FMS6406 Datasheet, PDF (1/1 Pages) Fairchild Semiconductor – Precision S-Video Filter with Summed Composite Output, Sound Trap, and Group Delay Compensation

August 2005
FMS6406
Precision S-Video Filter with Summed Composite Output,
Sound Trap, and Group Delay Compensation
Features
■ 7.6MHz 5th order Y,C filters with composite summer
■ 14dB notch at 4.425MHz to 4.6MHz for sound trap
capable of handling stereo
■ 50dB stopband attenuation at 27MHz on Y, C and CV outputs
■ Better than 0.5dB flatness to 4.2MHz on Y, C and CV outputs
■ Equalizer and notch filter for driving RF modulator with group
delay of -180ns
■ No external frequency selection components or clocks
■ < 5ns group delay on Y, C and CV outputs
■ AC coupled inputs
■ AC or DC coupled outputs
■ Capable of PAL frequency for Y,C,CV
■ Continuous Time Low Pass Filters
■ < 1.4% differential gain with 0.7° differential phase on Y, C
and CV channels
■ Integrated DC restore circuitry with low tilt
Applications
■ Cable set-top boxes
■ Satellite set-top boxes
■ DVD players
Description
The FMS6406 is a dual Y/C 5th order Butterworth lowpass
video filter optimized for minimum overshoot and flat group
delay. The device also contains a summing circuit to generate filtered
composite video, an audio trap and group delay compensation
circuit. The audio trap removes video information in the spectral
location of the subsequent RF audio carrier. The group delay
circuit predistorts the signal to compensate for the inherent
receiver IF filter’s group delay distortion.
In a typical application, the Y and C input signals from DACs are
AC coupled into the filters. Both channels have DC restore circuitry to
clamp the DC input levels during video sync. The Y and C channels
use separate feedback clamps. The clamp pulse is derived from
the Y channel.
All outputs are capable of driving 2V_pp, AC or DC coupled, into
either a single or dual video load. A single video load consists of
a series 75Ω impedance matching resistor connected to a ter-
minated 75Ω line, this presents a total of 150Ω of loading to the
part. A dual load would be two of these in parallel which would
present a total of 75Ω to the part. The gain of the Y, C and CV
signals is 6dB with 1V_pp input levels. All video channels are
clamped during sync to establish the appropriate output voltage
reference levels.
Ordering Information
Model
Part Number
FMS6406
FMS6406
FMS6406CS
FMS6406CSX
Temperature range for all parts: 0°C to +70°C.
Lead
Free
Yes
Yes
Package
SOIC-8
SOIC-8
Container
Pack Qty
Tube
Tape and Reel
95
2500
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICES TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY,
FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED
HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN
APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or systems which, (a) are intended for
surgical implant into the body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with instructions for use provided in
the labeling, can be reasonably expected to result in a significant injury of the user.
2. A critical component in any component of a life support device or system whose
failure to perform can be reasonably expected to cause the failure of the life
support device or system, or to affect its safety or effectiveness.
FMS6406 Rev. 4C
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©2005 Fairchild Semiconductor Corporation