MAXIM MAX4079 Technical data

General Description

The MAX4079 filters and buffers video (NTSC/PAL/DVB)
and stereo audio signals from the MPEG decoder of a
cable/satellite receiver, VCR/DVD player, or a TV to an
external load. The MAX4079 has luma-chroma (Y-C)
and composite (CVBS) video inputs with one Y-C and
two CVBS outputs. All video inputs are AC-coupled with
internal DC biasing on the chroma input and active
clamps for the luma and composite.

The MAX4079 video reconstruction filters have a 6MHz
cutoff frequency and 50dB attenuation at 27MHz. The
filters are matched with flat group delay for standard­definition video. The video gain is fixed at +6dB to drive
a 75Ω back-terminated load (150Ω) to unity gain. The
video outputs can be either DC- or AC-coupled and are
powered by a single +5V supply.

The MAX4079 audio amplifiers have differential inputs
for optimum performance, but can be used with single­ended sources with external biasing. The audio chan­nels have a fixed gain of +6dB and deliver 2.6V

RMS

output with a differential input of ±1.85V. The audio
amplifiers operate from a +9V to +12V single supply
and feature an internal bias generator. An on-chip
mixer also provides a mono output, with +3dB gain,
derived from the left and right audio channels.

The MAX4079 is available in 24-pin TSSOP package,
and is fully specified over the 0°C to +70°C commercial
temperature range. The MAX4079 Evaluation Kit is
available to help speed designs.

Applications

Satellite Receivers

Cable Receivers

Home Theater Systems

DVD Players

AV Receivers

Televisions

Features

♦ Integrated Video Reconstruction Filters—6MHz

Lowpass Filter Supports NTSC, PAL, or DVB per
ITU-601

♦ Integrated Video and Audio Amplifiers

♦ Integrated Video Input Clamps and Biasing

♦ Mono Audio and CVBS Output to Drive External

Modulator

♦ +5V (Video) and +9V to +12V (Audio) Single-

Supply Operation

♦ Differential/Single-Ended Audio Inputs

♦ 24-Pin TSSOP Package

MAX4079

Complete Audio/Video

Backend Solution

________________________________________________________________

Maxim Integrated Products

1

Ordering Information

19-3780; Rev 1; 3/09

EVALUATION KIT

AVAILABLE

+

Denotes lead(Pb)-free package.

Functional Diagram

LP

FILTER

CLAMP

BIAS

NETWORK

CLAMP

RINP

RINN

LINP

LINN

CIN

CVBSIN

YIN

COUT

CVBSOUT1

CVBSOUT2

ROUT1

ROUT2

MONO

LOUT1

LOUT2

GVID

GAUD

VVID

AUDV

REXT

CBYPASS

+3dB

+6dB

+6dB

+6dB

+6dB

+6dB

+6dB

+6dB

+6dB

YOUT

LP

FILTER

LP

FILTER

MAX4079

Pin Configuration appears at end of data sheet.

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.

PART TEMP RANGE PIN-PACKAGE

MAX4079CUG+ 0°C to +70°C 24 TSSOP

MAX4079

Complete Audio/Video
Backend Solution

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

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.

GVID to GAUD.......................................................-0.1V to +0.1V

VVID to GVID ............................................................-0.3V to +6V

AUDV to GAUD ......................................................-0.3V to +14V

LINP, LINN, RINP, RINN, CBYPASS to GAUD .........-0.3V to +6V

LOUT1, LOUT2, ROUT1, ROUT2,

MONO to GAUD ......-0.3V to lower of (+9V and AUDV + 0.3V)

YIN, CIN, CVBSIN, REXT to GVID.............-0.3V to (VVID + 0.3V)

YOUT, COUT, CVBSOUT1, CVBSOUT2 to

GVID.......................................................-0.3V to (VVID + 0.3V)

Video Output Short-Circuit Duration to GVID or

VVID ........................................................................Continuous

Audio Output Short-Circuit Duration to GAUD or

AUDV.......................................................................Continuous

Continuous Power Dissipation (T

A

= +70°C)

