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LTC1164-8

Ultraselective, Low Power

8th Order Elliptic Bandpass Filter

with Adjustable Gain

FEATURES

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Ultraselectivity

(50dB Attenuation at

±4% of Center Frequency)

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Adjustable Passband Gain

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Noise Independent of Gain

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Filter Noise: 270

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The LTC

elliptic bandpass filter. The passband of the LTC1164-8 is

tuned with an external clock and the clock-to-center fre-

quency ratio is 100:1. The – 3dB pass bandwidth is typi-

cally 1% of the filter center frequency. The stopband

attenuation of the LTC1164-8 is greater than 50dB. The

lower and upper stopband frequencies are less than

0.96 • center frequency and greater than 1.04 • center

frequency, respectively.

The LTC1164-8 requires an external op amp and two

external resistors (see the circuit below). The filter’s gain

increase the filter’s wideband noise. The 270

wideband noise of the LTC1164-8 is independent of the

filter’s center frequency.

The LTC1164-8 is available in a 14-pin PDIP or a 16-pin

surface mount SO Wide package.

Frequency Response

Ultranarrow 1kHz Bandpass Filter with Gain = 10

LTC1164-8

–5V

–5V

5V

2

3

4

6

7

LTC1164-8 • TA01

5V

34k

100kHz

SHORT CONNECTION UNDER IC AND

SHIELDED BY A GROUND PLANE

1

2

3

4

5

6

7

14

13

12

11

10

9

8

61.9k

200pF

–

+

LT

FREQUENCY (kHz)

0.90

30

20

10

0

–10

–20

–30

–40

–50

–60

–70

1.10

1164-8 TA02

0.95

1.00

1.05

1.15

50dB

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Asynchronous Narrowband Signal Detectors

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Low Frequency Asynchronous Demodulators

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Handheld Spectrum Analyzers

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In-Band Tone Signaling Detectors

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