General Description
The MAX9505 filters and amplifies standard-definition
video signals. Maxim’s DirectDrive™ technology eliminates large output-coupling capacitors and sets the
video black level to ground. An internal reconstruction
filter smoothes the steps and reduces the spikes on the
video signal from the video digital-to-analog converter
(DAC). The input of the MAX9505 can be directly connected to the output of a DAC. The MAX9505 provides
a compact, integrated, and low-power solution.
The reconstruction filter typically has 3dB attenuation at
9MHz and 50dB attenuation at 27MHz, and ±1dB passband flatness to 5.5MHz.
Maxim’s DirectDrive uses an integrated charge pump
and a linear regulator to create a negative power supply
to drive the sync below ground. The charge pump injects
so little noise into the video output that the picture is visibly flawless.
The MAX9505 features an internal 1.7Ω analog switch
that interfaces with a 4-pole multimedia jack. This
switch allows one of the poles to be set as a video
input, a video output, or a microphone input.
The MAX9505 is offered in space-saving 16-pin QSOP
and 16-pin TQFN packages and is specified over the
-40°C to +85°C extended temperature range.
Applications
Mobile Phones/Smartphones
Space-Constrained, Low-Power Audio/Video
Portable Devices
Features
♦ DC-Coupled Output
♦ Direct Connection to Video DAC
♦ Video Output Black Level Set to Ground
♦ Video Reconstruction Filter with 50dB
Attenuation at 27MHz
♦ 6dB Gain
♦ 1.7Ω R
ON
Analog Switch
♦ 10nA Shutdown Supply Current
♦ 2.7V to 3.6V Single-Supply Operation
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
0 TO 50mV
-0.1V TO
+0.1V
MAX9505
AMP
LINEAR
REGULATOR
CHARGE
PUMP
BUFFER
VIDOUT
VIDIN
6dB
S
OUT
S
IN
LOWPASS
FILTER
0V
0V
Block Diagram
19-3675; Rev 1; 8/05
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.
PART*
PINPACKAGE
PKG CODE
TOP MARK
MAX9505EEE 16 QSOP E16-4 —
MAX9505ETE 16 TQFN T1633-4 ACW
Functional Diagram/Typical Operating Circuit and Pin
Configurations appear at end of data sheet.
*All devices are specified over the -40°C to +85°C operating
temperature range.
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VDD= CPVDD= MODE1 = 3.0V, MODE0 = SGND = GND = CPGND = 0V, C1 = C2 = C3 = C4 = 1µF, R
BIAS
= 100kΩ, TA= T
MIN
to
T
MAX
. RL= 150Ω to SGND, unless otherwise noted. V
VIDIN
= 286mV, gain = 6dB. Typical values are at VDD= CPV
DD
= MODE1 = 3.0V,
T
A
= +25°C, unless otherwise noted.) (Note 1)
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.
VDDto SGND............................................................-0.3V to +4V
VIDIN to SGND .........................................................-0.3V to +4V
BIAS to SGND ............................................-0.3V to (V
DD
+ 0.3V)
MODE0, MODE1 to SGND .......................................-0.3V to +4V
S
IN
, S
OUT
, VIDOUT to SGND (The greater of VSSand -2V)
to (V
DD
+ 0.3V)
CPV
DD
to CPGND ....................................................-0.3V to +4V
C1P, C1N, CPV
SS
.............................Capacitor Connection Only
CPGND, SGND, GND............................................-0.1V to +0.1V
CPV
SS
to V
SS ..................................................................