24-Pin TSSOP (derate 12.2mW/°C above +70°C) .....975.6mW

Operating Temperature Range...............................0°C to +70°C

Storage Temperature Range .............................-65°C to +150°C

Junction Temperature......................................................+150°C

Lead Temperature (soldering, 10s) .................................+300°C

DC ELECTRICAL CHARACTERISTICS

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

LOAD_VID

= 150Ω to GVID, R

REXT

= 10kΩ ±1%, C

CBYPASS

= 1µF, TA= 0°C to

+70°C, unless otherwise noted. Typical values are at T

A

= +25°C.) (Note 1)

SUPPLIES

Audio Supply Voltage Range AUDV 8.5 12.6 V

Video Supply Voltage Range VVID 4.75 5.0 5.25 V

Video Quiescent Supply Current I

Audio Quiescent Supply Current I

Thermal Shutdown T

Thermal-Shutdown Hysteresis T

VIDEO

Voltage Gain A

Gain Matching ΔA

Input Voltage Swing V

Clamp Voltage V

Chroma Bias V

Droop D (Note 2) 2 %

REXT Reference Voltage V

Input Resistance R

Input Clamping Current I

Output Voltage Swing V

Short-Circuit Current I

Power-Supply Rejection Ratio PSRR

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

CCV

CCA

SD,HYS

V,VID

V,VIDVIN

IN,VID

CLMP

BIAS

REXT

IN,VID

CLMP

OUT,VID

SC,VID

SD

V

= 5.25V, no load, all video inputs

VVID

AC-coupled to ground

V

= 12.6V, no load, audio inputs

AUDV

biased at 2.5V

Rising die temperature +150 °C

VIN = 1V

YIN, CVBSIN 0 1.2

CIN 0 0.9

CVBSOUT_ and YOUT, no signal, no load 1.0 V

COUT, no signal, no load 2.1 V

CVBSIN or YIN 2.3 MΩ

CIN 10 kΩ

CVBSIN or YIN input, VIN = 3.5V 1 2.5 4 µA

CVBSOUT_, YOUT 2.4

COUT 1.8

Video output shorted to VVID or GVID 50 mA

4.75V ≤ V

VID

5.25V

= 1V

P-P

P-P

VVID

, all video inputs, no load 5.8 6 6.2 dB

, all video inputs, no load -0.4 +0.4 dB

YOUT/COUT 48

≤

CVBSOUT_ 48

0.85 1.00 1.15 V

60 100 mA

815mA

25 °C

V

P-P

V

P-P

dB

MAX4079

Complete Audio/Video

Backend Solution

_______________________________________________________________________________________ 3

DC ELECTRICAL CHARACTERISTICS (continued)

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

LOAD_VID

= 150Ω to GVID, R

REXT

= 10kΩ ±1%, C

CBYPASS

= 1µF, TA= 0°C to

+70°C, unless otherwise noted. Typical values are at T

A

= +25°C.) (Note 1)

