Rainbow Electronics MAX7445 - Manual

General Description
The MAX7445 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 MAX7445 has three modes of operation. Mode 1
processes CVBS and RGB video signals. Mode 2
processes CVBS, Y, and C signals, as well as a second
asynchronous CVBS video signal. Mode 3 processes
RGB and CVBS (asynchronous) video signals. An exter-
nal pin adjusts the gain of the video buffer to either +6dB,
+9.5dB, or +12dB to accommodate video-encoder DAC
output signals of <1V. High-frequency boost circuitry pro-
vides picture sharpness with +1.2dB of gain boost with-
out degradation in the stopband. The output video drivers
can be disabled with an external pin.
The MAX7445 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 CVBS, RGB, or Y/C
Video 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
♦ Selectable Gain: +6dB, +9.5dB, and +12dB
♦ Small 14-Pin TSSOP Package
MAX7445
4-Channel Video Reconstruction Filter
________________________________________________________________ Maxim Integrated Products 1
GAIN
V CC
GND
MAX7445
OUTA
*
*
OUTB
*
*
OUTC
*
*
OUTD
*
*
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
75 Ω
*OPTIONAL CAPACITORS
INA
0.1 µF
0.1 µF
0.1 µF
0.1 µF
INB
INC
IND
D/A
ENCODER
D/A
D/A
D/A
SYNC
DETECTOR
LOWPASS
FILTER
LOWPASS
FILTER
LOWPASS
FILTER
LOWPASS
FILTER
SYNC
DETECTOR
DISABLE
SELECT
Functional Diagram
Ordering Information
19-2948; 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
MAX7445EUD -40°C to +85°C 14 TSSOP-EP*