-0.1V to +0.1V
VIDOUT Short Circuit to V
DD
, SGND
and the Greater of (V
SS
and -2V) ...........................Continuous
Continuous Current
VIDIN, BIAS, MODE0, MODE1, S
IN
, S
OUT
...................±20mA
Continuous Power Dissipation (T
A
= +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C)...........667mW
16-Pin TQFN (derate 15.6mW/°C above +70°C) .......1349mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Voltage Range
V
DD
,
CPV
DD
Guaranteed by DC voltage gain and
quiescent supply current
2.7 3.6 V
Quiescent Supply Current I
DD
VDD = 3.6V (IDD = I
VDD
+ I
CPVDD
, RL = ∞)1215mA
Shutdown Supply Current I
SHDN
VDD = 3.6V (I
SHDN
= I
VDD
+ I
CPVDD
),
SHDN = SGND
1µA
Bias Voltage V
BIAS
1V
VIDEO AMPLIFIER
Guaranteed by DC voltage gain,
V
DD
= 2.7V
Input Voltage Range
Guaranteed by DC voltage gain, V
DD
= 3V
V
Input Current I
IN
VDD = 2.7V
µA
Input Resistance R
IN
1MΩ
DC Voltage Gain (Note 2) A
V
VDD = 2.7V to 3.6V 5.5 6 6.5 dB
Output Black Level (Note 3) VDD = 2.7V
0
V
Output Voltage Swing
V
P-P
Output Short-Circuit Current I
SC
Sinking or sourcing 50 mA
Output Resistance R
OUT
Ω
Shutdown Output Impedance MODE1 = MODE0 = SGND 4 kΩ
MODE1 = MODE0 = V
DD
VIDOUT Leakage Current
MODE1 = SGND and MODE0 = V
DD
µA
V
RANGE
-0.10 +1.05
-0.10 +1.28
-2.5 +2.5
Guaranteed by DC voltage gain, VDD = 2.7V 2.162
Guaranteed by DC voltage gain, VDD = 3V 2.594
-0.1
0.01
+0.1
0.01
0.01
0.01
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VDD= CPVDD= MODE1 = 3.0V, MODE0 = SGND = GND = CPGND = 0V, C1 = C2 = C3 = C4 = 1µF, R
BIAS
= 100kΩ, TA= T
MIN
to
T
MAX
. RL= 150Ω to SGND, unless otherwise noted. V
VIDIN
= 286mV, gain = 6dB. Typical values are at VDD= CPV
DD
= MODE1 = 3.0V,
T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
CONDITIONS
UNITS
ANALOG SWITCH
MODE1 = V
DD
1.7 4.4
On-Resistance R
ON
MODE0 = VDD,
I
SIN
= 10mA
1.2 2.5
Ω
MODE1 = V
DD
0.5 0.9
On-Resistance Flatness (Note 4)
MODE0 = VDD,
0.3 0.5
Ω
S
OUT
Off-Leakage Current
(Note 5)
MODE0 = SGND, VDD = 3.6V, V
SIN
= 0.3V,
3.3V, V
SOUT
= 3.3V, 0.3V
-1 +1 nA
SIN On-Leakage Current (Note 5)
MODE0 = VDD, VDD = 3.6V, V
SIN
= 0.3V,
3.3V, V
SOUT
= 3.3V, 0.3V
-1 +1 nA
Turn-On Time
V
SIN
= 1.5V, RL = 300Ω, CL = 35pF,
Figure 1; V
IH
= 1.5V, VIL = 0V
35 60 ns
Turn-Off Time
V
SIN
= 1.5V; RL = 300Ω, CL = 35pF,
Figure 1; V
IH
= 1.5V, VIL = 0V
50 80 ns
Charge Injection
V
GEN
= 1.5V, R
GEN
= 0Ω, CL = 1nF,
Figure 2
20 pC
MODE0 = SGND, f = 10MHz;
V
SOUT
= 1V
P-P
, RL = 50Ω, CL = 5pF
30
Off-Isolation
MODE0 = SGND, f = 1MHz; V
SOUT
= 1V
P-P
,
R
L
= 50Ω, CL = 5pF
50
dB
On-Channel -3dB Bandwidth
MODE0 = V
DD
, signal = 0dBm, RL = 50Ω,
C
L
= 5pF
MHz
Total Harmonic Distortion MODE0 = VDD, V
SIN
= 2V
P-P
, RL = 600Ω
%
S
OUT
Off-Capacitance MODE0 = SGND, f = 1MHz 18 pF
Switch On-Capacitance MODE0 = VDD, f = 1MHz 60 pF
CROSSTALK (VIDEO TO AUDIO)
VIDIN to S
IN
MODE1 = MODE0 = VDD, f = 20kHz,
1V
P-P
at VIDIN
dB
VIDOUT to S
IN
MODE1 = VDD, MODE0 = SGND,
f = 20kHz, 2V
P-P
at VIDOUT
85 dB
CHARGE PUMP
Switching Frequency
300 kHz
LOGIC SIGNALS (MODE0, MODE1)
Logic-Low Threshold V
IL
VDD = 2.7V to 3.6V 0.5 V
Logic-High Threshold V
