FMS6141 — Low-Cost, Single-Channel 4
th
-Order Standard Definition Video Filter Driver
November 2012
FMS6141
Low-Cost, Single-Channel 4
th
-Order
Standard Definition Video Filter Driver
Features
Single 4th-Order 8 MHz (SD) Filter
Drives Single, AC- or DC-coupled, Video Loads
(2 V
pp
, 150
Ω)
Description
The FMS6141 Low-Cost Video Filter is intended to
replace passive LC filters and drivers with a low-cost
integrated device. The 4th-order filter provides improved
image quality compared to typical 2nd or 3rd-order
passive solutions.
The FMS6141 may be directly driven by a DC-coupled
DAC output or an AC-coupled signal. Internal diode
clamps and bias circuitry may be used if an AC-coupled
input is required
(see Application Information for details).
The FMS6141’s output can drive an AC- or DC-coupled
single (150
Ω)
or dual (75
Ω)
load. DC-coupling the
output removes the need for output coupling capacitors.
The input DC level is offset approximately +280 mV at
the output (see
Application Information for details).
Drives Dual, AC- or DC-coupled, Video Loads
(2V
pp
, 75Ω)
Transparent Input Clamping
AC- or DC-Coupled Input
AC- or DC-Coupled Output
DC-Coupled Output Eliminates AC-Coupling
Capacitors
Single Supply
Robust 8 kV ESD Protection
Lead-Free Packages: SOIC-8 or SC70-5
Related Applications Notes
AN-6041 PCB Layout Considerations for Video
Filter / Drivers
Applications
Cable Set-Top Boxes
Satellite Set-Top Boxes
DVD Players
HDTVs
Personal Video Recorders (PVR)
Video On Demand (VOD)
Functional Block Diagram
AN-6024 FMS6xxx Product Series Understanding
Analog Video Signal Clamps, Bias, DC-Restore,
and AC or DC Coupling Methods
VIDEOIN
Transparent Clamp
2X
VIDEO T
OU
8MHz, 4th-order
Figure 1. Block Diagram
© 2006 Fairchild Semiconductor Corporation
FMS6141 Rev. 1.0.3
www.fairchildsemi.com
FMS6141 — Low-Cost, Single-Channel 4
th
-Order Standard Definition Video Filter Driver
Ordering Information
Part Number
FMS6141CSX
FMS6141S5X
Operating
Temperature Range
-40°C to +85°C
-40°C to +85°C
Package
8-Lead, Small Outline Integrated Circuit (SOIC)
5- Lead SC70 Package
Packing
Method
Tape and Reel
Tape and Reel
Pin Configurations
VIN 1
N/C
GND
N/C
2
3
4
Figure 2. SOIC-8
8
7
6
5
VOUT
VCC
N/C
N/C
GND
GND
1
2
FMS6141
SC70-5
4
Figure 3. SC70
FMS6141
SOIC-8
5
VCC
VIN 3
VOUT
Pin Definitions
SOIC Pin #
1
2
3
4
5
6
7
8
5
4
1, 2
SC70 Pin#
3
Name
V
IN
N/C
GND
N/C
N/C
N/C
V
CC
V
OUT
Video Input
No Connect
Description
Must Be Connected to Ground
No Connect
No Connect
No Connect
+5V Supply, Do Not Float
Filtered Video Output
© 2006 Fairchild Semiconductor Corporation
FMS6141 Rev. 1.0.3
www.fairchildsemi.com
2
FMS6141 — Low-Cost, Single-Channel 4
th
-Order Standard Definition Video Filter Driver
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability.
The absolute maximum ratings are stress ratings only.
Symbol
V
CC
V
IO
I
OUT
DC Supply Voltage
Parameter
Analog and Digital I/O
Output Current, Do Not Exceed
Min.
-0.3
-0.3
Max.
6.0
V
CC
+0.3
50
Unit
V
V
mA
Recommended Operating Conditions
Symbol
T
A
V
CC
V
CC
Range
Parameter
Operating Temperature Range
Min.
-40
4.75
Typ.
5.00
Max.
85
5.25
Unit
°C
V
ESD Information
Symbol
ESD
Parameter
Human Body Model, JESD22-A114
Charged Device Model, JESD22-C101
Value
8.0
1.5
Unit
kV
kV
Reliability Information
Symbol
T
J
T
STG
T
L
Θ
JA
Junction Temperature
Storage Temperature Range
Lead Temperature (Soldering, 10 s)
Thermal Resistance
(JEDEC Standard Multi-Layer Test Boards, Still Air)
SOIC-8
SC70-5
115
332
-65
Parameter
Min.