AC ELECTRICAL CHARACTERISTICS

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

IN_VIDEO

= 75Ω to GVID, C

IN_VIDEO

= 0.1µF, R

LOAD_VID

= 150Ω to GVID,

C

OUT_AUDIO

= 10µF, R

LOAD_AUD

= 10kΩ ±1% to GAUD, R

REXT

= 10kΩ, C

CBYPASS

= 1µF, TA= 0°C to +70°C, unless otherwise

noted. Typical values are at T

A

= +25°C.) (Note 1)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

AUDIO

Voltage Gain A

Mono Voltage Gain A

Gain Matching Between
Channels

Input Voltage Range V

Differential Input Voltage Range V

Input Current I

Output Voltage Swing V

Short-Circuit Current I

V,AUD

V,MONO

ΔA

V,AUD

IN,AUD

IN,AUD DIF

IN,AUD

OUT,AUD

SC,AUD

Power-Supply Rejection Ratio PSRR

Common-Mode Rejection Ratio CMRR

1.414V

1.414V

1.414V

differential input 5.8 6 6.2 dB

P-P

differential input, LIN = R

P-P

differential input -0.4 +0.4 dB

P-P

Inferred from CMRR test 0.3 5.2 V

Inferred from output voltage swing -1.85 +1.85 V

Input overdriven, 10kΩ load to 4.15V 7.4 V

8.5V ≤ V

AUD

0.3V ≤ VCM ≤ 5.2V 50 60 dB

AUD

≤ 12.6V 70 dB

AUDV

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

VIDEO

Filter Attenuation A

Slew Rate SR V

Differential Gain DG

Differential Phase DP

Power-Supply Rejection Ratio PSRR

Peak Signal to RMS Noise SNR

Group Delay Deviation GD

Output Impedance Z

Capacitive Load C

Video Crosstalk X

Audio/Video Crosstalk X

CVBSOUT1 = CVBSOUT2 =
YOUT = COUT = 2V

VIDEO

R
attenuation is referred to
100kHz

CVBSOUT_, YOUT, COUT, 5-step
modulated staircase

CVBSOUT_, YOUT, COUT, 5-step
modulated staircase

f = 100kHz, 0.5V

VID

VID

CVBSOUT_, YOUT, COUT, VIN = 1V

CVBSOUT_, YOUT, COUT, f

4.5MHz

OUT,VID

L,VID

TALK,VID

TALK,VD/AD

f = 3.58MHz 0.5 Ω

No sustained oscillations 35 pF

f = 3.58MHz, 1V
active inputs

f = 15kHz, 1V
active audio or video inputs

= 150Ω to ground,

L

= 2V

OUT

P-P

P-P

P-P

P-P

P-P

input, between any two

input, between any two

IN

;

f = 4MHz -0.5 +0.5

2.8 3 3.2 dB

f = 7MHz 3

f = 27MHz 40 50

YOUT/COUT 48

CVBSOUT_ 44

P-P

= 0.1MHz to

IN

2µA

15 mA

30 V/µs

0.5 %

0.9 degrees

65 dB

25 ns

-63

-76

P-P

dB

dB

dB

MAX4079

Complete Audio/Video
Backend Solution

4 _______________________________________________________________________________________

AC ELECTRICAL CHARACTERISTICS (continued)

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

IN_VIDEO

= 75Ω to GVID, C

IN_VIDEO

= 0.1µF, R

LOAD_VID

= 150Ω to GVID,

C

OUT_AUDIO

= 10µF, R

LOAD_AUD

= 10kΩ ±1% to GAUD, R

REXT

= 10kΩ, C

CBYPASS

= 1µF, TA= 0°C to +70°C, unless otherwise

noted. Typical values are at T

A

= +25°C.) (Note 1)

Note 1: All devices are 100% production tested at TA= +25°C. Specifications over temperature limits are guaranteed by design.
Note 2: Droop is defined as the percentage change in the DC level from the start to the end of a video line. Inferred from input

clamping current with a 0.1µF coupling capacitor.

CHROMA LARGE-SIGNAL BANDWIDTH

MAX4079 toc01

FREQUENCY (MHz)

RESPONSE (dB)

101

-70

-60

-50

-40

-30

-20

-10

0

10

-80

0.1 100

VIN = 1V

P-P

LUMA LARGE-SIGNAL BANDWIDTH

MAX4079 toc02

FREQUENCY (MHz)

RESPONSE (dB)

101

-70

-60

-50

-40

-30

-20

-10

0

10

-80

0.1 100

VIN = 1V

P-P

CVBSOUT_ LARGE-SIGNAL BANDWIDTH

MAX4079 toc03

FREQUENCY (MHz)

RESPONSE (dB)

101

-70

-60

-50

-40

-30

-20

-10

0

10

-80

0.1 100

VIN = 1V

P-P

Typical Operating Characteristics

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

IN_VIDEO

= 75Ω to GVID, C

IN_VIDEO

= 0.1µF, R

LOAD_VID

= 150Ω to GVID

,

C

OUT_AUDIO

= 10µF, R

LOAD_AUD

= 10kΩ to G

AUD

, R

REXT

= 10kΩ, C

BYPASS

= 1µF, TA= +25°C, unless otherwise noted.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

