MAXIM MAX7432A Technical data

General Description

The MAX7428/MAX7430/MAX7432A filters are low-cost,
high-performance replacements for standard discrete fil­ter and buffer solutions. The MAX7428/MAX7430/
MAX7432A are ideal for anti-aliasing and DAC smooth­ing video applications, when analog video is reconstruct­ed from a digital data stream. These devices require a
single +5V supply and the filters have a cutoff frequency
optimized for NTSC, PAL, and standard definition digital
TV (SDTV) video signals. The MAX7428/MAX7430/
MAX7432A feature Maxim’s single-pin bus (MSPB™)
interface to digitally control channel selection (IN_A or
IN_B), adjust high-frequency boost, bypass the filter,
configure luma vs. chroma operation, and control the
output disable. The MAX7428 single-channel filter is
ideal for composite (CVBS) video signals. The MAX7430
dual filter is optimized for S-Video (Y/C) applications. The
MAX7432A triple filter is optimized for component (YPbP

r

or embedded synchronous RGB) video signals. The
MAX7428 is available in a tiny 8-pin SOT23 package, the
MAX7430 is available in a miniature 10-pin µMAX®pack­age, and the MAX7432A is available in a 14-pin TSSOP
package. The MAX7428/MAX7430/MAX7432A are fully
specified over the -40°C to +85°C extended temperature
range.

Applications

Set-Top Boxes

DVD Players

Hard-Disk Recorders

Camcorders

Features

♦ Ideal for CVBS, Y/C (S-Video), and RGB (Y PbPr)

Outputs for NTSC, PAL, and SDTV

♦ 6th-Order Lowpass Filter

♦ Drives Two 150Ω Video Loads

♦ Four Levels of Passband High-Frequency

Boost Control

♦ Input 2 to 1 Multiplexer

♦ Output Disable

♦ Filter Bypassing

♦ +5V Single-Supply Voltage

♦ Tiny 8-Pin SOT23 Package (MAX7428), 10-Pin

µMAX Package (MAX7430), and 14-Pin TSSOP
Package (MAX7432A)

MAX7428/MAX7430/MAX7432A

Standard Definition Video Reconstruction

Filters and Buffers

________________________________________________________________ Maxim Integrated Products 1

+6dB

LEVEL SHIFT

6TH-ORDER

FILTER

OUT

SERIAL INTERFACE

AND CONTROL

DATA

D/A

INA

INB

*

*OPTIONAL

SYNC

AUX INPUT

BIAS GENERATOR

GND

REXT

ENCODER

MAX7428

SYNCIO

V

CC

75Ω

75Ω

C

IN

C

IN

*

Functional Diagrams

Ordering Information

xx-xxxx; Rev 0; 2/06

Pin Configurations appear at end of data sheet.

Functional Diagrams continued at end of data sheet.

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

TEMP

RANGE

PIN-

TOP

MARK

MAX7428EKA-T

8 SOT23-8 AAIU

MAX7430EUB

10 µMAX —

MAX7432AEUD

14 TSSOP —

MSPB is a trademark of Maxim Integrated Products, Inc.
µMAX is a registered trademark of Maxim Integrated Products, Inc.

PACKAGE

-40°C to +85°C

-40°C to +85°C

-40°C to +85°C

MAX7428/MAX7430/MAX7432A

Standard Definition Video Reconstruction
Filters and Buffers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC= +5V ±10%, R

REXT

= 300kΩ ±1%, CIN= 0.1µF, C

REXT

= (1nF to 1µF) ±1%, C

LOAD

= 0 to 20pF; BOOST0_, BOOST1_ = 0, 0;

T

A

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Note 2)

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.

VCCto GND ...........................................................................+6V

All Other Pins to GND.................................-0.3V to (V

CC

+ 0.3V)

Maximum Current Into Any Pin .........................................

