Micro Linear Corporation ML6421CS-4, ML6421CS-5, ML6421CS-7, ML6421CS-1, ML6421CS-3 Datasheet

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

FEATURES

■ 5.5, 8.0, 9.3, or 3.0MHz bandwidth

■ 1x or 2x gain

■ 6th-order filter with phase and amplitude equalizer

■ >40dB stopband rejection

■ No external components or clocks

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

■ ±10% frequency accuracy over maximum supply

and temperature variation

■ <2% differential gain <2° differential phase

providing a 0.5V offset to the input.

■ <25ns group delay variation

The unity gain filters are powered from a single 5V supply,
and can drive 1V

over 75Ω (0.5V to 1.5V), or 2V

P-P

P-P

over 150Ω (0.5V to 2.5V) with the internal coax drivers.

BLOCK DIAGRAM *Some Packages Are Obsolete

15

V

A

IN

3kΩ

1kΩ

I

BIAS

BUF

V

B

CC

8

LOW PASS

FILTER A

C

V

CC

6

■ Drives 1V

P-P

■ 5V ±10% operation

V

CC

5

ALL

PASS

FILTER

SINX/X

EQUALIZER

into 75Ω, or 2V

V

A

CC

11

1X/2X
BUF

3.33kΩ

into 150Ω

P-P

10

V

OUT

A

V

IN

V

IN

RANGE

B

16

3kΩ

1kΩ

2

C

3kΩ

14

1kΩ

I

I

BIAS

BIAS

BUF

BUF

12

GND

LOW PASS

FILTER B

LOW PASS

FILTER C

13

GNDA

ALL

PASS

FILTER

ALL

PASS

FILTER

4

GNDC

SINX/X

EQUALIZER

SINX/X

EQUALIZER

1

GNDB

1X/2X
BUF

1X/2X
BUF

9

3.33kΩ

7

3.33kΩ

3

GND

1x GAIN 2x GAIN

ML6221-1 ML6421-3 ML6421-4 ML6421-5 ML6421-7

FilterA 5.5MHz 8.0MHz 8.0MHz 5.5MHz 9.3MHz
Filter B 5.5MHz 8.0MHz 3.0MHz 5.5MHz 9.3MHz
Filter C 5.5MHz 8.0MHz 3.0MHz 5.5MHz 9.3MHz

Triple Input/Anti-aliasing Video Filter

V

B

OUT

C

V

OUT

1

ML6421

PIN CONFIGURATION

PIN DESCRIPTION

ML6421

16-Pin Wide SOIC (S16W)

CC

1
2
3
4
5
6
7

C

8

TOP VIEW

GNDB

VINC

GND

GNDC

VCCC

V

OUT

VCCB

V

16

VINB

15

VINB

14

RANGE

13

GNDA

12

GND

11

VCCA

10

V

A

OUT

9

V

A

OUT

PIN NAME FUNCTION

1 GNDB Ground pin for filter B.
2VINC Signal input to filter C. Input

impedance is 4kΩ.
3 G N D Po wer and logic ground.
4 GNDC Ground pin for filter C.
5V

CC

Positive supply.
6VCCC Power supply for filter C.
7V

C Output of filter C. Drive is 1V

OUT

75Ω (0.5V to 1.5V), or 2V

P-P

P-P

into

into

150Ω (0.5V to 2.5V).
8VCCB Power supply for filter B: 4.5V to 5.5V.
9V

B Output of filter B. Drive is 1V

OUT

75Ω (0.5V to 1.5V), or 2V

P-P

P-P

into

into

150Ω (0.5V to 2.5V).

10 V

A Output of filter A. Drive is 1V

OUT

75Ω (0.5V to 1.5V), or 2V

P-P

P-P

into

into

150Ω (0.5V to 2.5V).

PIN NAME FUNCTION

11 VCCA Power supply for filter A.
1 2 GN D Power and logic ground.
1 3 GN DA Ground pin for filter A.
14 RANGE Input signal range select.

For –1 to –4; when RANGE is low (0),
the input signal range is 0.5V to 2.5V,
with an output range of 0.5V to 2.5V.
When RANGE is high (1), the input
signal range is 0V to 2V, with an
output range of 0.5V to 2.5V.
For –5 to –7; when RANGE is low (0),
the input signal range is 0.5V to 1.5V,
with an output range of 0.5V to 2.5V.
When RANGE is high (1), the input
signal range is 0V to 1V, with an
output range of 0.5V to 2.5V.

15 VINA Signal input to filter A. Input

impedance is 4kΩ.

16 VINB Signal input to filter B. Input

impedance is 4kΩ.

2

ABSOLUTE MAXIMUM RATINGS

ML6421

Absolute maximum ratings are those values beyond which
the device could be permanently damaged. Absolute
maximum ratings are stress ratings only and functional

Package Dissipation at TA = 25°C .............................. 1W

Lead Temperature (Soldering 10 sec) ......................260°C

Thermal Resistance (θJA)..................................... 65°C/W

device operation is not implied.