AUDIO

Gain Flatness ΔA

Signal-to-Noise Ratio SNR

Total Harmonic Distortion
Plus Noise

Output Impedance Z

Power-Supply Rejection Ratio PSRR

Crosstalk X

Capacitive Load C

LOUT_, ROUT_, fIN = 20Hz to 20kHz,

AUD

0.5V

MONO, fIN = 20Hz to 20kHz, 0.5V
input

fIN = 1.0kHz, 0.5V

AUD

highpass filter at 20Hz, lowpass filter at
20kHz

THD+N

O,AUD

AUD,AC

TLK,AUD

L,AUD

fIN = 1.0kHz, 0.5V

f

f = 1kHz 0.2 Ω

f = 1kHz, V

f = 1kHz, 0.5V

No sustained oscillations 200 pF

input

RMS

= 1.0kHz, 1V

IN

RIPPLE

0.01

, CCIR weighing

RMS

RMS

0.01

85 dB

RMS

RMS

= 200mV

input 70 dB

RMS

P-P

0.005

0.003

60 dB

dB

%

MAX4079

Complete Audio/Video

Backend Solution

_______________________________________________________________________________________

5

Typical Operating Characteristics (continued)

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

IN_VIDEO

= 75Ω to GVID, C

IN_VIDEO

= 0.1µF, R

LOAD_VID

= 150Ω to GVID

,

C

OUT_AUDIO

= 10µF, R

LOAD_AUD

= 10kΩ to G

AUD

, R

REXT

= 10kΩ, C

BYPASS

= 1µF, TA= +25°C, unless otherwise noted.)

VIDEO CROSSTALK (CVBSOUT_ TO YIN)

-40
VIN = 1V

-50

-60

-70

-80

RESPONSE (dB)

-90

-100

-110

-120

0.1 100

P-P

FREQUENCY (MHz)

VIDEO CROSSTALK (COUT TO YIN)

-40
VIN = 1V

-50

-60

-70

-80

RESPONSE (dB)

-90

-100

-110

-120

0.1 100

P-P

FREQUENCY (MHz)

101

101

MAX4079 toc04

MAX4079 toc07

VIDEO CROSSTALK (CVBSOUT_ TO CIN)

-40
VIN = 1V

-50

-60

-70

-80

RESPONSE (dB)

-90

-100

-110

-120

0.1 100

VIDEO CROSSTALK (YOUT TO CVBSIN)

-40
VIN = 1V

-50

-60

-70

-80

RESPONSE (dB)

-90

-100

-110

-120

0.1 100

P-P

FREQUENCY (MHz)

P-P

FREQUENCY (MHz)

VIDEO CROSSTALK (COUT TO CVBSIN)

-40
VIN = 1V

-50

MAX4079 toc05

-60

-70

-80

RESPONSE (dB)

-90

-100

-110

-120

101

0.1 100

P-P

FREQUENCY (MHz)

VIDEO CROSSTALK (YOUT TO CIN)

-40
VIN = 1V

-50

MAX4079 toc08

-60

-70

-80

RESPONSE (dB)

-90

-100

-110

-120

101

0.1 100

P-P

FREQUENCY (MHz)

MAX4079 toc06

101

MAX4079 toc09

101

100

90

80

70

60

50

DELAY (ns)

40

30

20

10

0

0.1 10

1

FREQUENCY (MHz)

CVBSOUT_ GROUP DELAY

MAX4079 toc10

100

CHROMA GROUP DELAY

90

80

70

60

50

DELAY (ns)

40

30

20

10

0

0.1 10

1

FREQUENCY (MHz)

MAX4079 toc11

100

YOUT GROUP DELAY

90

80

70

60

50

DELAY (ns)

40

30

20

10

0

0.1 10

1

FREQUENCY (MHz)

MAX4079 toc12

MAX4079

Complete Audio/Video
Backend Solution

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

IN_VIDEO

= 75Ω to GVID, C

IN_VIDEO

= 0.1µF, R

LOAD_VID

= 150Ω to GVID

,

C

OUT_AUDIO

= 10µF, R

LOAD_AUD

= 10kΩ to G

AUD

, R

REXT

= 10kΩ, C

BYPASS

= 1µF, TA= +25°C, unless otherwise noted.)

