
0.1
%
Group Delay Distortion
100kHz ≤ f ≤ 5MHz, outputs are 2VP-P;
RL = 100Ω to -2V and +2V
13
ns
Glitch Impulse Caused by
Charge Pump Switching
Measured at outputs, RL = 100Ω to -2V and
+2V
40
pVs
Peak Signal to RMS Noise
100kHz ≤ f ≤ 5MHz, RL = 100Ω to -2V and
+2V
64
dB
Power-Supply Rejection Ratio
f = 100kHz, 100mVP-P; RL = 100Ω to -2V
and +2V
47
dB
Output Impedance
f = 5MHz
2
Ω
250
kΩ
JACKSENSE Input Resistance
120
BATTERY DETECTION
Threshold Accuracy
Referred to GND
Video Output Disconnect Time
After detection of short-to-battery
Video Output Connect Time
After short-to-battery has been removed
7.3
8
8.7
20
4.9
10
V
µs
20
ms
_______________________________________________________________________________________
3
MAX9532
ELECTRICAL CHARACTERISTICS (continued)
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 3.3V, VGND = VCPGND = 0V, RL = 100Ω to GND, C1 = C2 = C3 = 1µF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
220
440
660
kHz
CHARGE PUMP
Switching Frequency
fCP
Note 1: All devices are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design.
Typical Operating Characteristics
(VDD = 3.3V, VGND = VCPGND = 0V, video output has RL = 100Ω to GND, C1 = C2 = C3 = 1μF, TA = +25°C, unless otherwise noted.)
SMALL-SIGNAL GAIN FLATNESS
vs. FREQUENCY
0.8
0.6
0.4
-15
-20
-25
-10
0.2
GAIN (dB)
GAIN (dB)
-10
GAIN (dB)
0
-5
0
-0.2
-30
-0.6
-35
-35
-0.8
VIN = 0.025VP-P
-40
VIN = 0.025VP-P
-1.0
0.1
1
10
100
0.1
FREQUENCY (MHz)
NOTE: GAIN VALUES (PLOTTED IN dB) ARE NORMALIZED
VALUES RELATIVE TO THE EXPECTED VALUE OF 4V/V.
0
-0.2
-0.4
100
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
0
-10
VRIPPLE = 100mVP-P
-20
60
-30
40
20
-40
-50
-60
-70
0
-0.6
-80
-20
-0.8
-90
VIN = 0.5VP-P
VIN = 0.5VP-P
-1.0
-100
-40
0.1
1
10
100
FREQUENCY (MHz)
0.1
1
10
FREQUENCY (MHz)
100
0.1
1
10
FREQUENCY (MHz)
NOTE: GAIN VALUES (PLOTTED IN dB) ARE NORMALIZED
VALUES RELATIVE TO THE EXPECTED VALUE OF 4V/V.
4
10
GROUP DELAY vs. FREQUENCY
PSRR (dB)
0.2
1
FREQUENCY (MHz)
NOTE: GAIN VALUES (PLOTTED IN dB) ARE NORMALIZED
VALUES RELATIVE TO THE EXPECTED VALUE OF 4V/V.
80
GROUP DELAY (ns)
0.4
0.1
100
MAX9532 toc05
0.6
10
100
MAX9532 toc04
0.8
1
VIN = 0.5VP-P
-40
FREQUENCY (MHz)
NOTE: GAIN VALUES (PLOTTED IN dB) ARE NORMALIZED
VALUES RELATIVE TO THE EXPECTED VALUE OF 4V/V.
