19-4653; Rev 2; 12/10
KIT
ATION
EVALU
E
BL
AVAILA
Low-Power Audio/Video Switch with Audio
Volume Control for Dual SCART Connectors
General Description
The MAX9670/MAX9671 dual SCART matrices route
audio and video signals between a set-top box
decoder chip and two external SCART connectors
under I
2
C control. Operating from a 3.3V supply and a
12V supply, the MAX9670/MAX9671 consume 66mW
during quiescent operation and 300mW during average
operation when driving typical signals into typical
loads. Video input detection, video load detection, and
a 2.8mW standby mode facilitate the design of intelli-
gent, low-power set-top boxes.
The MAX9670/MAX9671 audio section contains a
buffered crosspoint to route audio inputs to audio out-
puts and programmable volume control from -62dB to
0dB in 2dB steps. The DirectDrive
®
output amplifiers
create a 2V
RMS
full-scale audio signal biased around
ground, eliminating the need for bulky output capaci-
tors and reducing click-and-pop noise. The zero-cross
detection circuitry also further reduces clicks and pops
by enabling audio sources to switch only during a zero-
crossing. The MAX9671 offers TV left and right audio
inputs.
The MAX9670/MAX9671 video section contains a
buffered crosspoint to route video inputs to video out-
puts. The standard-definition video signals from the set-
top box decoder chip are lowpass filtered to remove
out-of-band artifacts.
The MAX9670/MAX9671 also support slow-switching
and fast-switching signals. An interrupt signal from the
MAX9670/MAX9671 informs the microcontroller when
the system status has changed.
o
2.8mW Standby Mode Consumption
o
Programmable Audio Gain Control of -62dB to
0dB (TV Audio Outputs)
o
Clickless, Popless, DirectDrive Audio
o
Video Input and Video Load Detection
o
Video Reconstruction Filter with 10MHz Passband
and 52dB Attenuation at 27MHz
o
3.3V and 12V Supply Voltages
Features
o
66mW Quiescent Power Consumption
MAX9670/MAX9671
Ordering Information
PART
MAX9670CTL+
PIN-
TEMP RANGE
PACKAGE
0°C to +70°C
40 TQFN-EP*
TV R+L
AUDIO
INPUTS
No
Yes
MAX9671CTH+
0°C to +70°C 44 TQFN-EP*
+Denotes
a lead(Pb)-free/RoHS-compliant package.
*EP
= Exposed pad.
System Block Diagram
V
12
12V
V
VID
3.3V
V
AUD
3.3V
Applications
Set-Top Boxes
TVs
DVD Players
STB CHIP
I
2
C
µC
INTERRUPT
OUTPUT
MAX9670/MAX9671
RGB, Y/C, CVBS
I
2
C INTERFACE
REGISTERS AND
ACTIVITY
MONITOR
CVBS
L/R AUDIO
(MAX9671 ONLY)
L/R AUDIO
(MAX9670 ONLY)
SLOW SWITCHING
TV
SCART
VIDEO
ENCODER
RGB, Y/C, CVBS
VIDEO FILTERS AND
CROSSPOINT
FAST SWITCHING
STEREO
AUDIO
DAC
SINGLE-ENDED R/L
STEREO AUDIO
AUDIO CROSSPOINT
WITH DIRECTDRIVE
OUTPUTS, VOLUME
CONTROL
Y/C, CVBS
RGB, Y/C, CVBS
L/R AUDIO
SLOW SWITCHING
VCR
SCART
SLOW SWITCHING
FAST SWITCHING
FAST SWITCHING
Typical Application Circuit appears at end of data sheet.
CHARGE PUMP
DirectDrive is a registered trademark of Maxim Integrated
Products, Inc.
EP
GNDVID
________________________________________________________________
Maxim Integrated Products
1
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.
