FMS6400-1 Datasheet, PDF (1/8 Pages) Fairchild Semiconductor – Dual Channel Video Drivers with Integrated Filters and Composite Video Summer

June 2005
FMS6400-1
Dual Channel Video Drivers with Integrated Filters and
Composite Video Summer
Features
■ 5.0 MHz 5th order Y,C filters with composite summer
■ Selectable for 0dB or 6dB gain
■ 50dB stopband attenuation at 27MHz on Y, C and CV outputs
■ No external frequency selection components or clocks
■ AC-Coupled Inputs
■ AC or DC-Coupled Outputs
■ Continuous time low pass filters
■ 0.4% / 0.4° differential gain/phase on Y,C and CV channels
■ Integrated DC restore circuitry with low tilt
■ Lead (Pb) Free SOIC-8 Package
Applications
■ Cable and Satellite set top boxes
■ DVD players
■ Personal Video Recorders (PVR)
■ Video On Demand (VOD)
Description
The FMS6400-1 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. 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 feed-
back 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 can be selected for 0dB or 6dB with 1V_pp input levels. All
video channels are clamped during sync to establish the appro-
priate output voltage reference levels.
Block Diagrams
YIN 1
Sync Strip
Reference and
Timing
VCC
7
0 or
6dB
8 YOUT
CIN 4
gM
250mV
+
S
+
gM
250mV
0 or
6dB
3
GND
6 CVOUT
2
ASEL
5 COUT
©2004 Fairchild Semiconductor Corporation
1
FMS6400-1 Rev. 1A
www.fairchildsemi.com