Rainbow Electronics MAX7446 User Manual

General Description

The MAX7446 4-channel, buffered video reconstruction
filter is ideal for anti-aliasing and DAC-smoothing video
applications or wherever analog video is reconstructed
from a digital data stream (such as cable/satellite/ter­restrial set-top boxes, DVD players, hard disk recorders
(HDRs), and personal video recorders (PVRs)). This
device operates from a single +5V supply and has a
flat passband out to 5MHz with a stopband attenuation
of 43dB at 27MHz. This makes it ideal for use with
NTSC, PAL, and standard-definition digital TV (SDTV)
video systems. Each output is capable of driving two
standard 150Ω video loads.

The MAX7446 processes CVBS and RGB video signals.
The video output buffers have a fixed gain of +6dB. The
channel for CVBS video has high-frequency boost circuitry
that provides picture sharpness with +1.2dB of gain
boost without degradation in the stopband. The output
video drivers can be disabled with an external pin.

The MAX7446 is available in a 14-pin TSSOP package
with an exposed pad, and is specified over the -40°C to
+85°C extended temperature range.

Applications

Set-Top Boxes/HDRs Game Consoles

Desktop Video Editors DVD Players

Digital VCRs

Features

♦ 4-Channel Filter and Buffer for RGB and

CVBS Signals

♦ Filter Response Ideal for NTSC, PAL, and

Interlaced SDTV Video Signals

♦ 43dB (typ) Stopband Attenuation at 27MHz

♦ ±0.75dB (max) Passband Ripple Out to 5MHz

♦ Blanking Level Voltage on Cable <1V

♦ Each Channel Drives Two 150Ω Video Loads

♦ +5V Single-Supply Voltage

♦ Small 14-Pin TSSOP Package

MAX7446

4-Channel Video Filter for RGB and CVBS Video

________________________________________________________________ Maxim Integrated Products 1

Functional Diagram

Ordering Information

19-2951; Rev 0; 8/03

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.

*EP = Exposed pad.

Pin Configuration appears at end of data sheet.

PART TEMP RANGE PIN-PACKAGE

MAX7446EUD -40°C to +85°C 14 TSSOP-EP*

*

*

*

*

*

*

*

*

75Ω

75Ω

75Ω

75Ω

75Ω

75Ω

75Ω

75Ω

ENCODER

CVBS

(WITHOUT SYNC)

V

CC

0.1µF

0.1µF

0.1µF

0.1µF

INA

INB

INC

IND

D/A

R

D/A

G

D/A

B

D/A

LOWPASS

FILTER

LOWPASS

FILTER

LOWPASS

FILTER

LOWPASS

FILTER

SYNC

DETECTOR

GND

MAX7446

DISABLE

75Ω

OUTA

75Ω

75Ω

OUTB

75Ω

75Ω

OUTC

75Ω

75Ω

OUTD

75Ω

*OPTIONAL CAPACITORS

MAX7446

4-Channel Video Filter for RGB and CVBS Video

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V

CC

= +5V ±5%, CL= 0 to 20pF, RL= 75Ω to GND for DC-coupled load, RL= 75Ω to V

CC

/ 2 for AC-coupled load, C

IN_

= 0.1µF,

T

A

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VCC= +5V, TA= +25°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.

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

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

CC

+ 0.3V)

Maximum Current into Any Pin Except V

CC

and GND .....±50mA

Continuous Power Dissipation (T

A

= +70°C)

TSSOP-EP (derate 20.8mW/°C above +70°C)...........1667mW

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 SYMBOL CONDITIONS MIN TYP MAX UNITS

Passband Response

Stopband Attenuation A

Differential Gain dG 5-step modulated staircase 0.15 0.50 %

Differential Phase dθ 5-step modulated staircase 0.15 0.50 D eg r ees

Signal-to-Noise Ratio SNR

Group Delay Deviation

Line-Time Distortion H

Field-Time Distortion V

Clamp Settling Time t

Output DC Clamp Level

Low-Frequency Gain Accuracy A

Low-Frequency Gain Matching A

Group Delay Matching

Channel-to-Channel Crosstalk X

Output Short-Circuit Current I

Input Leakage Current I

Input Dynamic Swing

SUPPLY

Supply Voltage Range V

Supply Current I

Power-Supply Rejection Ratio PSRR V

f = 100kHz to 5MHz,
relative to 100kHz

f ≥ 27MHz 39 43 dB

SB

Peak signal (2V
f = 100Hz to 50MHz

∆t

DIST

DIST

CLAMP

Deviation from 100kHz

g

to 4.1MHz

18µs, 100 IRE bar 0.3 %

130 lines, 18µs, 100 IRE bar 0.5 %

To ±1% 100 Lines

Channel A 0.6 0.9 1.1

Channels B, C, D 1.1 1.5 1.8

f = 100kHz -3 +3 %

V

V ( M ATC H )

t

g(MATCH)

TALK

Low-frequency channel-to-channel matching,
f = 100kHz

Low-frequency channel-to-channel matching,
f = 100kHz

f = 100kHz to 3.58MHz 60 dB

OUT_ shorted to GND or V

SC

IN

Channel A 1.2

Channels B, C, D 0.9

CC

No load 100 140 mA

CC

= 100mV

IN

P-P

Channel A 0.9 1.2 1.5

Channels B, C, D -0.75 +0.15 +0.75

) to RMS noise,

P-P

80 dB

Channel A 17 30

Channels B, C, D 11 20

4%

2ns

CC

70 mA

10 µA

4.75 5.25 V

, f = 0 to 3.5MHz 40 dB

dB

ns

V

V

P-P