Low-Power Audio/Video Switch with Audio
Volume Control for Dual SCART Connectors
MAX9670/MAX9671
ABSOLUTE MAXIMUM RATINGS
V
VID
to GNDVID........................................................-0.3V to +4V
Audio Outputs to V
AUD
, EP .....................................Continuous
V
12
to EP.................................................................-0.3V to +14V
TV_SS, VCR_SS to V
12
, EP......................................Continuous
V
AUD
to EP ...............................................................-0.3V to +4V
Continuous Power Dissipation (T
A
= +70°C)
EP to GNDVID .......................................................-0.1V to +0.1V
40-Pin TQFN-EP (derate 26.3mW/°C above +70°C) ...2105.3mW
All Video Inputs, VCRIN_FS to GNDVID...................-0.3V to +4V
44-Pin TQFN-EP (derate 26.3mW/°C above +70°C)...2222.2mW
All Audio Inputs to EP .......................................-1V to (V
EP
+ 1V)
Junction-to-Case Thermal Resistance (θ
JC
) (Note 1)
SDA, SCL, DEV_ADDR,
INT
to GNDVID ..................-0.3V to +4V
40/44-pin TQFN-EP .........................................................1°C/W
TV_SS, VCR_SS to EP .................................-0.3V to (V
12
+ 0.3V)
Junction-to-Ambient Thermal Resistance (θ
JA
) (Note 1)
Current
40/44-pin TQFN-EP .......................................................27°C/W
All Video/Audio Inputs ...................................................±20mA
Operating Temperature Range...............................0°C to +70°C
C1P, C1N, CPVSS .........................................................±50mA
Junction Temperature ......................................................+150°C
Output Short-Circuit Current Duration
Storage Temperature Range .............................-65°C to +150°C
Video and Fast-Switching Outputs to V
VID
,
Lead Temperature (soldering, 10s) .................................+300°C
GNDVID.................................................................Continuous
Soldering Temperature (reflow) .......................................+260°C
Note 1:
Package thermal resistance were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to
www.maxim-ic.com/thermal-tutorial.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
12
= 12V, V
VID
= V
AUD
= 3.3V, V
GNDVID
= V
EP
= 0V, no load, T
A
= 0°C to +70°C, unless otherwise noted. Typical values are at
T
A
= +25°C.) (Note 2)
PARAMETER
Video Supply Voltage Range
Audio Supply Voltage Range
V
12
Supply Voltage Range
SYMBOL
V
VID
V
AUD
V
12
CONDITIONS
Inferred from video PSRR test at 3V and
3.6V
Inferred from audio PSRR test at 3V and
3.6V
Inferred from slow-switching levels
Normal operation; all video output
amplifiers are enabled and muted (Note 3)
V
VID
Quiescent Supply Current
I
VID_Q
Standby mode, slow switch inputs low
Shutdown
V
AUD
Quiescent Supply Current
I
AUD_Q
Normal operation (Note 3)
Shutdown
Normal operation
(Note 3)
Slow-switching output
set to low-level
Slow-switching output
set to medium-level
0.3
475
10
µA
3.2
MIN
3
3
11.4
TYP
3.3
3.3
12
16
MAX
3.6
3.6
12.6
30
1500
35
6
35
100
µA
UNITS
V
V
V
mA
µA
mA
µA
V
12
Quiescent Supply Current
I
12_Q
Shutdown, T
A
= +25°C
VIDEO CHARACTERISTICS
DC-COUPLED INPUT
R
L
