June 1999
PRELIMINARY
ML6423*
Dual S-Video Lowpass Filter with
Phase and Sinx/x Equalization
GENERAL DESCRIPTION
The ML6423 monolithic BiCMOS 6th-order filter provides
a two-channel fixed frequency lowpass filtering for video
applications. This dual phase equalized filter with sinx/x
correction is designed for reconstruction filtering at the
output of a Video DAC. A composite sum output
eliminates the need for a third DAC.
Cutoff frequencies are either 5.5MHz or 9.6MHz. Each
channel incorporates a 6th-order lowpass filter, a first
order allpass filter, a gain boost circuit, and a 75W coax
cable driver. A control pin (RANGE) is provided to allow
the inputs to swing from 0 to 1V, or 0.5 to 1.5V, by
providing a 0.5V offset to the input.
The 2X gain filters are powered from a single 5V supply,
and can drive 1V
P-P
into 75W (0.5V to 1.5V), or 2V
P-P
into
150W (0.5V to 2.5V) with the internal coax drivers.
FEATURES
s
5.5 or 9.6MHz bandwidth with 6dB gain
s
>40dB stopband rejection
s
No external components or clocks
s
±10% frequency accuracy over maximum supply
and temperature variation
s
<2% differential gain, <2° differential phase
s
<20ns group delay variation
s
5V ±10% operation
s
Composite (sum) output
s
High sink current for AC coupled loads, ML6423-5
* This Product Is End Of Life As Of August 1, 2000
BLOCK DIAGRAM
10
V
CC
B
7
V
CC
C
4
V
CC
13
V
CC
A
V
IN
A (Y)
16
2kΩ
I
BIAS
2kΩ
BUF
V
OUT
A (Y)
LOWPASS
FILTER A
ALLPASS
FILTER
SINX/X
EQUALIZER
2X
BUF
3.43kΩ
12
15 RANGE
∑
2X
BUF
V
OUT
B (CV)
8
3.43kΩ
V
IN
C (C)
1
2kΩ
I
BIAS
2kΩ
GND
2
BUF
LOWPASS
FILTER C
ALLPASS
FILTER
SINX/X
EQUALIZER
2X
BUF
V
OUT
C (C)
6
3.43kΩ
GNDA
14
GNDC
3
GNDB
9
Filter A
Filter C
ML6423-1
5.50MHz
5.50MHz
ML6423-2
9.6MHz
9.6MHz
ML6423-5
9.6MHz
9.6MHz
1
MICRO-LINEAR [ MICRO LINEAR CORPORATION ]
