MAX7457 Datasheet, PDF (1/3 Pages) Maxim Integrated Products – Video Switch for Dual SCART Connectors

Preliminary Data
Video Switch for Dual SCART Connectors
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 auxil-
lary CVBS input. The MAX7457 operates from a single
+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 150Ω 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
Ordering Information
PART
TEMP RANGE
MAX7457ETE -40°C to +85°C
*EP = Exposed pad.
PIN-PACKAGE
PKG
CODE
16 TQFN-EP* T1655-2
Pin Configuration appears at end of data sheet.
Typical Operating Circuit
AUXILIARY VIDEO SOURCE
(VCR, DVD, ETC.)
ENCODER
CVBS D/A
SELA
0.1µF
INA2
0.1µF
INA1
2-TO-1
MUX
R D/A
0.1µF
INB
VCC
LOWPASS
FILTER
SYNC
DETECTOR
+6dB
LOWPASS
FILTER
+6dB
0.1µF
G D/A
INC
LOWPASS
FILTER
+6dB
B D/A
0.1µF
IND
LOWPASS
FILTER
MAX7457
+6dB
GND
DISABLE
75Ω
75Ω
*
OUTA
75Ω
75Ω
*
75Ω
75Ω
*
OUTB
75Ω
75Ω
*
75Ω
75Ω
*
OUTC
75Ω
75Ω
*
75Ω
75Ω
*
OUTD
75Ω
75Ω
*
*OPTIONAL CAPACITORS
________________________________________________________________ Maxim Integrated Products 1
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.