Supply Voltage (VCC)....................... –5.5MHz0.3 to +7V

GND .................................................. –0.3 to VCC +0.3V

OPERATING CONDITIONS

Logic Inputs ........................................–0.3 to VCC +0.3V

Input Current per Pin ............................................±25mA

Storage Temper ature.................................. –65° to 150°C

TSupply V oltage ...............................................5V ± 10%

Temperature Range ................................ 0°C < to < 70°C

ELECTRICAL CHARACTERISTICS

Unless otherwise specified VCC = 5V ± 10% and TA = T
V

= 1V

OUT

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
GENERAL

R

IN

DR/R

IN

I

BIAS

for 75Ω Load (Note 1)

P-P

Input Impedance 3 4 5 kΩ
Input R Matching ±2 %
Input Current VIN = 0.5V, ML6421(–1 to –4) –80 µA

range = low ML6421(–5 to –7) 45 µA
VIN = 0.0V, ML6421(–1 to –4) –125 µA

MIN

to T

, RL =75Ω or 150Ω, V

MAX

OUT

= 2V

for 150Ω Load and

P-P

range = high ML6421(–5 to –7) –210 µA

Small Signal Gain VIN = 100mV

at 100kHz ML6421(–5 to –7) 5.5 6 6.5 dB

Differential Gain VIN = 1.1V to 2.5V ML6421(–1 to –4) 1 %

at 3.58 & 4.43 MHz
V

= 0.8V to 1.5V ML6421(–5 to –7) 1 %

IN

at 3.58 & 4.43 MHz

Differential Phase V

V

Input Range Range = 0 ML6421(–1 to –4) 0.5 2.5 V

IN

Peak Overshoot 2T, 0.7V
Crosstalk Rejection fIN = 3.58, ML6421(–1 to –4) 50 dB

= 1.1V to 2.5V ML6421(–1 to –4) 1 deg

IN

at 3.58 & 4.43 MHz
VIN = 0.8V to 1.5V ML6421(–5 to –7) 1 deg

at 3.58 & 4.43 MHz

Range = 1 ML6421(–1 to –4) 0.0 2.0 V
ML6421(-5 to -8) 0.0 1 V

fIN = 4.43MHz ML6421(–5 to –7) 45 dB
(Note 6)

P-P

pulse 2.0 %

P-P

ML6421(–1 to –4) –0.5 0 0.5 dB

ML6421(–5 to –7) 0. 5 1.5 V

Channel to Channel fIN = 100kHz ±10 ns
Group Delay Matching
(fC = 5.5MHz)

Channel to Channel fIN = 100kHz ±2 %
Group Matching

3

ML6421

ELECTRICAL CHARACTERISTICS (Continued)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
GENERAL (Continued)

Output Current RL = 0 (short circuit) 175 mA

C

L

5.50MHZ FILTER (ML6421-1, -5)

8.0MHZ FILTER

Load Capacitance 35 pF

Composite Chroma fC = 5.5MHz ML6421(–1 to –4) ±15 ns

/Luma delay ML6421(–5 to –7) ± 15 n s

Bandwidth –0.75dB (Note 5) ML6421(–1 to –4) 4.95 5.50 6.05 MHz
(monotonic passband) –0.55dB (Note 5) ML6421(–5 to –7) 4.95 5.50 6.05 MH z
Subcarrier Frequency Gain fIN = 3.58MHz ML6421(–1 to –4) –0.3 0.2 0.7 dB

ML6421-1 ML6421(–5 to –7) –0.9 1.4 1.9 dB

Attenuation fIN = 10MHz ML6421(–1 to –4) 16 1 8 dB

Output Noise BW = 30MHz (Note 6) 1000 µV
Group Delay 145 ns

fC = 8.0MHz/9.3MHz ±8 ns

fIN = 4.43MHz ML6421(–1 to –4) –0.35 0.1 0.65 dB

ML6421(–5 to –7) 1. 1 1.6 2 .1 dB

ML6421(–5 to –7) 2 0 25 dB

fIN = 50MHz 40 45 dB

RMS

Bandwidth –3dB (Note 5) 7.2 8 8.8 MHz
(monotonic passband)

Subcarrier Frequency Gain fIN = 3.58MHz –0.25 0.25 0.75 dB
ML6421-3 or ML6421 fIN = 4.43MHz –0.11 0.39 0.89 dB

4/ML6421-7

Attenuation fIN = 17MHz 20 25 dB

Output Noise BW = 30MHz (Note 6) 1000 µV
Group Delay 120 ns

9.3MHZ FILTER

Bandwidth –2dB (Note 5) 8.4 9.3 10.2 MHz
(monotonic passband)

Subcarrier Frequency Gain fIN = 3.58MHz –0.01 0.4 0.9 dB
ML6421-3 or ML6421 fIN = 4.43MHz –0.1 0.6 1.1 dB

4/ML6421-7

Attenuation fIN = 17MHz 20 25 dB

Output Noise BW = 30MHz (Note 6) 1000 µV
Group Delay 120 ns

fIN = 85MHz 40 42 dB

RMS

fIN = 85MHz 40 42 dB

RMS

4