DIFFERENTIAL GAIN

MAX4079 toc13

DIFFERENTIAL PHASE (deg)

1324567

1324567

0.2

0.1

0

-0.1

-0.2

DIFFERENTIAL GAIN (%)

0.2

0.1

0

-0.1

-0.2

DIFFERENTIAL PHASE

AUDIO LARGE-SIGNAL BANDWIDTH

MAX4079 toc14

FREQUENCY (kHz)

RESPONSE (dB)

1010.1

2.8

2.9

3.0

3.1

3.2

3.3

2.7

0.01 100

MONO CHANNEL

VIN = 0.5V

RMS

AUDIO LARGE-SIGNAL BANDWIDTH

MAX4079 toc15

FREQUENCY (kHz)

RESPONSE (dB)

1010.1

5.5

6.0

6.5

7.0

5.0

0.01 100

RIGHT CHANNEL

VIN = 0.5V

RMS

AUDIO LARGE-SIGNAL BANDWIDTH

MAX4079 toc16

FREQUENCY (kHz)

RESPONSE (dB)

1010.1

5.5

6.0

6.5

7.0

5.0

0.01 100

LEFT CHANNEL

VIN = 0.5V

RMS

AUDIO CROSSTALK

MAX4079 toc17

FREQUENCY (kHz)

RESPONSE (dB)

1010.1

-110

-100

-90

-80

-70

-60

-50

-40

-120

0.01 100

LEFT TO RIGHT CHANNEL

RIGHT TO LEFT CHANNEL

VIN = 0.5V

RMS

TOTAL HARMONIC DISTORTION

PLUS NOISE RATIO (LEFT CHANNEL)

MAX4079 toc18

FREQUENCY (kHz)

THD+N (%)

1010.1

0.002

0.003

0.004

0.005

0.006

0.007

0.008

0.009

0.010

0.001

0.01 100

VIN = 1V

RMS

VIN = 0.5V

RMS

Typical Operating Characteristics (continued)

(V

VVID

= +5V, V

AUDV

= +12V, V

GVID

= V

GAUD

= 0V, R

IN_VIDEO

= 75Ω to GVID, C

IN_VIDEO

= 0.1µF, R

LOAD_VID

= 150Ω to GVID

,

C

OUT_AUDIO

= 10µF, R

LOAD_AUD

= 10kΩ to G

AUD

, R

REXT

= 10kΩ, C

BYPASS

= 1µF, TA= +25°C, unless otherwise noted.)

MAX4079

Complete Audio/Video

Backend Solution

_______________________________________________________________________________________

7

TOTAL HARMONIC DISTORTION

PLUS NOISE RATIO (RIGHT CHANNEL)

0.010

0.009

0.008

0.007

VIN = 0.5V

0.006

0.005

THD+N (%)

0.004

0.003

0.002

0.001

0.01 100

VIN = 1V

RMS

RMS

FREQUENCY (kHz)

3.5
VIN = 3.5V

3.2

2.9

2.6

INPUT CLAMP CURRENT (μA)

2.3

1010.1

MAX4079 toc19

VIDEO SUPPLY CURRENT (mA)

INPUT CLAMP CURRENT

vs. TEMPERATURE

CVBSIN

YIN

65

64

63

62

61

60

59

58

57

56

55

0 10203040506070

MAX4079 toc22

VIDEO SUPPLY CURRENT

vs. TEMPERATURE

TEMPERATURE (°C)

10,000

1000

INPUT CLAMP CURRENT (μA)

100

10

9.0

8.5

MAX4079 toc20

8.0

7.5

7.0

6.5

6.0

AUDIO SUPPLY CURRENT (mA)

5.5

5.0
02010 30 40 50 60 70

INPUT CLAMP CURRENT

vs. INPUT VOLTAGE

SOURCING

AUDIO SUPPLY CURRENT

vs. TEMPERATURE

TEMPERATURE (°C)

SINKING

YIN

CVBSIN

MAX4079 toc23

MAX4079 toc21

2.0
0 10203040506070

TEMPERATURE (°C)