LARGE-SIGNAL GAIN FLATNESS
vs. FREQUENCY
1.0
-20
-25
-0.4
-30
-15
MAX9532 toc06
0
-5
LARGE-SIGNAL GAIN vs. FREQUENCY
5
MAX9532 toc02
1.0
MAX9532 toc01
5
MAX9532 toc03
SMALL-SIGNAL GAIN vs. FREQUENCY
GAIN (dB)
MAX9532
DirectDrive Video Amplifier with
Short-to-Battery Protection
_______________________________________________________________________________________
100
DirectDrive Video Amplifier with
Short-to-Battery Protection
QUIESCENT CURRENT vs. TEMPERATURE
4.018
4.016
14.67
4.014
14.66
GAIN (V/V)
SUPPLY CURRENT (mA)
14.68
MAX9532 toc08
VSS = 3.3V
VIN = 0V
NO LOAD
14.69
DC GAIN vs. TEMPERATURE
4.020
MAX9532 toc07
14.70
14.65
14.64
14.63
4.012
4.010
4.008
4.006
14.62
14.61
4.004
14.60
4.002
4.000
14.59
-40
10
60
110
-40
10
TEMPERATURE (°C)
OUTPUT VOLTAGE vs. INPUT VOLTAGE
0
-1
-2
0
0.2
0.4
0.6
0.8
1.0
1.0
MAX9532 toc10
DIFFERENTIAL GAIN (%)
1
DIFFERENTIAL PHASE (deg)
OUTPUT VOLTAGE (V)
2
-0.2
110
DIFFERENTIAL GAIN AND PHASE
MAX9532 toc09
AV = 4.012V/V
3
60
TEMPERATURE (°C)
0.5
0
f = 3.58MHz
TA = +25°C
-0.5
-1.0
1
2
3
4
6
5
7
DIFFERENTIAL PHASE
1.0
0.5
0
f = 3.58MHz
TA = +25°C
-0.5
-1.0
1
2
3
4
5
6
7
INPUT VOLTAGE (V)
2T RESPONSE
DIFFERENTIAL PHASE (deg)
MAX9532 toc12
MAX9532 toc11
DIFFERENTIAL GAIN (%)
DIFFERENTIAL GAIN AND PHASE
1.0
f = 4.43MHz
TA = +25°C
0.5
0
VIN
100mV/div
-0.5
-1.0
1
2
3
4
6
5
7
DIFFERENTIAL PHASE
1.0
0.5
VOUT
400mV/div
0
f = 4.43MHz
TA = +25°C
-0.5
-1.0
1
2
3
4
5
6
7
100ns/div
_______________________________________________________________________________________
5
MAX9532
Typical Operating Characteristics (continued)
(VDD = 3.3V, VGND = VCPGND = 0V, video output has RL = 100Ω to GND, C1 = C2 = C3 = 1μF, TA = +25°C, unless otherwise noted.)
MAX9532
DirectDrive Video Amplifier with
Short-to-Battery Protection
Typical Operating Characteristics (continued)
(VDD = 3.3V, VGND = VCPGND = 0V, video output has RL = 100Ω to GND, C1 = C2 = C3 = 1μF, TA = +25°C, unless otherwise noted.)
2T RESPONSE
VIDEO TEST SIGNAL
MAX9532 toc13
FIELD SQUARE-WAVE RESPONSE
MAX9532 toc14
MAX9532 toc15
VIN
100mV/div
VIN
200mV/div
VOUT
400mV/div
VOUT
800mV/div
400ns/div
VIN
200mV/div
VOUT
800mV/div
10μs/div
OUTPUT SHORT-TO-BATTERY
RESPONSE
2ms/div
OUTPUT SHORT-TO-BATTERY
RESPONSE
MAX9532 toc16
MAX9532 toc17
VJACKSENSE
10V/div
VJACKSENSE
10V/div
0V
0V
VOUT
500mV/div
VOUT
500mV/div
0V
0V
100μs/div
6
2ms/div
_______________________________________________________________________________________
DirectDrive Video Amplifier with
Short-to-Battery Protection
PIN
NAME
1
VDD
Positive Power Supply. Bypass VDD with a 1µF capacitor to GND.
FUNCTION
2
C1P
Charge-Pump Flying Capacitor Positive Terminal. Connect a 1µF ceramic capacitor from C1P to C1N.
3
CPGND
Charge-Pump Ground. Connect to GND.
Charge-Pump Flying Capacitor Negative Terminal. Connect a 1µF ceramic capacitor from C1P to
C1N.