±

50mA

Continuous Power Dissipation (T

A

= +70°C)

8-Pin SOT23 (derate 9.71mW/°C above +70°C)..........777mW

10-Pin µMAX (derate 6.94mW/°C above +70°C) ......555.5mW

14-Pin TSSOP (derate 9.1mW/°C above +70°C) .........727mW

Operating Temperature Range ...........................-40°C to +85°C

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

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

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

PARAMETER

CONDITIONS

UNITS

f = 100kHz to 4.2MHz relative to 100kHz

Passband Response

f = 100kHz to 5MHz relative to 100kHz

dB

Stopband Attenuation A

sb

f

>

27MHz 48 dB

HF Boost Relative Step Size, 4
Levels

f = 4.2MHz to 5MHz 0.2 0.4 0.6 dB

Differential Gain dG 5-step modulated staircase 0.2 %

Differential Phase dθ 5-step modulated staircase 0.2

degrees

Harmonic Distortion THD f = 100kHz to 5MHz 0.1 0.5 %

Signal-to-Noise Ratio SNR

Peak signal (2Vp-p) to RMS noise,
f = 100Hz to 50MHz

72 dB

Group Delay Deviation Δt

g

Deviation from 100kHz to 3.58 (4.43)MHz 20 ns

Line-Time Distortion H

dist

18µs, 100 IRE bar 0.3 %

Field-Time Distortion V

dist

130 lines, 18µs, 100 IRE bar 0.5 %

Clamp Settling Time t

clamp

to ±1% (Note 1)

Lines

CLEVEL = 0 0.8 1.3

Output DC Clamp Level

CLEVEL = 1

V

Low-Frequency Gain A

V

Gain at 100kHz 1.9

V/V

Group Delay Matching

f = 100kHz

2ns

Low-Frequency Gain Matching

)

C hannel - to- channel g ai n m atchi ng , f = 100kH z5%

Channel-to-Channel Crosstalk X

TALK

Channel-to-channel crosstalk, f = 100kHz
to 5.5MHz

-60 dB

Output Short-Circuit Current I

SC

OUT_ shorted to ground or V

CC

50 mA

Input Leakage Current I

IN

10 µA

CLEVEL = 0 1.4

Input Dynamic Swing

CLEVEL = 1 0.9

Vp-p

VCC Supply Range V

CC

4.5 5.5 V

SYMBOL

MIN TYP MAX

-0.5 +0.5

-1.0 +1.0

t

g(MATCH)

A

V(MATCH

Y

INp-p

C

INp-p

Low frequency channel-to-channel matching

1.35 1.85

1.975 2.05

100

MAX7428/MAX7430/MAX7432A

Standard Definition Video Reconstruction

Filters and Buffers

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VCC= +5V ±10%, R

REXT

= 300kΩ ±1%, CIN= 0.1µF, C

REXT

= (1nF to 1µF) ±1%, C

LOAD

= 0 to 20pF; BOOST0_, BOOST1_ = 0, 0;

T

A

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Note 2)

MSPB INTERFACE TIMING SPECIFICATIONS

(VCC= +5V ±10%, R

REXT

= 300kΩ ±1%, C

REXT

= (1nF to 1µF) ±1%, C

LOAD

= 0 to 20pF, TA= T

MIN

to T

MAX

, unless otherwise noted.

Typical values are at T

A

= +25°C.) (Figures 4 through 9)

Note 1: One horizontal line = 63.5µs.
Note 2: MAX7428 devices are 100% production tested at T

A

= +25°C and are guaranteed by design from TA= T

MIN

to T

MAX

.

PARAMETER

CONDITIONS

UNITS

MSPB TIMING

Logic-Zero/Prompt Pulse Width t0, t

P

158µs

Logic-One Pulse Width t

1

24 30 36 µs

Transaction Pulse Width t

T

80

µs

Separation Between Pulses t

WAIT

0.5 µs

Bus Release Time by Host After
Prompt Pulse

1µs

Bus Reclaim Time by Host After
Prompt Pulse

13 µs

Read Back Data Valid Window
After the Prompt Pulse

t

READ

2.3 4.7 µs

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Power-Supply Rejection Ratio PSRR V

IN_A/IN_B Crosstalk V

LOGIC CHARACTERISTICS

Logic Input High Voltage V

Logic Input Low Voltage V

Logic Input Current IIH/I

Logic Output High Voltage V

Logic Output Low Voltage V

CC

OH

OL

No load

= 100mVp-p, f = 0 to 5.5MHz 40 dB

IN

= 100mVp-p, f = 100kHz to 5.5MHz -60 dB

IN

IH

IL

VIL = 0 (source), VIH = VCC (sink) 10 µA

IL

I

(SOURCE)

I

(SINK)

= 500µA

= 500µA 0.4 V

SYMBOL

MAX7428 24 32

MAX7430 45 62Supply Current I

MAX7432A 68 86

2V

-

V

CC

0.5

MIN TYP MAX

mA

0.8 V

V

100 120

t

RELEASE

t

RECLAIM

MAX7428/MAX7430/MAX7432A

Standard Definition Video Reconstruction
Filters and Buffers

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VCC= +5V, R

REXT

= 300kΩ; BOOST0_, BOOST1_ = 0, 0; V

IN_

= 1Vp-p, TA= +25°C, unless otherwise noted.)

