ML6421 Datasheet, PDF (1/13 Pages) Micro Linear Corporation – Triple Phase and Sinx/x Equalized, Low-Pass Video Filter

September 1999
ML6421*
Triple Phase and Sinx/x Equalized,
Low-Pass Video Filter
GENERAL DESCRIPTION
The ML6421 monolithic BiCMOS 6th-order filter provides
fixed frequency low pass filtering for video applications.
This triple phase-equalized filter with Sinx/x correction is
designed for reconstruction filtering at the output of a
Video DAC.
Cut-off frequencies are either 5.5, 8.0, or 3.0MHz. Each
channel incorporates a 6th-order lowpass filter, a first
order all-pass filter, a gain boost circuit, and a 75Ω 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 unity gain filters are powered from a single 5V supply,
and can drive 1V_P-P over 75Ω (0.5V to 1.5V), or 2V_P-P
over 150Ω (0.5V to 2.5V) with the internal coax drivers.
FEATURES
s 5.5, 8.0, 9.3, or 3.0MHz bandwidth
s 1x or 2x gain
s 6th-order filter with phase and amplitude equalizer
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 <25ns group delay variation
s Drives 1V_P-P into 75Ω, or 2V_P-P into 150Ω
s 5V ±10% operation
BLOCK DIAGRAM
VINA 15
3kΩ
1kΩ
VINB 16
3kΩ
1kΩ
VINC 2
3kΩ
RANGE 14
1kΩ
VCCB
8
VCCC
VCC
6
5
VCCA
11
BUF
IBIAS
LOW PASS
FILTER A
ALL
PASS
FILTER
SINX/X
EQUALIZER
1X/2X
BUF
*Some Packages Are Obsolete
10 VOUTA
3.33kΩ
BUF
IBIAS
LOW PASS
FILTER B
ALL
PASS
FILTER
SINX/X
EQUALIZER
1X/2X
BUF
9 VOUTB
3.33kΩ
BUF
IBIAS
LOW PASS
FILTER C
ALL
PASS
FILTER
SINX/X
EQUALIZER
1X/2X
BUF
7 VOUTC
3.33kΩ
12
GND
13
GNDA
4
GNDC
1
GNDB
3
GND
FilterA
Filter B
Filter C
ML6221-1
5.5MHz
5.5MHz
5.5MHz
1x GAIN
ML6421-3 ML6421-4
8.0MHz
8.0MHz
8.0MHz
8.0MHz
3.0MHz
3.0MHz
2x GAIN
ML6421-5 ML6421-7
5.5MHz
5.5MHz
5.5MHz
9.3MHz
9.3MHz
9.3MHz
Triple Input/Anti-aliasing Video Filter
1