4
C1N
5
CPVSS
6
VSS
Negative Power Supply. Connect VSS to CPVSS.
OUT
Video Output
7
8
Charge-Pump Negative Power Supply. Bypass CPVSS with a 1µF ceramic capacitor in parallel with a
10nF low ESL capacitor to GND.
JACKSENSE Jack-Sense Input. Connect to the video output connector after the back-termination resistor.
9
GND
10
IN
Ground
Video Input
Detailed Description
The MAX9532 DirectDrive video amplifier with short-tobattery protection features an internal 5-pole
Butterworth lowpass filter with the amplifier configured
with a gain of 4. The MAX9532 accepts DC-coupled or
AC-coupled full-scale input signals of 0.5V P-P .
Integrated short-to-battery protection prevents the
MAX9532 from being damaged when the output is
short circuited to the battery in automotive applications.
DirectDrive
Background
Integrated video filter amplifier circuits operate from a
single supply. The positive power supply usually creates video output signals that are level-shifted above
ground to keep the signal within the linear range of the
output amplifier. For applications where the positive DC
level is not acceptable, a series capacitor can be
inserted in the output connection to eliminate the positive DC level shift. The series capacitor cannot truly
level shift a video signal because the average level of
the video varies with picture content. The series capacitor biases the video output signal around ground, but
the actual level of the video signal can vary significantly
depending upon the RC time constant and the picture
content.
The series capacitor creates a highpass filter. Since the
lowest frequency in video is the frame rate, which is
between 24Hz and 30Hz, the pole of the highpass filter is
ideally an order of magnitude lower in frequency than
the frame rate. Therefore, the series capacitor must
be very large, typically from 220µF to 3000µF. For
space-constrained equipment, the series capacitor is
unacceptable. Changing from a single series capacitor to
a SAG network that requires two smaller capacitors can
only reduce space and cost slightly.
Video Amplifier
When the full-scale video signal from a video DAC is
500mV, the black level of the video signal created by
the video DAC is around 150mV. The MAX9532 shifts
the black level to near ground at the output so that the
active video is above ground and the sync is below
ground. The amplifier needs a negative supply for the
output stage to remain in the linear region when driving
sync below ground.
The MAX9532 includes an integrated charge pump and
linear regulator to create a low-noise negative supply
from the positive supply voltage. The charge pump
inverts the positive supply to create a raw negative voltage that is then fed into the linear regulator filtering out
the charge-pump noise.
Comparison Between DirectDrive Output
and AC-Coupled Output
The actual level of the video signal varies less with a
DirectDrive output than with an AC-coupled output. The
average video signal level changes depending upon
the picture content. With an AC-coupled output, the
average level changes according to the time constant
formed by the series capacitor and series resistance
(usually 150Ω). For example, Figure 1 shows an ACcoupled video signal alternating between a completely
black screen and a completely white screen. Notice the
excursion of the video signal as the screen changes.
_______________________________________________________________________________________
7
MAX9532
Pin Description
MAX9532
DirectDrive Video Amplifier with
Short-to-Battery Protection
INPUT
500mV/div
INPUT
500mV/div
0V
OUTPUT
500mV/div
2ms/div
0V
OUTPUT
1V/div
2ms/div
Figure 1. AC-Coupled Output
Figure 2. DirectDrive Output
With the DirectDrive amplifier, the black level is held at
ground. The video signal is constrained between
-0.3V to +0.7V. Figure 2 shows the video signal from a
DirectDrive amplifier with the same input signal as the
AC-coupled system.
prototyping and applications where the amplifier output
can be directly shorted to ground.
The MAX9532 features an internal five-pole, Butterworth
lowpass filter to condition the video signal. The reconstruction filter smoothes the steps and reduces the
spikes created whenever the DAC output changes
value. In the frequency domain, the steps and spikes
cause images of the video signal to appear at multiples
of the sampling clock frequency. The reconstruction filter typically provides ±1dB passband flatness of
9.5MHz and 42dB attenuation at 27MHz.
