LTC1164-6
Low Power 8th Order
Pin Selectable Elliptic or
Linear Phase Lowpass Filter
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FEATURES
DESCRIPTIO
The LTC®1164-6 is a monolithic 8th order elliptic lowpass
filter featuring clock-tunable cutoff frequency and low
power supply current. Low power operation is achieved
without compromising noise or distortion performance.
At ±5V supplies the LTC1164-6 uses only 4mA supply
■
8th Order Pin Selectable Elliptic or Bessel Filter
■
4mA Supply Current with ±5V Supplies
■
64dB Attenuation at 1.44 fCUTOFF (Elliptic Response)
■
fCUTOFF Up to 30kHz (50:1 fCLK to fCUTOFF Ratio)
■
110µVRMS Wideband Noise with ±5V Supplies
■
current while keeping wideband noise below 110µVRMS
.
Operates at Single 5V Supply with 1VRMS
With a single 5V supply, the LTC1164-6 can provide up to
10kHz cutoff frequency and 80dB signal-to-noise ratio
while consuming only 2.5mA.
Input Range
■
Operates Up to ±8V Supplies
■
TTL/CMOS Compatible Clock Input
■
No External Components
The LTC1164-6 provides an elliptic lowpass rolloff with
stopband attenuation of 64dB at 1.44 fCUTOFF and an fCLK
■
Available in 14-Pin Dip and 16-Pin SO Wide Packages
-
to-fCUTOFF ratioof100:1(Pin10toV–).Foraratioof100:1,
fCUTOFF can be clock-tuned up to 10kHz. For a fCLK-to-
fCUTOFF ratio of 50:1 (Pin 10 to V+), the LTC1164-6
provides an elliptic lowpass filter with fCUTOFF frequencies
up to 20kHz. When Pin 10 is connected to ground, the
LTC1164-6 approximates an 8th order linear phase re-
sponse with 65dB attenuation at 4.5 f–3dB and fCLK/f–3dB
ratio of 160:1. The LTC1164-6 is pin compatible with the
LTC1064-1.
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APPLICATIO S
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Antialiasing Filters
■
Battery-Operated Instruments
■
Telecommunication Filters
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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TYPICAL APPLICATIO
10kHz Anti-Aliasing Elliptic Filter
Frequency Response
1
2
3
4
5
6
7
14
13
12
11
10
9
NC
0
–10
–20
–30
–40
–50
–60
–70
–80
V
IN
NC
–8V
LTC1164-6
CLK = 1MHz
8V
–8V
V
OUT
8
1164-6 TA01
WIDEBAND NOISE = 115µV
RMS
NOTE: THE CONNECTION FROM PIN 7 TO PIN 14 SHOULD BE MADE
UNDER THE PACKAGE. THE POWER SUPPLIES SHOULD BE BYPASSED
BY A 0.1µF CAPACITOR AS CLOSE TO THE PACKAGE AS POSSIBLE.
1
10
100
FREQUENCY (kHz)
1164-6 TA02
11646fa
1