LTC1069-6_15 Datasheet, PDF (1/10 Pages) Linear Technology – Single Supply, Very Low Power, Elliptic Lowpass Filter

LTC1069-6
Single Supply, Very Low
Power, Elliptic Lowpass Filter
FEATURES
n _{8th Order Elliptic Filter in SO-8 Package}
n _{Single 3V Operation: Supply Current: 1mA (Typ)}
f_CUTOFF: 14kHz (Max) S/N Ratio: 72dB
n _{Single 5V Operation: Supply Current: 1.2mA (Typ)}
f_CUTOFF: 20kHz (Max) S/N Ratio: 79dB
n _{± 0.1dB Passband Ripple Up to 0.9fCUTOFF (Typ)}
n _{42dB Attenuation at 1.3fCUTOFF}
n _{66dB Attenuation at 2.0fCUTOFF}
n _{70dB Attenuation at 2.1fCUTOFF}
n _{Wide Dynamic Range, 75dB or More (S/N + THD),}
Under Single 5V Operation
n _{Wideband Noise: 120µVRMS}
n _{Clock-to-fCUTOFF Ratio: 50:1}
n _{Internal Sample Rate: 100:1}
APPLICATIONS
n _{Handheld Instruments}
n _{Telecommunication Filters}
n _{Antialiasing Filters}
n _{Smoothing Filters}
n _Audio
n _Multimedia
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
DESCRIPTION
The LTC^®1069-6 is a monolithic low power, 8th order lowpass
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.
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.
The typical passband ripple is ± 0.1dB up to 0.9f_CUTOFF.
The gain at f_CUTOFF is –0.7dB. The transition band of the
LTC1069-6 features progressive attenuation reaching
42dB at 1.3f_CUTOFF and 70dB at 2.1f_CUTOFF. The maximum
stopband attenuation is 72dB.
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).
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 0.4V_RMS to 1.4V_RMS, the Signal-to-
(Noise + THD) ratio is ≥70dB. The wideband noise of the
LTC1069-6 is 125μV_RMS.
Other filter responses with higher speed can be obtained.
Please contact LTC Marketing for details.
The LTC1069-6 is available in an 8-pin SO package.
TYPICAL APPLICATION
Single 3V Supply 10kHz Elliptic Lowpass Filter
0.47μF
3V
0.1μF
AGND
V_OUT
V⁺
V^–
LTC1069-6
NC
NC
V_IN
CLK
f_CLK = 500kHz
1069-6 TA01
Frequency Response
10
V_IN = 500mV_RMS
0
–10
–20
–30
– 40
– 50
– 60
–70
– 80
5
10
15
20
FREQUENCY (kHz)
25
1069-6 TA02
10696fa
1