To protect the device from output short circuits to voltages higher than the supply voltage VDD, the MAX9532
utilizes an internal switch in series with the amplifier output. When the JACKSENSE input detects that the output connector of the circuit is shorted to the battery
voltage (up to 18V) higher than the internal 8V threshold, an internal comparator disables the switch in 10µs
(typ) preventing the MAX9532 from being damaged.
After the output is shorted to a battery, the output
immediately resumes normal operation when the short
is removed within 1ms. When the output is shorted to
the battery for longer than 1ms, the output resumes normal operation 10ms after the short is removed.
Transparent Sync-Tip Clamp
Applications
Video Reconstruction Filter
The MAX9532 contains an integrated, transparent synctip clamp. When using a DC-coupled input, the sync-tip
clamp does not affect the input signal as long as the
input signal remains above ground. When using an ACcoupled input, the sync-tip clamp automatically clamps
the input signal to ground, preventing the input signal
from going lower. A low current of 2µA pulls down on
the input to prevent an AC-coupled signal from drifting
outside the input range of the device.
Short-Circuit
and Short-to-Battery Protection
The MAX9532 typical operating circuit includes a 50Ω
or 75Ω back-termination resistor that limits short-circuit
current when an external short is applied to the video
output. The MAX9532 also features an internal output
short-circuit protection to prevent device damage in
8
Power Consumption
Quiescent power consumption is defined when the
MAX9532 is operating without load. In this case, the
MAX9532 consumes about 47.355mW. Average power
consumption, when the MAX9532 drives a 100Ω and
150Ω load to ground with a 50% flat field, is about
51.596mW and 49.513mW, respectively. Table 1 shows
the power consumption with different video signals.
Notice that the two extremes in power consumption
occur with a video signal that is all black and a video
signal that is all white. The power consumption with
75% color bars and 50% flat field lies in between the
extremes.
_______________________________________________________________________________________
DirectDrive Video Amplifier with
Short-to-Battery Protection
IMAGE
PROCESSOR
ASIC
0V TO 1V
MAX9532
GENERIC 2V/V CONFIGURATION
IMAGE
PROCESSOR
ASIC
MAX9532
0V TO 0.5V
DAC
LPF
2V/V
DAC
2VP-P
150Ω
Figure 3. Typically, a Video DAC Generates a 1VP-P Signal
Across a 150Ω Resistor Connected to Ground
LPF
4V/V
2VP-P
75Ω
Figure 4. Video DAC Generates a 0.5VP-P Signal Across a 75Ω
Resistor Connected to Ground
Table 1. Power Consumption of the MAX9532 with Different Video Signals
MAX9532 POWER CONSUMPTION (mW)
WITH 150Ω LOAD
MAX9532 POWER CONSUMPTION (mW)
WITH 100Ω LOAD
All Black Screen
51.236
53.978
All White Screen
57.077
65.399
VIDEO SIGNAL
75% Color Bars
53.074
57.486
50% Flat Field
49.513
51.596
Note: The supply voltage is 3.3V.
Interfacing to Video DACs that Produce
Video Signals Higher than 0.5VP-P
Devices designed to generate 1VP-P video signals at
the output of the video DAC can work with the
MAX9532. Most video DACs source current into a
ground-referenced resistor, which converts the current
into a voltage. Figure 3 shows a video DAC that creates
a video signal from 0V to 1V across a 150Ω resistor.
With a gain of 2V/V, the following video filter produces a
2VP-P output.
The MAX9532 accepts input signals that are 0.5VP-P
nominally. The video DAC in Figure 3 can be made to
work with the MAX9532 by scaling down the 150Ω
resistor to a 75Ω resistor, as shown in Figure 4. The
75Ω resistor is one-half the size of the 150Ω resistor,
resulting in a video signal that is one-half the amplitude.