IH
VDD = 2.7V to 3.6V 1.5 V
Logic Input Current I
IL
1µA
SYMBOL
MIN TYP MAX
MODE1 = SGND
I
= 10mA, VDD = 3V
SIN
MODE1 = SGND
150 250
200
0.025
100
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
4 _______________________________________________________________________________________
AC ELECTRICAL CHARACTERISTICS
(V
DD
= CPV
DD
= MODE1 = 3.0V, MODE0 = SGND = GND = CPGND = 0V, C1 = C2 = C3 = C4 = 1µF, R
BIAS
= 100kΩ, TA= T
MIN
to
T
MAX
. RL = 150Ω to SGND, unless otherwise noted. V
VIDIN
= 286mV, gain = 6dB. Typical values are at VDD= CPV
DD
= MODE1 = 3.0V,
T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Passband Flatness VDD = 2.7V, f = 100kHz to 5.5MHz -1 0 +1 dB
f = 9.1MHz 3
Attenuation
V
DD
= 2.7V,
VIDOUT= 2V
P-P
, attenuation
is referred to 100kHz
f = 27MHz 35 50
dB
Power-Supply Rejection Ratio PSRR f = 100kHz 62 dB
Output Impedance Z
OUT
f = 5MHz 0.5 Ω
Differential Gain Error DG NTSC, VIDOUT = 2V
P-P
0.1 %
Differential Phase Error DP NTSC, VIDOUT = 2V
P-P
0.2
degrees
2T Pulse-to-Bar K Rating
2T = 250ns, bar time is 18µs, the beginning
2.5% and the ending 2.5% of the bar time
are ignored
K%
2T Pulse Response 2T = 250ns 0.3 K%
2T Bar Response
2T = 250ns, bar time is 18µs, the beginning
2.5% and the ending 2.5% of the bar time
are ignored
0.7 K%
Nonlinearity 5-step staircase 0.2 %
Group Delay Distortion D
Dt
100kHz to 5.5MHz 10 ns
VIDOUT Capacitive-Load Stability
C
L
V
OUT
= 2V
P-P
, no sustained oscillations 20 pF
Peak Signal-to-RMS Noise SNR 100kHz to 5.5MHz 64 dB
Enable Time t
ON
VIDIN = 0.5V, VIDOUT settled to within 1%
of the final voltage
0.2 ms
Disable Time t
OFF
VIDIN = 0.5V, VIDOUT settled to below 1%
of the output voltage
0.1 ms
Note 1: All devices are 100% production tested at TA= +25°C. Specifications over temperature are guaranteed by design.
Note 2: Voltage gain (A
V
) is a two-point measurement in which the output voltage swing is divided by the input voltage swing.
Note 3: With an output load attached, this offset will directly contribute to quiescent current.
Note 4: Flatness is defined as the difference between the maximum and minimum value of on-resistance as measured over the
specified analog signal ranges.
Note 5: Guaranteed by design.
-0.3
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
_______________________________________________________________________________________ 5
Timing Diagrams
V
DD
V
DD
S
IN
S
OUT
MODE0
SGND
LOGIC
INPUT
V
NO
V
OUT
R
L
C
L
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
V
OUT
= V
NO (RL
/ (RL + RON))
MODE0
SWITCH OUTPUT
0V
V
IL
0.9 x V
OUT
50%
V
IH
0.9 x V
OUT
V
OUT
t
ON
t
OFF
tR < 5ns
t
F
< 5ns
Figure 1. Analog Switch Turn-On/Off Time
V
DD
V
DD
S
IN
S
OUT
SGND
V
OUT
C
L
MODE0
R
GEN
V
GEN
VIL TO V
IH
IN
∆V
OUT
OFFOFF
ON
V
OUT
IN
Q = (∆V
OUT
) (CL)
Figure 2. Charge Injection
Typical Operating Characteristics
(VDD= CPV
DD
= MODE1 = 3.0V, MODE0 = SGND = GND = CPGND = 0V, no load, C1 = C2 = C3 = C4 = 1µF, R
BIAS
= 100kΩ, TA=
T
MIN
to T
MAX
. R
IN
= 150Ω to SGND, unless otherwise noted. V
VIDIN
= 286mV, gain = 6dB. Typical values are at TA= +25°C, unless
otherwise noted.)
