Rainbow Electronics MAX7447 User Manual

General description, Applications, Features

General Description

The MAX7447 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/ter-
restrial 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 150

Ω video loads.

The MAX7447 processes S-Video and CVBS video sig-
nals. The video output buffers have a fixed gain of +6dB.
Each channel has high-frequency boost circuitry that pro-
vides picture sharpness with up to +1.2dB of gain boost
without degradation in the stopband. The output video
drivers can be disabled with an external pin.

The MAX7447 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

DVD Players

Game Consoles

Digital VCRs

Desktop Video Editors

Features

♦ 4-Channel Filter and Buffer for S-Video 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 Output <1V
♦ Each Channel Drives Two 150Ω Video Loads
♦ +5V Single-Supply Voltage
♦ Small 14-Pin TSSOP Package

MAX7447

4-Channel S-Video, CVBS Video Filter with

Asynchronous CVBS Input

________________________________________________________________ Maxim Integrated Products

DISABLE

GND

MAX7447

OUTA

OUTB

OUTC

OUTD

Ω

*OPTIONAL CAPACITORS

INA

0.1

µF

0.1

µF

0.1

µF

0.1

µF

INB

INC

IND

D/A

ENCODER

CVBS

D/A

SYNC

DETECTOR

LOWPASS

FILTER

LOWPASS

FILTER

LOWPASS

FILTER

LOWPASS

FILTER

SYNC

DETECTOR

Functional Diagram

Ordering Information

19-2950; 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

MAX7447EUD

-40°C to +85°C

14 TSSOP-EP*