OUTPUT BIAS VOLTAGE

vs. TEMPERATURE

1.3

1.2

1.1

1.0

0.9

OUTPUT BIAS VOLTAGE (V)

0.8

0.7
02010 30 40 50 60 70

YOUT

CVBSOUT_

TEMPERATURE (°C)

MAX4079 toc24

1

0 5.0

INPUT VOLTAGE (V)

OUTPUT BIAS VOLTAGE

vs. TEMPERATURE

2.5

2.3

2.1

1.9

OUTPUT BIAS VOLTAGE (V)

1.7

1.5
02010 30 40 50 60 70

COUT

TEMPERATURE (°C)

4.54.03.53.02.52.01.51.00.5

MAX4079 toc25

MAX4079

Detailed Description

The MAX4079 filters and buffers video (NTSC/PAL/DVB)
and stereo audio signals from the MPEG decoder of a
cable/satellite receiver, VCR/DVD player, or a TV to an
external load. The MAX4079 has luma-chroma (Y-C)
and composite (CVBS) video inputs with one Y-C and
two CVBS outputs. All video inputs are AC-coupled with
internal DC biasing on the chroma input and active
clamps for the luma and composite.

The MAX4079 video reconstruction filters have a 6MHz
cutoff frequency and 50dB attenuation at 27MHz. The
filters are matched, with flat group delay for standard­definition video. The video gain is fixed at +6dB to drive
a 75Ω back-terminated load (150Ω) to unity gain. The
video outputs can be either DC- or AC-coupled and are
powered by a single +5V supply.

The MAX4079 audio amplifiers have differential inputs
for optimum performance, but can be used with single­ended sources with external biasing. The audio chan­nels have a fixed gain of +6dB and deliver 2.6V

RMS

output with a differential input of ±1.85V. The audio

amplifiers operate from a +9V to +12V single supply
and feature an internal bias generator. An on-chip
mixer also provides a mono output, with +3dB gain,
derived from the left and right audio channels.

Video

The video section of the MAX4079 implements DC
restore/biasing, amplification, and reconstruction filter­ing for the Y-C and CVBS input signals. All of the video
inputs are AC-coupled. DC restore is performed using
a sync tip clamp for both luma and composite video
channels. The chroma DC level input is biased at the
midlevel of the signal.

All video channels have a fixed gain of +6dB. The DC
level at the video outputs is controlled so that coupling
capacitors are not required.

All composite and luma video outputs are capable of
driving 2.4V

P-P

, and the chroma output is capable of

driving 1.8V

P-P

into 150Ω resistive load to ground. Up
to 35pF of load capacitance can be tolerated at each
video output without stability or slew-rate issues.

Complete Audio/Video
Backend Solution

8 _______________________________________________________________________________________

Pin Description

PIN NAME FUNCTION

1 REXT External Filter Resistor. Bypass with a 10kΩ ±1% resistor and a 0.1µF capacitor to GVID.

2, 24 VVID Video Power-Supply Input

3 CVBSIN Composite Video Input

4, 21 GVID Video Ground

5 YIN Luma Input

6 CBYPASS Audio LDO Regulator Bypass Capacitor. Bypass with a1µF capacitor to GAUD.

7 CIN Chroma Input

8 AUDV Audio Power-Supply Input

9 LINP Left-Channel Audio Positive Input

10 LINN Left-Channel Audio Negative Input

11 RINN Right-Channel Audio Negative Input

12 RINP Right-Channel Audio Positive Input

13 ROUT2 Right-Channel Audio Output 2

14 ROUT1 Right-Channel Audio Output 1

15 GAUD Audio Ground

16 MONO Mono Audio Output

17 LOUT2 Left-Channel Audio Output 2

18 LOUT1 Left-Channel Audio Output 1

19 COUT Chroma Video Output

20 YOUT Luma Video Output

22 CVBSOUT1 Composite Video Output 1

23 CVBSOUT2 Composite Video Output 2

All video inputs are stable with up to 150Ω source resis­tance. For higher values, consult Maxim applications.