SMALL-SIGNAL GAIN vs. FREQUENCY
MAX9505 toc01
FREQUENCY (MHz)
GAIN (dB)
101
-70
-60
-50
-40
-30
-20
-10
0
10
20
-80
0.1 100
V
VIDOUT
= 100mV
P-P
GAIN = 6dB
SMALL-SIGNAL GAIN FLATNESS
vs. FREQUENCY
MAX9505 toc02
FREQUENCY (MHz)
GAIN FLATNESS (dB)
1
4
5
6
7
8
3
0.1 10
V
VIDOUT
= 100mV
P-P
GAIN = 6dB
LARGE-SIGNAL GAIN vs. FREQUENCY
MAX9505 toc03
FREQUENCY (MHz)
GAIN (dB)
101
-70
-60
-50
-40
-30
-20
-10
0
10
20
-80
0.1 100
V
VIDOUT
= 2V
P-P
GAIN = 6dB
LARGE-SIGNAL GAIN FLATNESS
vs. FREQUENCY
MAX9505 toc04
FREQUENCY (MHz)
GAIN FLATNESS (dB)
1
4
5
6
7
8
3
0.1 10
V
VIDOUT
= 2V
P-P
GAIN = 6dB
GROUP DELAY
MAX9505 toc05
FREQUENCY (MHz)
GROUP DELAY (ns)
101
25
50
75
100
125
150
0
0.1 100
V
VIDOUT
= 2V
P-P
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
MAX9505 toc06
FREQUENCY (MHz)
PSRR (dB)
10.1
-100
-80
-60
-40
-20
0
20
-120
0.01 10
QUIESCENT SUPPLY CURRENT
vs. TEMPERATURE (VIDEO MODE)
MAX9505 toc07
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
603510-15
11
12
13
14
10
-40 85
MODE0 = SGND, MODE1 = V
DD
VOLTAGE GAIN vs. TEMPERATURE
MAX9505 toc08
TEMPERATURE (°C)
VOLTAGE GAIN (dB)
603510-15
5.9
6.0
6.1
6.2
5.8
-40 85
OUTPUT VOLTAGE vs. INPUT VOLTAGE
MAX9505 toc09
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
2.31.81.30.80.3
0
1
2
3
4
-1
-0.2 2.8
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
6 _______________________________________________________________________________________
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
_______________________________________________________________________________________ 7
Typical Operating Characteristics (continued)
(VDD= CPV
DD
= MODE1 = 3.0V, MODE0 = SGND = GND = CPGND = 0V, no load, C1 = C2 = C3 = C4 = 1µF, R
BIAS
= 100kΩ, TA=
T
MIN
to T
MAX
. R
IN
= 150Ω to SGND, unless otherwise noted. V
VIDIN
= 286mV, gain = 6dB. Typical values are at TA= +25°C, unless
otherwise noted.)