0.1 1 10 100

AMPLITUDE vs. FREQUENCY

MAX7428/30/32 toc01

FREQUENCY (MHz)

AMPLITUDE (dB)

0

-60

-50

-40

-30

-20

-10

0.1 1 10

PASSBAND AMPLITUDE vs. FREQUENCY

MAX7428/30/32 toc02

FREQUENCY (MHz)

AMPLITUDE (dB)

2

-10

-8

-6

-4

-2

0

A

C

D

B

A: BOOST1, BOOST0 = 1, 1
B: BOOST1, BOOST0 = 1, 0
C: BOOST1, BOOST0 = 0, 1
D: BOOST1, BOOST0 = 0, 0

0.1 1 10

PHASE RESPONSE vs. FREQUENCY

MAX7428/30/32 toc03

FREQUENCY (MHz)

PHASE (DEGREES)

180

-180

-120

-60

0

60

120

0.1 1 10

GROUP DELAY vs. FREQUENCY

MAX7428/30/32 toc04

FREQUENCY (MHz)

GROUP DELAY (ns)

120

0

20

40

60

80

100

200ns/div

2T RESPONSE (1IRE = 7.14mV)

INA_

200mV/div

OUT_

200mV/div

MAX7428/30/32 toc05

400ns/div

MODULATED 12.5T RESPONSE

(1IRE = 7.14mV)

INA_

200mV/div

OUT_

200mV/div

MAX7428/30/32 toc06

22

24

23

26

25

27

28

-40 10-15 356085

SUPPLY CURRENT vs. TEMPERATURE

MAX7428/30/32 toc07

TEMPERATURE (°C)

SUPPLY CURRENT (mA)

NO LOAD

0.2

0.1

0

-0.1

-0.2

-0.3

DIFFERENTIAL GAIN (%)

0 -0.01 -0.04 -0.08 -0.10

-0.06

1st.

2nd.

3rd. 4th.

5th.

6th.

DIFFERENTIAL GAIN

MAX7428/30/32 toc08

MAX7428/30/32 toc09

0.20

0.15

0.10

0.05

0

-0.05
1st.

2nd.

3rd.

4th.

5th. 6th.

0 0.04 0.06

0.06

0.04 0.02

DIFFERENTIAL PHASE (DEGREES)

DIFFERENTIAL PHASE

MAX7428/MAX7430/MAX7432A

Standard Definition Video Reconstruction

Filters and Buffers

_______________________________________________________________________________________ 5

0.1 1 10

OUTPUT IMPEDANCE vs. FREQUENCY

MAX7428/30/32 toc10

FREQUENCY (MHz)

IMPEDANCE (Ω)

0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

200ns/div

OUTPUT TRANSIENT DUE TO

INPUT MUX SWITCHING

OUT_

500mV/div

MAX7428/30/32 toc11

-70

-95

0.1 1 10

PASSBAND CHANNEL-TO-CHANNEL

CROSSTALK vs. FREQUENCY

-90

MAX7428/30/32 toc12

FREQUENCY (MHz)

CROSSTALK (dB)

-85

-80

-75

BOOST = CODE 00

Typical Operating Characteristics (continued)

(VCC= +5V, R

REXT

= 300kΩ; BOOST0_, BOOST1_ = 0, 0; VIN= 1Vp-p, TA= +25°C, unless otherwise noted.)

Pin Description

PIN

MAX7432A

NAME FUNCTION

1 1 — IN1A

Video Input 1A. Master channel, sync signal required. Use a 0.1µF
series input capacitor for proper operation.

2 2 — IN2A

Video Input 2A. Slave channel, clamping controlled by master channel
sync. Use a 0.1µF series input capacitor for proper operation.

3 — — IN3A

Video Input 3A. Slave channel, clamping controlled by master channel
sync. Use a 0.1µF series input capacitor for proper operation.

4, 10 8 4 GND Ground

5 4 — IN1B

Video Input 1B. Master channel, sync signal required. Use a 0.1µF
series input capacitor for proper operation.

6 5 — IN2B

Video Input 2B. Slave channel, clamping controlled by master channel
sync. Use a 0.1µF series input capacitor for proper operation.