Video Reconstruction Filter

The MAX4079 reconstruction filters are 4th-order
Butterworth filters that provide a cutoff frequency of
6MHz and flat group delay response up to 4.5MHz. The
stopband offers 26dB of attenuation at 13.5MHz and
50dB at 27MHz.

Audio

The audio section of the MAX4079 is a stereo amplifier
with one differential input and two single-ended outputs
for each channel (left and right). A mono output is pro­vided by summing the two channels of the stereo signal
together. The stereo channels have a +6dB typical
gain, while the mono has a +3dB gain.

The audio inputs can be DC-coupled, eliminating space­consuming coupling capacitors. Each of the five outputs
can deliver 2.6V

RMS

into an AC-coupled 10kΩ load.

Applications Information

Audio DAC Interfacing

Differential Audio DAC

The MAX4079 accepts differential audio signals. Figure
1 shows a typical configuration for connecting the
device to an audio DAC with differential outputs. Figure
2 shows the reconstruction filters that can be used for
the differential audio inputs. Carefully select resistors
and capacitors to attenuate out-of-band noise and mini-

mize the effect on the gain. The common-mode voltage
for these signals is typically 2.5V.

Single-Ended Audio DAC

The MAX4079 can also be configured for single-ended
inputs. Figure 3 shows how to connect an audio DAC with
single-ended outputs to the MAX4079. Figure 4 shows
how reconstruction filters can be used for single-ended
audio inputs. Choose these values to minimize the
effect on gain.

If the single-ended audio DAC does not include a com­mon-mode voltage output, create a bias point with well­matched resistors and couple the audio signal to the
positive differential input (see Figure 5). The bias point
can also be created using a resistor-divider network
from the video supply voltage. Note that the tolerance of
the resistors will affect the common-mode and power­supply rejection ratios. Tighter tolerances improve the per­formance of CMRR and PSRR, e.g., 1% resistors will not
give any better than 40dB of CMRR and PSRR, whereas

0.1% resistors could improve the number to 60dB.

Power Supplies and Bypassing

The MAX4079 features single +5V (video) and +12V
(audio) supply operation, and requires no negative
supply. Connect the VVID pins together and bypass to
GVID with 0.01µF, 0.1µF, and 4.7µF capacitors in paral­lel. Bypass the AUDV to GAUD with 0.1µF, 1µF, and
47µF capacitors in parallel. Bypass CBYPASS to GAUD
with a 1µF capacitor (see the

Typical Operating Circuit

).

MAX4079

Complete Audio/Video

Backend Solution

_______________________________________________________________________________________ 9

Figure 1. Differential Audio Inputs

Figure 2. Filtering Differential Audio Inputs

+5V

A

OUTL+

A

OUTL-

AUDIO

DAC

A

OUTR+

A

OUTR-

LINP

LINN

RINP

RINN

LEFT AUDIO
CHANNEL

RIGHT AUDIO
CHANNEL

MAX4079

A

OUTL+

A

OUTL-

R1

C1

R1

R2

R2

LINP

LINN

C2

C2

MAX4079

MAX4079

Complete Audio/Video
Backend Solution

10 ______________________________________________________________________________________

Figure 3. Single-Ended Audio Inputs

Figure 4. Filtering Single-Ended Audio Inputs

Figure 5. Biasing Single-Ended Audio Inputs

Figure 6. Vertical Sync Interval

Layout and Grounding

For optimal performance, stitch ground vias between the
narrow adjacent signal traces to minimize crosstalk.
Avoid running video traces parallel to high-speed data
lines. The MAX4079 provides separate ground connections

for video and audio supplies. For best performance use
separate ground planes for each of the ground returns,
and connect all ground planes together at a single point.
Refer to the MAX4079 Evaluation Kit for a proven circuit
board layout example.