DIFFERENTIAL GAIN AND PHASE
MAX9505 toc10
DIFFERENTIAL GAIN (%)
5432
0.2
0.1
-0.1
0
0.3
-0.3
16
DIFFERENTIAL PHASE (deg)
5432
0.2
0.1
-0.2
-0.1
0
0.3
-0.3
16
-0.2
2T RESPONSE
MAX9505 toc11
VIDIN
200mV/div
VIDOUT
400mV/div
100ns/div
12.5T RESPONSE
MAX9505 toc12
VIDIN
250mV/div
VIDOUT
500mV/div
400ns/div
OUT RESPONSE
TO NTC-7 VIDEO TEST SIGNAL
MAX9505 toc13
VIDIN
500mV/div
VIDOUT
1V/div
10µs/div
0V
0V
FIELD SQUARE-WAVE RESPONSE
MAX9505 toc14
VIDIN
500mV/div
VIDOUT
1V/div
2ms/div
0V
0V
ON-RESISTANCE vs. V
SOUT
MAX9505 toc15
V
SOUT
(V)
ON-RESISTANCE (Ω)
3.02.41.81.20.6
1
2
3
4
5
0
0 3.6
MODE0 = MODE1 = V
DD
VDD = 2.7V
VDD = 3.0V
VDD = 3.6V
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
8 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(VDD= CPV
DD
= MODE1 = 3.0V, MODE0 = SGND = GND = CPGND = 0V, no load, C1 = C2 = C3 = C4 = 1µF, R
BIAS
= 100kΩ, TA=
T
MIN
to T
MAX
. R
IN
= 150Ω to SGND, unless otherwise noted. V
VIDIN
= 286mV, gain = 6dB. Typical values are at TA= +25°C, unless
otherwise noted.)
CHARGE INJECTION vs. V
SOUT
MAX9505 toc18
V
SOUT
(V)
CHARGE INJECTION (pC)
2.52.00.5 1.0 1.5
-5
0
5
10
15
20
25
30
-10
0 3.0
CL = 1nF
SUPPLY CURRENT vs. TEMPERATURE
(NORMAL SWITCH MODE)
MAX9505 toc19
TEMPERATURE (°C)
SUPPLY CURRENT (nA)
603510-15
30
60
90
120
150
0
-40 85
VDD = 3V
MODE0 = MODE1 = V
DD
ON-RESISTANCE vs. V
SOUT
MAX9505 toc16
V
SOUT
(V)
ON-RESISTANCE (Ω)
2.52.01.51.00.5
1
2
3
4
5
0
0 3.0
MODE0 = MODE1 = V
DD
TA = +85°C
TA = +25°C
TA = -40°C
SWITCH LEAKAGE CURRENT
vs. TEMPERATURE
MAX9505 toc17
TEMPERATURE (°C)
LEAKAGE CURRENT (pA)
603510-15
200
400
600
800
1000
0
-40 85
SIN ON-LEAKAGE
S
OUT
OFF-LEAKAGE
ON-RESPONSE, OFF-ISOLATION,
CROSSTALK vs. FREQUENCY
MAX9505 toc20
FREQUENCY (MHz)
LOSS (dB)
10.1
-100
-80
-60
-40
-20
0
20
-120
0.01 10
ON-RESPONSE
VIDOUT CROSSTALK
VIDIN CROSSTALK
OFF-ISOLATION
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX9505 toc21
FREQUENCY (kHz)
THD+N (%)
1010.1
0.01
0.1
1
10
0.001
0.01 100
V
SIN
= 2V
P-P
RL = 600Ω
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
_______________________________________________________________________________________ 9
Detailed Description
The MAX9505 completely eliminates the need for
capacitors in the video output by using Maxim’s
DirectDrive technology that includes an inverting
charge pump and linear regulator. The charge pump
and linear regulator create a clean negative supply
allowing the amplifier output to swing below ground.
The amplifier output can swing both positive and negative so that the video signal black level can be placed
at ground. The MAX9505 features a six-pole,
Butterworth filter to perform reconstruction filtering on
the video input signal from the DAC.
DirectDrive
Background
Integrated video filter/amplifier circuits operating from a
single, positive supply usually create video output signals that are level-shifted above ground to keep the
signal within the linear range of the output amplifier. For
applications in which the positive DC level shift of the
video signal is not acceptable, a series capacitor can
be inserted in the output connection in an attempt 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
can be between 24Hz and 30Hz, the pole of the highpass filter should ideally be 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.
The series capacitor in the usual output connection
also prevents damage to the output amplifier if the connector is shorted to a supply or to ground. While the
output connection of the MAX9505 does not have a
series capacitor, the MAX9505 will not be damaged if
the connector is shorted to a supply or to ground (see
the Short-Circuit Protection section).