Video Source with a Positive DC Bias
In some applications, the video source generates a signal with a positive DC voltage bias, i.e., the sync tip of
the signal is well above ground. Figure 5 shows an
example in which the outputs of the luma (Y) DAC and
the chroma (C) DAC are connected together. Since the
DACs are current-mode, the output currents sum
together into the resistor, which converts the resulting
current into a voltage representing a composite video
signal.
When the chroma DAC is connected to an independent
output resistor to ground, the chroma signal, which is a
carrier at 3.58MHz for NTSC or at 4.43MHz for PAL,
generates a positive DC bias to keep the signal above
ground at all times. When the luma DAC is connected
to an independent output resistor to ground, the luma
signal usually does not have a positive DC bias, and
the sync tip is at approximately ground. When the chroma and luma signals are added together, the resulting
composite video signal generates a positive DC bias.
Therefore, the signal must be AC-coupled into the
MAX9532 because the composite video signal is above
the nominal 0V to 0.7V DC-coupled input range.
Video Signal Routing
Minimize the length of the PCB trace between the output of the video DAC and the input of the MAX9532 to
reduce coupling of external noise into the video signal.
If possible, shield the PCB trace.
_______________________________________________________________________________________
9
MAX9532
DirectDrive Video Amplifier with
Short-to-Battery Protection
VDD
VIDEO
ASIC
DAC
MAX9532
JACKSENSE
AV = 4V/V
Y
OUT
IN
AMP
LPF
50Ω
0.1μF
DAC
C
50Ω
3.3V
CLAMP
VDD
C3
1μF
LINEAR
REGULATOR
DC
LEVEL SHIFT
CHARGE PUMP
GND
CPGND C1P
C1N
CPVSS VSS
C2
1μF || 10nF
Figure 5. Luma (Y) and Chroma (C) Signals are Added Together to Create a Composite Video Signal, Which is AC-Coupled into the
MAX9532
Power-Supply Bypassing
and Ground Management
The MAX9532 operates from a 3V to 3.6V single supply
and requires proper layout and bypassing. For the best
performance, place the components as close as possible to the device.
Proper grounding improves performance and prevents
any switching noise from coupling into the video signal.
10
Bypass the analog supply (VDD) with a 1µF capacitor to
GND, placed as close as possible to the device.
Bypass CPVSS to GND with a 1µF ceramic capacitor in
parallel with a 10nF low-ESR capacitor. The bypass
capacitors should be placed as close as possible to
the device.
______________________________________________________________________________________
DirectDrive Video Amplifier with
Short-to-Battery Protection
VDD
VIDEO
ASIC
MAX9532
JACKSENSE
AV = 4V/V
OUT
IN
DAC
AMP
LPF
50Ω
50Ω
3.3V
VDD
TRANSPARENT
CLAMP
C3
1μF
DC
LEVEL SHIFT
LINEAR
REGULATOR
CHARGE PUMP
GND
CPGND C1P
C1N
C1
1μF
CPVSS VSS
C2
1μF || 10nF
Chip Information
Pin Configuration
PROCESS: BiCMOS
TOP VIEW
+
VDD 1
C1P
10 IN
2
MAX9532
9
GND
CPGND
3
8
JACKSENSE
C1N
4
7
OUT
CPVSS
5
6
VSS
μMAX
______________________________________________________________________________________
11
MAX9532
Functional Diagram/Typical Application Circuits
(DC-Coupled Input/Inactive Input Clamp)
MAX9532
DirectDrive Video Amplifier with
Short-to-Battery Protection
Package Information
For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or
“-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains
to the package regardless of RoHS status.
PACKAGE TYPE
PACKAGE CODE
OUTLINE NO.
LAND PATTERN NO.
10 µMAX
U10+2
21-0061
90-0330
α
α
12
______________________________________________________________________________________
DirectDrive Video Amplifier with
Short-to-Battery Protection
REVISION
NUMBER
REVISION
DATE
0
2/09
Initial release
1
8/11
Added automotive qualified part
1
2
11/11
Updated part number to show tape and reel designation
1
DESCRIPTION
PAGES CHANGED
—
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 ____________________ 13
© 2011 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX9532
Revision History