7 — — IN3B

Video Input 3B. Slave channel, clamping controlled by master channel
sync. Use a 0.1µF series input capacitor for proper operation.

8 6 6 DATA Serial Data Interface

9 — — OUT3 Buffer Output 3

11 7 — OUT2 Buffer Output 2

12 3 7 REXT

External Resistor. Connect a 300kΩ resistor from REXT to GND for
internal biasing. Connect a 1nF to 1µF capacitor from REXT to GND for
chip-address programming (see Table 3).

MAX7430 MAX7428

D/A

D/A

0.1μF

0.1μF

INA

INB

GND

ENCODER

75Ω

75Ω

75Ω

**220μF

75Ω

C1

300kΩ

SERIAL I/O

SYNC PULSE
IN OR OUT

OUT

V

CC

5V

REXT

DATA

SYNCIO

**220μF

*1MΩ

*1MΩ

MAX7428

Z0 = 75Ω

Z

0

= 75Ω

5V

10kΩ

***

C1 = 1nF TO 1μF (SEE TABLE 3)
*NEEDED ONLY IN FILTER BYPASS MODE
**OPTIONAL CAPACITOR
***ONLY ONE PULLUP RESISTOR NEEDED PER BUS

Figure 1. MAX7428 Typical Application Circuit

MAX7428/MAX7430/MAX7432A

Detailed Description

The MAX7428/MAX7430/MAX7432A filter and buffer the
outputs of DAC encoder chipsets that process digital
video information in applications such as set-top boxes,
hard-disk recorders, DVD players, recorders, and digi­tal VCRs. These devices also filter and “clean-up” ana­log video signals. Each channel in the MAX7428/
MAX7430/MAX7432A includes an input mux to select
the input channel, a 6th-order Sallen-Key filter with four
adjustable high-frequency boost levels, an output
buffer with a 6dB gain, a sync detector and clamp, and
an external resistor to set internal bias levels. Output
disable adds additional multiplexing in a wired-OR con­figuration. Filter bypass, in conjunction with the two
inputs, can be used to provide filtered and unfiltered
video signal processing. Maxim’s Single Pin Bus

(MSPB) interface controls all of the above features. An
external capacitor is used to assign each device a
unique address that allows control of up to 16 devices
on the same bus. Typical application circuits for the
MAX7428/MAX7430/MAX7432A are shown in Figures 1,
2, and 3.

Input Considerations

Use a 0.1µF ceramic capacitor to AC-couple the input
to the MAX7428/MAX7430/MAX7432A. This input
capacitor stores a DC level to level-shift the input signal
to an optimal point between VCCand GND. The ABSEL
bit on the Control Register sets which channel (IN_A or
IN_B) is selected (Control Register section). The IN_A
and IN_B inputs have a typical input resistance of
50kΩ.

Standard Definition Video Reconstruction
Filters and Buffers

6 _______________________________________________________________________________________

Pin Description (continued)

PIN

MAX7432A

NAME FUNCTION

13 9 — OUT1 Buffer Output 1

14 10 2 V

CC

+5V Supply Voltage

— — 1 INA Video Input A. Use a 0.1µF series input capacitor for proper operation.

— — 3 INB Video Input B. Use a 0.1µF series input capacitor for proper operation.
—— 5

Sync Pulse Input or Output

— — 8 OUT Buffer Output

MAX7430 MAX7428

SYNCIO

MAX7428/MAX7430/MAX7432A

Standard Definition Video Reconstruction

Filters and Buffers

_______________________________________________________________________________________ 7

0.1μF

*1MΩ

D/A

0.1μF

*1MΩ

0.1μF

*1MΩ

D/A

0.1μF

*1MΩ

75Ω

Z

0

= 75Ω

Z

0

= 75Ω

75Ω

Z

0

= 75Ω

Z

0

= 75Ω

200μF**

200μF**

75Ω

75Ω

75Ω

75Ω

200μF**

200μF**

75Ω

75Ω

SERIAL I/O

300kΩ

C1

+5V

MAX7430

IN1A

IN1B

IN2A

IN2B

OUT1

OUT2

DATA

REXT

GND

V

CC

ENCODER

ENCODER

+5V

10kΩ

***

C1 = 1nF TO 1μF (SEE TABLE 3)
*NEEDED ONLY IN FILTER BYPASS MODE
**OPTIONAL OUTPUT CAPACITOR
***ONLY ONE PULLUP RESISTOR NEEDED PER BUS

AUX IN

AUX IN

Figure 2. MAX7430 Typical Application Circuit