August 1999
PRELIMINARY
ML6427
75W Quad Video Cable Drivers and Filters
with Switchable Inputs
GENERAL DESCRIPTION
The ML6427 is a quad 4
th
-order Butterworth lowpass
reconstruction filter plus quad video amplifier optimized
for minimum overshoot and flat group delay. Each filter
channel has a two-input multiplexer that switches between
two groups of quad video signals. Applications driving
SCART and EVC cables are supported for composite,
component, and RGB video.
1V
P-P
input signals from DACs are AC coupled into the
ML6427 where they are DC restored. Outputs are AC
coupled and drive 2V
P-P
into a 150W load. The ML6427
can provide DC coupled outputs for certain applications.
A fifth unfiltered channel is provided to support an
additional analog composite video input. A swapping
multiplexer between the two composite channels allows
the distribution amplifiers to output from either input.
Several ML6427s can be arranged in a master-slave
configuration where an external sync can be used for CV
and RGB outputs.
FEATURES
s
Cable drivers for Peritel (SCART), Enhanced Video
Connector (EVC), and standard video connectors, 75W
cable drivers for CV, S-video, and RGB
7.1MHz CV, RGB, and S-video, NTSC or PAL filters
with mux inputs and output channel mux
Quad reconstruction filter or dual anti-aliasing filter
43dB stopband attenuation at 27MHz
1dB flatness up to 4.8MHz
12ns group delay flatness up to 10MHz
0.4% differential gain, 0.4º differential phase on all
channels
0.4% total harmonic distortion on all channels
Master-slave configuration allows up to 8 multiplexed,
filtered output signals
s
s
s
s
s
s
s
s
BLOCK DIAGRAM
SYNCIN
2
SYNC
TIMER
17
VCCORGB
UNFILTERED CHANNEL
22
VCCOCV
6
VCC
14
SWAP CVU
13
SWAP CVF
SYNCIN
23
SYNCOUT
24
3
4
CVINFA/Y2*
CVINFB/Y3*
RINA/Y4
RINB/Y5
MUX
MUX
TRANSCONDUCTANCE
ERROR AMP
+
–
0.5V
×2
SWAP
MUX
SYNC
TIMER
REQUIRED
SYNC STRIP
TRANSCONDUCTANCE
ERROR AMP
+
–
CVOUT1/YOUTA
21
4th-ORDER
FILTER
×2
CVOUT/YOUTB
20
7
8
0.5V
4th-ORDER
FILTER
×2
TRANSCONDUCTANCE
ERROR AMP
ROUT/YOUTC
18
+
–
9
GINA/Y6
MUX
TRANSCONDUCTANCE
ERROR AMP
0.5V
4th-ORDER
FILTER
×2
GOUT/YOUTD
16
GINB/Y2
10
BINA/C1
11
BINB/C2
12
A/B MUX
1
+
–
0.5V
4th-ORDER
FILTER
×2
BOUT/COUT
15
MUX
TRANSCONDUCTANCE
ERROR AMP
+
–
0.75V
GNDO
19
GND
5
*CAN ALSO INPUT SYNC ON GREEN SIGNALS
1
MICRO-LINEAR [ MICRO LINEAR CORPORATION ]