Pin Description
PIN
QSOP TQFN
NAME
FUNCTION
115VSSNegative Power Supply. Connect to CPVSS.
216
Charge-Pump Negative Power Supply. Bypass with a 1µF capacitor to CPGND.
31C1N
Charge-Pump Flying Capacitor Negative Terminal. Connect a 1µF capacitor from C1P to C1N.
42
Charge-Pump Power Ground
53C1P Charge-Pump Flying Capacitor Positive Terminal. Connect a 1µF capacitor from C1P to C1N.
64
Charge-Pump Positive Power Supply. Bypass with a 1µF capacitor to CPGND.
75BIAS Common-Mode Voltage. Connect a 100kΩ resistor from BIAS to SGND.
86
Signal Ground. Connect to GND.
97VIDIN Video Input
10 8
Mode Logic Input 0. See Table 1.
11 9
Mode Logic Input 1. See Table 1.
12 10 GND Ground. Connect to SGND.
13 11 V
DD
Positive Power Supply. Bypass with a 1µF capacitor to SGND.
14 12 S
OUT
Analog Switch Output
15 13
Video Output
16 14 S
IN
Analog Switch Input
—EPEPExposed Paddle. Connect to GND.
CPV
SS
CPGND
CPV
DD
SGND
MODE0
MODE1
VIDOUT
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
10 ______________________________________________________________________________________
Video Amplifier
Typically, the black level of the video signal created by
the video DAC is around 300mV. The MAX9505 shifts
the black level to ground at the output. Therefore, the
active video is above ground, and sync is below
ground. The amplifier needs a negative supply for its
output stage to remain in its linear region when driving
sync below ground.
The MAX9505 has 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, which outputs -2V. The
linear regulator filters 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 an AC-coupled output. The
video signal average can change greatly depending
upon the picture content. With an AC-coupled output,
the average will change according to the time constant
formed by the series capacitor and series resistance
(usually 150Ω). For example, Figure 3 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.
With the DirectDrive amplifier, the black level is held at
ground. The video signal is constrained between
-0.3V to +0.7V. Figure 4 shows the video signal from a
DirectDrive amplifier with the same input signal as the
AC-coupled system.
Analog Switch
The MAX9505 features an internal 4.4Ω (max) analog
normally open switch that interfaces with a 4-pole multimedia jack in which one of the poles can be set to a
video input, a video output, or a microphone input. The
switch has three modes of operation: open, normal
switch, and extended range switch. In normal switch
mode, the analog range is from 0V to VDD. In extendedrange switch mode, the analog range is from -2V to
V
DD.
Logic inputs MODE1 and MODE0 control the ana-
log switch operating modes (Table 1).
Video Reconstruction Filter
Before the video signal from the DAC can be amplified,
it must be lowpass filtered to smooth the steps and to
reduce 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. The MAX9505 contains
a six-pole Butterworth lowpass filter. The passband
extends to 5.5MHz, and the minimum attenuation is
35dB at 27MHz.
Operating Modes
The MAX9505 uses two logic inputs to set the device
into one of the following modes: 1) shutdown mode, 2)
extended-range switch mode, 3) video output mode,
and 4) normal switch mode.
In video output mode, the video circuitry is on, the
charge pump is on, and the analog switch is open. In
normal switch mode, the analog switch is closed, and
the video circuitry and charge pump are off. In the
extended-range switch mode, the charge pump is on
and the analog switch is closed. Shutdown mode
reduces the supply current to 10nA typically (see Table
1 and Typical Application Circuits).
INPUT
500mV/div
OUTPUT
500mV/div
2ms/div
0V
0V
Figure 3. AC-Coupled Output
INPUT
500mV/div
OUTPUT
500mV/div
2ms/div
0V
0V
Figure 4. DirectDrive Output
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
______________________________________________________________________________________ 11
Short-Circuit Protection
The MAX9505 typical operating circuit includes a 75Ω
back-termination resistor that limits short-circuit current if
an external short is applied to the video output. The
MAX9505 features internal output, short-circuit protection
to prevent device damage in prototyping and applications where the amplifier output can be directly shorted.
