Rainbow Electronics MAX7457 - Manual

General Description
The MAX7457 4-channel video switch is ideal for anti-
aliasing and DAC-smoothing video applications or wher-
ever analog video is reconstructed from a digital data
stream such as cable/satellite/terrestrial set-top boxes
(STBs), DVD players, hard disk recorders (HDRs), and
personal video recorders (PVRs). The MAX7457 filters
and buffers CVBS and RGB video signals, making it
ideal for dual SCART (peritelevision) STBs with an
auxiliary CVBS input. The MAX7457 operates from a sin-
gle +5V supply and has a flat passband out to 5MHz
with a stopband attenuation of 43dB at 27MHz, making
it ideal for NTSC, PAL, and standard-definition digital TV
(SDTV) video systems.
The MAX7457 output buffers have a fixed gain of +6dB
and are capable of driving two standard 150
Ω video
loads. The channel for CVBS video has high-frequency
boost circuitry that enhances picture sharpness with up
to +1.2dB of gain boost without degradation in the
stopband. The video output drivers can be disabled by
an external control input.
The MAX7457 is available in a 16-pin, 5mm x 5mm x
0.8mm TQFN package, and is specified over the
extended (-40°C to +85°C) temperature range.
Applications
STBs/HDRs DVD Players
Game Consoles Digital VCRs
Desktop Video Editors
Features
♦ 4-Channel Video Filter/Buffer for RGB and CVBS
Signals with Auxiliary Input
♦ Allows Auxiliary Input for CVBS Video Loop-
Through Applications
♦ 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 Operation
♦ Available in 5mm x 5mm x 0.8mm, 16-Pin TQFN
MAX7457
Video Switch for Dual SCART Connectors
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
MAX7457
75 Ω
75 Ω
*
*
75 Ω
75 Ω
OUTA
+6dB
75 Ω
75 Ω
*
*OPTIONAL CAPACITORS
*
75 Ω
75 Ω
OUTB
+6dB
75 Ω
75 Ω
*
*
75 Ω
75 Ω
OUTC
+6dB
75 Ω
75 Ω
*
*
75 Ω
75 Ω
OUTD
+6dB
SYNC
DETECTOR
LOWPASS
FILTER
LOWPASS
FILTER
LOWPASS
FILTER
LOWPASS
FILTER
2-TO-1
MUX
GND
DISABLE
SELA
V CC
0.1 µF
INA2
0.1 µF
INA1
0.1 µF
INB
0.1 µF
INC
0.1 µF
IND
D/A
D/A
D/A
D/A
AUXILIARY VIDEO SOURCE
(VCR, DVD, ETC.)
ENCODER
CVBS
R
B
G
Typical Operating Circuit
19-3560; Rev 0; 1/05
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.
Pin Configuration appears at end of data sheet.
PART TEMP RANGE PIN-PACKAGE
PKG
CODE
MAX7457ETE -40°C to +85°C 16 TQFN-EP* T1655-2
*EP = Exposed pad.