Fairchild Semiconductor FMS6413 Datasheet
www.fairchildsemi.com
FMS6413
Single Channel Video Driver with Integrated Filter
and Clamp
Video Features
• Integrated Video Low Pass reconstruction filter
• Integrated output driver provides a low impedance output
and delivers 2Vp-p (6dB gain) composite video into
150 Ω .
• 7.1MHz 4
• 0.4% differential gain with 0.4° differential phase
• Integrated DC Restore / Clamp Circuitry
th
order video filter
Applications
• CCTV
• DVD players
• Televisions
• HDTV
• Personal Video Recorders (PVRs)
• Video On Demand (VOD)
• Cable and Satellite Set top boxes
Block Diagram
SYNC STRIP,
REFERENCE,
AND TIMING
General Description
The FMS6413 Single Channel Video Filter – Driver Chip
offers comprehensive video filtering for set top box or DVD
applications. This part consists of a 4
Pass filter for video filtering. This device integrates a video
driver so that it can directly driv e to the outside world. There
is also an integrated clamp circuit that allows the part to DC
restore.
The video output is filtered at 7.1MHz and buffered to drive
2Vp-p into an AC coupled 150 Ω load with up to 35pF of
load capacitance at the output pin. The filter approximates a
4th-order Butterworth characteristic with an optimization
toward low overshoot and flat group delay. Likewise, the
driver is capable of driving a 75 Ω load at 1Vp-p. There is an
option for the video output to be DC coupled which limits
the drive to 1 output.
th
order video Low
VIDEO_IN
gM
1V
x2
VIDEO_OUT
REV. 1.0.2 6/27/02
Pin Configuration
FMS6413
FMS6413
8-Pin SOIC (S08)
1
VIDEO_IN
2
NC
3
GND_VIDEO
4
NC
VIDEO_OUT
VCC_VIDEO
NC
NC
8
7
6
5
Pin Description
Video Section
Pin# Pin Type Description
1 VIDEO_IN Input Video Input
8 VIDEO_OUT Output Video Output: This pin is the filtered video output
Power/Ground Pins
Pin# Pin Type Description
7 VCC_VIDEO Power +5 VDC for Video
3 GND_VIDEO Power Ground for Video
4 NC NC Reserved (Need to Float)
5 NC NC Reserved (Need to Float)
6 NC NC Reserved (Need to Float)
2 NC NC Reserved (Need to Float)
2
REV. 1.0.2 6/27/02
FMS6413
Functional Description
Introduction
The FMS6413 is a monolithic continuous time video filter driver designed for reconstructing the video signals from a
D/A source. This chip is intended for use in applications
with AC coupled input and AC coupled outputs. (See
Figure 1) The reconstruction filter approximates a 4th-order
Butterworth characteristic with an optimization toward low
over-shoot and flat group delay. The video output is capable
of driving 2VP-P into an AC coupled 150 Ω video load, with
up to 35pF of load capacitance at the output pin. The channel
is clamped during sync to establish the appropriate output
voltage swing range. Thus the input coupling capacitor does
not behave according to the conventional RC time constant.
Clamping for the video channel settles to less than 10mv
within 5ms of a change in video input source. In most
applications the input coupling capacitor is 0.1µF. The input
typically sinks 1µA during active video, which nominally
tilts a horizontal line by about 2mV at the Video output.
During sync, the clamp typically sources 20µA to restore the
Typical Applications Diagram
VIDEO_IN
0.1µF
1
VIDEO_IN VIDEO_OUT
2
NC (Reserved)
SYNC STRIP,
REF, AND TIMING
gM
1V
FMS6413
x2
VCC_VIDEO
DC level. The net result is that the average input current is
zero. An y change in the input coupling capacitor’s value will
inversely alter the amount of tilt per line. Such a change will
also linearly affect the clamp response time. This product is
robust and stable under all stated load and input conditions.
Capacitive bypassing VCC directly to ground ensures this
performance.
Video I/O
The video input is driven by either a low impedance source
of 1VP-P or the output of a 75 Ω terminated line. The input is
required to be AC coupled via a 0.1µF coupling capacitor
which allows for a settling time of 5ms. The video output is
capable of driving an AC coupled 150 Ω load at 2VP-P, or
1VP-P into a 75 Ω load. Up to 35pF of load capacitance
(at the output pin) can be driven without stability or slew
issues. The output is AC coupled with a 220µF or larger AC
coupling capacitor.
220µF
8
7
75Ω
0.1µF
Video Cable
+5.0V
1µF
VIDEO_OUT
75Ω
REV. 1.0.2 6/27/02
3
GND_VIDEO
4
NC (Reserved) NC (Reserved)
NC (Reserved)
Figure 1.
6
5
3
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