= 75Ω to
GNDVID or 150Ω
to V
VID
/2; inferred
from gain test
V
VID
= 3V
V
VID
= 3.135V
V
VID
= 3.3V
1.3
1
300
1.15
Input Voltage Range
V
IN
1.15
V
P-P
Input Current
Input Resistance
I
IN
R
IN
V
IN
= 0.3V, T
A
= +25°C
2
µA
kΩ
2
_______________________________________________________________________________________
Low-Power Audio/Video Switch with Audio
Volume Control for Dual SCART Connectors
ELECTRICAL CHARACTERISTICS (continued)
(V
12
= 12V, V
VID
= V
AUD
= 3.3V, V
GNDVID
= V
EP
= 0V, no load, T
A
= 0°C to +70°C, unless otherwise noted. Typical values are at
T
A
= +25°C.) (Note 2)
PARAMETER
AC-COUPLED INPUT
Sync-Tip Clamp Level
Sync Crush
Input Clamping Current
Maximum Input Source
Resistance
Input Voltage
V
CLP
Sync-tip clamp
Sync-tip clamp; percentage reduction in
sync pulse (0.3V
P-P
); guaranteed by input
clamping current measurement, T
A
= +25°C
Sync-tip clamp, V
IN
= 0.3V, T
A
= +25°C
Input sync-tip circuit must be stable even if
the source resistance is as high as 300Ω
Bias circuit
High-impedance input circuit
Bias circuit
High-impedance input circuit
A
V
Guaranteed by output voltage swing
Guaranteed by output voltage swing of
TV_R/C_OUT, TV_G_OUT, and TV_B_OUT;
first input signal set is VCR_R/C_IN,
VCR_G_IN, and VCR_B_IN; second signal
set is ENC_R/C_IN, ENC_G_IN, and
ENC_B_IN
Sync-tip clamp (V
IN
= V
CLP
)
Bias circuit
Sync-tip clamp, measured at output,
V
VID
= 3V, V
IN
= V
CLP
to (V
CLP
+1.15V),
R
L
= 150Ω to V
VID
/2, R
L
= 75Ω to GNDVID
Measured at output, V
VID
= 3.135V, V
IN
=
V
CLP
to (V
CLP
+ 1.15V), R
L
= 150Ω to
V
VID
/2, R
L
= 75Ω to GNDVID
Output Voltage Swing
Bias circuit, measured at output, V
VID
= 3V,
V
IN
= (V
BIAS
- 0.575V) to (V
BIAS
+ 0.575V),
R
L
= 150Ω to V
VID
/2, R
L
= 75Ω to GNDVID
Measured at output, V
VID
= 3.135V,
V
IN
= (V
BIAS
- 0.575V) to (V
BIAS
+ 0.575V),
R
L
= 150Ω to V
VID
/2, R
L
= 75Ω to GNDVID
Output Short-Circuit Current
Output Resistance
Output Leakage Current
Power-Supply Rejection Ratio
R
OUT
Output disabled (load detection not active)
3V
≤
V
VID
≤
3.6V
35
2.3
1.95
0.57
0.3 x
V
VID
10
222
2
2.05
1
300
0.6
0.63
0.36 x
V
VID
V
-13
-4
+6
2
2
mV
%
µA
Ω
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX9670/MAX9671
Input Resistance
DC CHARACTERISTICS
DC Voltage Gain
kΩ
V/V
DC Gain Mismatch Among R, G,
and B Outputs
-2
+2
%
Output Level
0.1
1.3
0.30
1.5
2.3
0.51
1.78
V
2.243
2.3
2.358
V
P-P
2.243
2.3
100
0.5
2.358
mA
Ω
170
µA
dB
_______________________________________________________________________________________
3
Low-Power Audio/Video Switch with Audio
Volume Control for Dual SCART Connectors
MAX9670/MAX9671
ELECTRICAL CHARACTERISTICS (continued)
(V
12
= 12V, V
VID
= V
AUD
= 3.3V, V
GNDVID
= V
EP
= 0V, no load, T
A
= 0°C to +70°C, unless otherwise noted. Typical values are at
T
A
= +25°C.) (Note 2)
PARAMETER
AC CHARACTERISTICS
Filter Passband Flatness
Filter Attenuation
Slew Rate
Settling Time
Differential Gain
Differential Phase
2T Pulse-to-Bar K Rating
2T Pulse Response
2T Bar Response
Nonlinearity
Group Delay Distortion
Glitch Impulse Caused by
Charge-Pump Switching
Peak Signal to RMS Noise
Power-Supply Rejection Ratio
Output Impedance
Video Crosstalk
Reverse Isolation