+5V

LINP

LINN

~2.5V

RINP

RINN

AUDIO

DAC

A

A

OUTL

V

CM

OUTR

V

BIAS

LEFT AUDIO
CHANNEL

RIGHT AUDIO
CHANNEL

MAX4079

A

OUTL

V

CM

R1

C1

R1

LINP

LINN

MAX4079

R

A

OUTL

R

R

A

OUTR

R

R

LINP

LINN

R

V

BIAS

R

RINP

RINN

R

LEFT AUDIO
CHANNEL

MAX4079

RIGHT AUDIO
CHANNEL

INPUT

OUTPUT

40μs/div

MAX4079

Complete Audio/Video

Backend Solution

______________________________________________________________________________________ 11

Typical Operating Circuit

+5V VIDEO SUPPLY

4.7μF

YIN

0.1μF

RINN

LINN

0.1μF

RINP

LINP

0.01μF

75Ω

75Ω

75Ω

10kΩ

0.1μF

0.1μF

0.1μF

VVID

VVID

GVID

GVID

YIN

CINCIN

CVBSINCVBSIN

RINP

RINN

LINP

LINN

REXT

MAX4079

AUDV

GAUD

YOUT

COUT

CVBSOUT1

CVBSOUT2

ROUT1

ROUT2

MONO

LOUT1

LOUT2

CBYPASS

10μF

+12V AUDIO SUPPLY

0.1μF

75Ω

75Ω

75Ω

75Ω

10μF

10kΩ

10μF

10kΩ

330μF

47μF

*OPTIONAL CAPACITORS
(TYPICAL VALUES SHOWN)

Z

Z

Z

Z

10kΩ

10μF

10kΩ

= 75Ω

0

= 75Ω

0

= 75Ω

0

= 75Ω

0

10kΩ

75Ω

75Ω

1μF

330μF

330μF

330μF

10μF

75Ω

75Ω

1μF

MAX4079

Complete Audio/Video
Backend Solution

12 ______________________________________________________________________________________

Pin Configuration

Chip Information

PROCESS: BiCMOS

TOP VIEW

REXT

VVID

CVBSIN

YIN

CBYPASS

CIN

LINP

LINN

RINN

+

1

2

3

4

MAX4079

5

6

7

8

9

10

11

12

TSSOP

24

23

22

21

20

19

18

17

16

15

14

13

VVID

CVBSOUT2

CVBSOUT1

GVIDGVID

YOUT

COUT

LOUT1

LOUT2AUDV

MONO

GAUD

ROUT1

ROUT2RINP

MAX4079

Complete Audio/Video

Backend Solution

______________________________________________________________________________________ 13

MAX4079

PACKAGE TYPE PACKAGE CODE DOCUMENT NO.

24 TSSOP U24+1

21-0066

Package Information

For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.

TSSOP4.40mm.EPS

MAX4079

Complete Audio/Video
Backend Solution

14 ______________________________________________________________________________________

Package Information (continued)

For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.

N

1

TOP VIEW

e

FRONT VIEW

MAX

0.104

0.012

0.019

0.013

0.299

0.050

MAX

0.5120.496D

MILLIMETERS

MAX

MIN

2.65

2.35

0.30

0.10

0.49

0.35

0.23

0.32

7.40 7.60

0.40 1.27

MILLIMETERS

MAX

MIN

12.60 13.00

SOICW.EPS

N MS013

20 AC

INCHES

MIN

DIM

0.093A

0.004

A1

0.014

B

0.009

C

H

E

D

A

B

A1

C

L

e 0.050 1.27

0.291

E
H 0.4190.394 10.00 10.65

0.016L

VARIATIONS:

INCHES

MINDIM

0.398 0.413 AA10.5010.10 16

D

0.447 0.463 AB11.7511.35 18

D

D 0.6140.598 15.20 2415.60 AD
D 0.7130.697 17.70 2818.10 AE

0∞-8∞

SIDE VIEW

PROPRIETARY INFORMATION

TITLE:

PACKAGE OUTLINE, .300" SOIC

21-0042

REV.DOCUMENT CONTROL NO.APPROVAL

1

B

1

MAX4079

Complete Audio/Video

Backend Solution

Heaney

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.

Revision History

REVISION

NUMBER

0 8/05 Initial release —

1 3/09 Changes to remove SO package, style edits 1–7, 12, 13, 14

REVISION

DATE

DESCRIPTION

CHANGED

PAGES