Shutdown
The MAX9505 features a low-power shutdown mode for
battery-powered/portable applications. Shutdown
reduces the quiescent current to less than 10nA. Setting
MODE1 and MODE0 low disables the outputs and
places the MAX9505 into a low-power shutdown mode.
In shutdown mode the amplifier, charge pump, and linear regulator are turned off and the video output resistance is 4kΩ.
Applications Information
Power-Supply Bypassing and Ground
Management
The MAX9505 operates from a 2.7V to 3.6V single supply and requires proper layout and bypassing. For the
best performance, place the components as close to
the device as possible.
Proper grounding improves performance and prevents
any switching noise from coupling into the video signal.
Connect GND and SGND together at a single point on
the PC board. Route all traces that carry switching transients away from SGND. Return SGND to the lowest
impedance ground available. Route CPGND and all
traces carrying switching transients away from SGND,
GND, and other traces and components in the video
signal path. Bypass the analog supply (VDD) with a 1µF
capacitor to SGND, placed as close to the device as
possible. Bypass the charge-pump supply (CPV
DD
)
with a 1µF capacitor to CPGND, placed as close to the
device as possible. Connect CPVSSto V
SS
and bypass
with a 1µF capacitor to CPGND as close to the device
as possible.
Table 1. Operating Modes
OPERATING MODE
MODE1
MODE0
VIDEO
CHARGE
PUMP
ANALOG
COMMENTS
Shutdown Mode 0 0 Off Off Open
Video output is 4kΩ and analog
switch is open
Extended Range Switch
Mode
01Off On Closed
Video output is high impedance.
Analog switch range is from -2V
to V
DD
.
Video Output Mode 1 0 On On Open
Video output is in normal operation.
Analog switch is open.
Normal Switch Mode 1 1 Off Off Closed
Video output is high impedance.
Analog switch range is from SGND
to V
DD
.
CIRCUIT
SWITCH
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
12 ______________________________________________________________________________________
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
V
SS
S
IN
VIDOUT
S
OUT
V
DD
GND
MODE1
MODE0
VIDIN
QSOP
CPV
SS
C1N
CPV
DD
CPGND
C1P
BIAS
SGND
MAX9505
12
13
14
15
16
8
7
6
5
11 10 9
1234
S
OUTVDD
GND
MODE1
MODE0
VIDIN
SGND
BIAS
S
IN
V
SS
CPV
SS
C1N
CPGND
C1P
CPV
DD
VIDOUT
TOP VIEW
MAX9505
3mm x 3mm TQFN
Pin Configurations
MAX9505
LOGIC
CONTROL
LINEAR
REGULATOR
CHARGE PUMP
RECONSTRUCTION
FILTER
1V
VIDEO
AMP
BUFFER
DC
LEVEL SHIFT
75Ω
VIDOUT
6dB
CPGND C1P C1N CPV
SSVSS
C1
1µF
C2
1µF
100kΩ
BIAS
V
DD
C4
1µF
C3
1µF
CPV
DD
V
DD
GND
SGND
VIDIN
MODE1
DAC
VIDEO
ASIC
MODE0
150Ω
1
2
3
4
VIDEO OUT
AUDIO OUT LEFT
AUDIO OUT RIGHT
GROUND
4-POLE MULTIMEDIA JACK
VIDEO OUTPUT MODE
Functional Diagram/Typical Operating Circuits
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
______________________________________________________________________________________ 13
MAX9505
LOGIC
CONTROL
1V
75Ω
VIDOUT
CPGND C1P C1N CPV
SSVSS
C1
1µF
C2
1µF
100kΩ
BIAS
V
DD
C4
1µF
C3
1µF
CPV
DD
V
DD
GND
SGND
MODE1
BASEBAND
IC
MODE0
1
2
3
4
MIC INPUT
AUDIO OUT LEFT
AUDIO OUT RIGHT
GROUND
4-POLE MULTIMEDIA JACK
MIC
AMP
S
IN
S
OUT
2.8V FROM LDO
1µF
2kΩ
2kΩ
NORMAL SWITCH MODE
POLE 1 USED AS A MICROPHONE INPUT
Functional Diagram/Typical Operating Circuits (continued)
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
14 ______________________________________________________________________________________
MAX9505
LOGIC
CONTROL
1V
75Ω
VIDOUT
CPGND C1P C1N CPVSSV
SS
C1
1µF
C2
1µF
100kΩ
BIAS
V
DD
C4
1µF
C3
1µF
CPV
DD
V
DD
GND
SGND
MODE1
VIDEO
DECODER
MODE0
1
2
3
4
VIDEO INPUT
AUDIO OUT LEFT
AUDIO OUT RIGHT
GROUND
4-POLE MULTIMEDIA JACK
S
IN
S
OUT
75Ω
LINEAR
REGULATOR
CHARGE PUMP
NORMAL SWITCH MODE
POLE 1 USED AS A VIDEO INPUT
Functional Diagram/Typical Operating Circuits (continued)
Chip Information
PROCESS: BICMOS
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
______________________________________________________________________________________ 15
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages
.)
