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ML6426
High Bandwidth Triple Video Filters with Buffered
Outputs for RGB or YUV
Features
• 5V ±10% operation
• RGB/YUV filters for ATSC Digital Television VESA
Standard
• 2:1 Mux Inputs for multiple RGB/YUV inputs
• Triple Reconstruction Filter options for 6.7, 12, 24, 30,
and 36MHz to handle various line rates
• Multiple ML6426 outputs can be paralleled to drive RGB/
YUV outputs at different frequencies for various line rates
by means of Disable/Enable pin.
• 6dB drivers and sync tip clamps for DC restore
• DC restore with minimal tilt
• 0.4% differential gain on all channels
0.4º differential phase on all channels
0.8% total harmonic distortion on all channels
• 2kV ESD protection
General Description
The ML6426 are a family of triple video filters with buffered
outputs. There are several versions of the ML6426, each with
different passband cut-off frequencies of 6.7MHz, 12MHz,
24MHz, 30MHz, and 36MHz. Each channel contains a 4
th
-
order Butterworth lowpass reconstruction video filter. The
filter is optimized for minimum overshoot and flat group
delay and guaranteed differential gain and phase at the out-
puts of the integrated cable drivers.
All input signals from DACs are AC coupled into the
ML6426. All channels have DC restore circuitry to clamp the
DC input levels during video H-sync, using an output feed-
back clamp. An external H-sync signal is required for this
purpose.
All outputs must be AC coupled into their loads. Each output
can drive 2V
P-P
into a 150
Ω
load. All channels have a gain of
2 (6dB) at 1V
P-P
input levels.
Block Diagram
12
VCCO
RINA/YINA
RINB/YINB
GINA/UINA
GIN/UINB
BINA/VINA
BINB/VINB
MUX
TRANSCONDUCTANCE
ERROR AMP
A/B MUX
1
SYNCIN
16
DISABLE
15
GNDO
14
GND
3
+
–
4
VCC
2
5
6
7
8
9
MUX
TRANSCONDUCTANCE
ERROR AMP
MUX
TRANSCONDUCTANCE
ERROR AMP
+
–
+
–
4th-ORDER
FILTER A
0.5V
4th-ORDER
FILTER B
0.5V
4th-ORDER
FILTER C
0.5V
×2
ROUT/YOUT
13
×2
GOUT/UOUT
11
×2
BOUT/VOUT
10
ML6426-1
Filter A
Filter B
Filter C
6.7MHz
6.7MHz
6.7MHz
ML6426-2
12MHz
12MHz
12MHz
ML6426-3
24MHz
24MHz
24MHz
ML6426-4
30MHz
30MHz
30MHz
ML6426-5
36MHz
36MHz
36MHz
ML6426-15
15MHz
15MHz
15MHz
REV. 3A August 2004
FAIRCHILD [ FAIRCHILD SEMICONDUCTOR ]
