LTC1064-3

1

10643fa

FEATURES

APPLICATIO S

DESCRIPTIO

TYPICAL APPLICATIO

■

Antialiasing Filters

■

Smoothing Filters

■

Tracking High Frequency Lowpass Filters

■

8th Order Filter in a 14-Pin Package

■

95kHz Maximum Corner Frequency

■

No External Components

■

75:1, 150:1 and 120:1 Clock to Cutoff Frequency

Ratio

■

60µVRMS Total Wideband Noise

■

0.03% THD or Better

■

Operates from ±2.37V to ±8V Power Supplies

■

Low Total Output DC Offset

Low Noise, High Frequency,

8th Order Linear Phase Lowpass Filter

The LTC

®1064-3 is a monolithic 8th order lowpass Bessel

filter, which provides a linear phase response over its

entire passband. An external TTL or CMOS clock pro-

grams the filter’s cutoff frequency. The clock to cutoff

frequency ratio is 75:1 (Pin 10 at V+) or 150:1 (Pin 10 at

V–) or 120:1 (Pin 10 at GND). The maximum cutoff

frequency is 95kHz. No external components are needed.

The LTC1064-3 features low wideband noise and low

harmonic distortion even for input voltages up to 3VRMS.

In fact the LTC1064-3 overall performance competes with

equivalent multiple op amp RC active realizations. The

LTC1064-3 is available in a 14-pin DIP or 16-pin surface

mounted SOL package. The LTC1064-3 is fabricated using

LTC’s enhanced analog CMOS Si-gate process.

The LTC1064-3 is pin compatible with the LTC1064-1,

LTC1064-2 and LTC1064-4.

8th Order Clock Sweepable Lowpass Bessel Filter

Measured Frequency Response

LTC1064-3

1

2

3

4

5

6

7

14

13

12

11

10

9

8

OUT C

NC

V–

fCLK

75/150

VOUT

NC

V+

NC

VIN

AGND

AGND

NC

INV A

1064 TA01a

NOTE: THE POWER SUPPLIES SHOULD BE BYPASSED BY A 0.1µF

OR LARGER CAPACITOR CLOSE TO THE PACKAGE. THE CONNECTI0N

BETWEEN PIN 7 AND PIN 14 SHOULD BE MADE UNDER THE IC PACKAGE.

CLOCK = 7MHz

V+

–8V

8V

0.1µF

0.1µF

VIN

VOUT

FREQUENCY (kHz)

10

0

–15

–30

–45

–60

–75

–90

–105

1064-3 TA01b

100

1000

VS = ±7.5V, fCLK = 7MHz, PIN 10 TO V

+,

f–3dB = 95kHz, GROUP DELAY = 6µs

, LTC and LT are registered trademarks of Linear Technology Corporation.