QSOP.EPS
E
1
1
21-0055
PACKAGE OUTLINE, QSOP .150", .025" LEAD PITCH
MAX9505
DirectDrive Video Amplifier with
Reconstruction Filter and Analog Switch
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.
16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. Inc.
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages
.)
12x16L QFN THIN.EPS
0.10 C 0.08 C
0.10 M C A B
D
D/2
E/2
E
A1
A2
A
E2
E2/2
L
k
e
(ND - 1) X e
(NE - 1) X e
D2
D2/2
b
L
e
L
C
L
e
C
L
L
C
L
C
PACKAGE OUTLINE
21-0136
2
1
F
12, 16L THIN QFN, 3x3x0.8mm
MARKING
AAAA
1. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994.
EXPOSED PAD VARIATIONS
1.10T1633-1 0.95
CODES
PKG.
T1233-1
MIN.
0.95
NOM.
1.10
D2
1.251.100.951.25
NOM.
1.10
MAX.
1.25
MIN.
0.95
MAX.
1.25
E2
12
N
k
A2
0.25
NE
A1ND0
0.20 REF
-
-
3
0.0230.05
L
e
E
0.45
2.90
b
D
A
0.20
2.90
0.70
0.50 BSC.
0.55
3.00
0.65
3.10
0.25
3.00
0.75
0.30
3.10
0.80
16
0.20 REF
0.25
-
040.02
4
-
0.05
0.50 BSC.
0.30
2.90
0.40
3.00
0.20
2.90
0.70
0.25
3.00
0.75
3.10
0.50
0.80
3.10
0.30
PKG
REF. MIN.
12L 3x3
NOM. MAX. NOM.
16L 3x3
MIN. MAX.
0.35 x 45°
PIN ID
JEDEC
WEED-1
0.35 x 45° WEED-2
2. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES.
3. N IS THE TOTAL NUMBER OF TERMINALS.
4. 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.
5. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN 0.20 mm AND 0.25 mm
FROM TERMINAL TIP.
6. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY.
7. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION.
8. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS.
9. DRAWING CONFORMS TO JEDEC MO220 REVISION C.
NOTES:
T1233-3 1.10 1.25 0.95 1.10
0.35 x 45°1.25 WEED-10.95
T1633F-3 0.65
T1633-4
0.95
0.80
0.95
0.65
0.80
1.10
1.25
0.95
1.10
0.225 x 45°
0.95
WEED-2
0.35 x 45°
1.25
WEED-2
T1633-2 0.95
1.10
1.25
0.95
1.10
0.35 x 45°
1.25
WEED-2
NO
DOWN
BONDS
ALLOWED
YES
NO
YES
N/A
NO
PACKAGE OUTLINE
21-0136
2
2
F
12, 16L THIN QFN, 3x3x0.8
YESWEED-11.251.100.95 0.35 x 45°1.251.100.95T1233-4
T1633FH-3 0.65
0.80
0.95
0.225 x 45°0.65
0.80 0.95
WEED-2
N/A
10. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY
11. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY
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