DG
DP
V
OUT
= 2V
P-P
, f = 100kHz to 5.5MHz
V
OUT
= 2V
P-P
,
attenuation is
referred to 100kHz
f = 9.5MHz
f = 27MHz
f = 54MHz
-1
3
40
55
60
400
0.15
0.5
0.3
0.2
0.2
0.1
11
100
70
47
2
-80
92
V/µs
ns
%
Degrees
K%
K%
K%
%
ns
pV-s
dB
dB
Ω
dB
dB
dB
dB
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
OUT
= 2V
P-P
, no filter in video path
V
OUT
= 2V
P-P
, settle to 0.1% (Note 4)
5-step modulated staircase, f = 4.43MHz
5-step modulated staircase, f = 4.43MHz
2T = 200ns, bar time is 18µs, the beginning
2.5% and the ending 2.5% of the bar time is
ignored
2T = 200ns
2T = 200ns, bar time is 18µs, the beginning
2.5% and the ending 2.5% of the bar time is
ignored
5-step staircase
100kHz
≤
f
≤
5MHz, outputs are 2V
P-P
Measured at outputs
100kHz
≤
f
≤
5MHz
f = 100kHz, 100mV
P-P
f = 5MHz
f = 4.43MHz
VCR SCART inputs to encoder inputs,
full-power mode with VCR being looped
through to TV, f = 4.43MHz
Enable VCR_R/C_OUT pulldown through
I
2
C interface
V
IN
= -0.707V to +0.707V
V
IN
= -0.707V to +0.707V
f = 20Hz to 20kHz, 0.25V
RMS
input
0.25V
RMS
input, frequency where output is
-3dB referenced to 1kHz
No sustained oscillations; 75Ω series
resistor on output
3.95
-1.5
Pulldown Resistance
AUDIO CHARACTERISTICS
Voltage Gain
Gain Mismatch
Flatness
Frequency Bandwidth
Capacitive Drive
4.4
7.5
Ω
4
0.006
230
300
4.05
+1.5
V/V
%
dB
kHz
pF
4
_______________________________________________________________________________________
Low-Power Audio/Video Switch with Audio
Volume Control for Dual SCART Connectors
ELECTRICAL CHARACTERISTICS (continued)
(V
12
= 12V, V
VID
= V
AUD
= 3.3V, V
GNDVID
= V
EP
= 0V, no load, T
A
= 0°C to +70°C, unless otherwise noted. Typical values are at
T
A
= +25°C.) (Note 2)
PARAMETER
Input Resistance
Input Bias Current
Input Signal Amplitude
Output DC Level
Power-Supply Rejection Ratio
Signal-to-Noise Ratio
Total Harmonic Distortion Plus
Noise
Output Impedance
Volume Control Attenuation Step
Volume Control Minimum
Attenuation
Volume Control Maximum
Attenuation
Mute Suppression
Audio Crosstalk
VIDEO-TO-AUDIO INTERACTION
Crosstalk
CHARGE PUMP
Switching Frequency
FAST SWITCHING
Input Low
Input High Level
Input Current
Output Low Voltage
Output High Voltage
Output Resistance
Rise Time
Fall Time
SLOW SWITCHING
Input Low Voltage
Input Medium Voltage
Input High Voltage
4.5
9.5
2
7
V
V
V
143Ω to GNDVID
143Ω to GNDVID
T
A
= +25°C
I
OL
= 0.5mA
I
OH
= 0.5mA
V
VID
-
0.1
7
12
10
1
10
0.1
0.4
V
V
µA
V
V
Ω
ns
ns
570
kHz
Video input: f = 15kHz, 1V
P-P
signal
Audio input: f = 15kHz, 0.5V
RMS
signal
92
dB
f = 1kHz, 0.25V
RMS
input
f = 1kHz, 0.25V
RMS
input
SYMBOL
CONDITIONS
V
IN
= -0.707V to +0.707V
V
IN
= 0, T
A
= +25°C
f = 1kHz, THD < 1%
No input signal, V
IN
grounded
DC
f = 1kHz
f = 1kHz, 0.25V
RMS
input, 20Hz to 20kHz
R
L
= 3.33kΩ, f = 1kHz, 0.25V
RMS
input
R
L
= 3.33kΩ, f = 1kHz, 0.5V
RMS
input
f = 1kHz
Programmable gain to TV SCART volume
control from -62dB to 0
-4
75
100
90
96
0.002
0.001
0.4
2
0
62
110
100
0.5
+4
MIN
TYP
10
500
MAX
UNITS
MΩ
nA
V
RMS
mV
dB
dB
%
Ω
dB
dB
dB
dB
dB
MAX9670/MAX9671
_______________________________________________________________________________________
5
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