Typ.
Max.
+150
+150
300
Unit
°C
°C
°C
°C/W
°C/W
© 2006 Fairchild Semiconductor Corporation
FMS6141 Rev. 1.0.3
www.fairchildsemi.com
3
FMS6141 — Low-Cost, Single-Channel 4
th
-Order Standard Definition Video Filter Driver
DC Specifications
T
A
= 25°C, V
CC
= 5.0 V, R
S
= 37.5
Ω;
input is AC coupled with 0.1 µF; output is AC coupled with 220 µF into a 150
Ω
load; unless otherwise noted.
Symbol
I
CC
V
IN
PSRR
Parameter
Supply Current
(1)
Video Input Voltage Range
Power Supply Rejection Ratio
No Load
Conditions
Referenced to GND if DC-
Coupled
DC
Min.
Typ.
7
1.4
40
Max.
12
Unit
mA
V
pp
dB
Note:
1. 100% tested at 25°C
AC Electrical Specifications
T
A
= 25°C, V
CC
= 5.0 V, R
S
= 37.5
Ω;
input is AC coupled with 0.1 µF; output is AC coupled with 220 µF into a 150
Ω
load; unless otherwise noted.
Symbol
AV
f
1dB
f
C
f
SB
dG
dφ
THD
SNR
t
pd
Parameter
Channel Gain
(2)
-1dB Bandwidth
(2)
-3dB Bandwidth
Attenuation (Stopband Reject)
Differential Gain
Differential Phase
Output Distortion (all channels)
Signal-to-Noise Ratio
Propagation Delay
Conditions
Min.
5.6
4.0
Typ.
6.0
6.5
7.7
42
0.4
0.4
Max.
6.4
Unit
dB
MHz
MHz
dB
%
°
%
dB
ns
f = 27 MHz
V
OUT
= 1.8 V
pp
, 1 MHz
NTC-7 Weighting; 100 kHz to
4.2 MHz
Delay from input to output,
4.5 MHz
0.4
75
55
Note:
2. 100% tested at 25°C
© 2006 Fairchild Semiconductor Corporation
FMS6141 Rev. 1.0.3
www.fairchildsemi.com
4
FMS6141 — Low-Cost, Single-Channel 4
th
-Order Standard Definition Video Filter Driver
Application Information
Input Considerations
The FMS6141 Low-Cost Video Filter provides 6 dB (2X)
gain from input to output. The device provides an
internal diode clamp to support AC-coupled input
signals. In this configuration, a 0.1 µF ceramic capacitor
is used to AC couple the input signal. If the input signal
does not go below ground, the clamp is inactive; but if
the input signal goes below ground, the clamp circuitry
sets the bottom of the sync tip (or lowest voltage) to just
below ground. The input level set by the clamp,
combined with the internal DC offset, keeps the output
signal within an acceptable range. This clamp feature
also allows the FMS6141’s input to be directly driven
(DC-coupled) by a ground referenced DAC output.
Figure 4 shows typical DC voltage levels for the input
and output signals when driven by a DC-coupled DAC
output or an AC-coupled and clamped Y, CV signal.
1.0 -> 1.02V
0.65 -> 0.67V
0.3 -> 0.32V
0.0 -> 0.02V
Vin
2.28V
1.58V
0.88V
0.28V
Vout
Output Considerations
The FMS6141 outputs will be DC offset from the input
by 150 mv therefore V
OUT
= 2*V
IN
DC+150 mv. This
offset is required to obtain optimal performance from the
output driver and is held at the minimum value in order
to decrease the standing DC current into the load. Since
the FMS6141 has a 2x (6 dB) gain, the output is typically
connected via a 75
Ω
series back-matching resistor
followed by the 75
Ω
video cable. Because of the
inherent divide by two of this configuration, the blanking
level at the load of the video signal is always less then
1 V. When AC-coupling the output ensure that the
coupling capacitor of choice will pass the lowest
frequency content in the video signal and that line time
distortion (video tilt) is kept as low as possible.
The selection of the coupling capacitor is a function of
the subsequent circuit input impedance and the leakage
current of the input being driven. In order to obtain the
highest quality output video signal the series termination
resistor must be placed as close to the device output pin
as possible. This greatly reduces the parasitic
capacitance and inductance effect on the FMS6141
output driver. Recommend distance from device pin to
place series termination resistor should be no greater
than 0.1 inches.
Figure 4. Typical DC Voltage Levels
Figure 5. Distance from Device Pin to Series
Termination Resistor
© 2006 Fairchild Semiconductor Corporation
FMS6141 Rev. 1.0.3
www.fairchildsemi.com
5
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
