LTC1069-6
Single Supply, Very Low
Power, Elliptic Lowpass Filter
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FEATURES
DESCRIPTION
The LTC®1069-6 is a monolithic low power, 8th order low-
pass filter optimized for single 3V or single 5V supply
operation. The LTC1069-6 typically consumes 1mA under
single 3V supply operation and 1.2mA under 5V operation.
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8th Order Elliptic Filter in SO-8 Package
Single 3V Operation: Supply Current: 1mA (Typ)
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fCUTOFF: 14kHz (Max)
S/N Ratio: 72dB
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Single 5V Operation: Supply Current: 1.2mA (Typ)
The cutoff frequency of the LTC1069-6 is clock tunable and it
is equal to the clock frequency divided by 50. The input signal
is sampled twice per clock cycle to lower the risk of aliasing.
fCUTOFF: 20kHz (Max)
S/N Ratio: 79dB
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±0.1dB Passband Ripple Up to 0.9fCUTOFF (Typ)
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The typical passband ripple is ±0.1dB up to 0.9fCUTOFF
.
42dB Attenuation at 1.3fCUTOFF
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The gain at fCUTOFF is –0.7dB. The transition band of the
LTC1069-6featuresprogressiveattenuationreaching42dB
at 1.3fCUTOFF and 70dB at 2.1fCUTOFF. The maximum
stopband attenuation is 72dB.
66dB Attenuation at 2.0fCUTOFF
70dB Attenuation at 2.1fCUTOFF
Wide Dynamic Range, 75dB or More (S/N + THD),
Under Single 5V Operation
Wideband Noise: 120µVRMS
Clock-to-fCUTOFF Ratio: 50:1
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The LTC1069-6 can be clock tuned for cutoff frequencies
up to 20kHz (single 5V supply) and for cutoff frequencies
up to 14kHz (single 3V supply).
Internal Sample Rate: 100:1
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The low power feature of the LTC1069-6 does not penalize
the device’s dynamic range. With single 5V supply and an
input range of 0.4VRMS to 1.4VRMS, the Signal-to-(Noise
+ THD) ratio is ≥70dB. The wideband noise of the
APPLICATIONS
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Handheld Instruments
Telecommunication Filters
Antialiasing Filters
Smoothing Filters
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LTC1069-6 is 125µVRMS
.
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Other filter responses with higher speed can be obtained.
Please contact LTC Marketing for details.
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Audio
Multimedia
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The LTC1069-6 is available in an 8-pin SO package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATION
Frequency Response
10
V
= 500mV
RMS
IN
Single 3V Supply 10kHz Elliptic Lowpass Filter
0
–10
–20
–30
–40
–50
–60
–70
AGND
V
OUT
3V
+
–
0.47µF
V
V
0.1µF
LTC1069-6
NC
NC
f
= 500kHz
V
CLK
CLK
IN
1069-6 TA01
–80
5
10
20
FREQUENCY (kHz)
25
15
1069-6 TA02
1