LTC1064-2_09 Datasheet, PDF (1/12 Pages) Linear Technology – Low Noise, High Frequency, 8th Order Butterworth Lowpass Filter

LTC1064-2
Low Noise, High Frequency,
8th Order Butterworth Lowpass Filter
FEATURES
■ _{8th Order Filter in a 14-Pin Package}
■ _{140kHz Maximum Corner Frequency}
■ _{No External Components}
■ _{50:1 and 100:1 Clock to Cutoff Frequency Ratio}
■ _{80µVRMS Total Wideband Noise}
■ _{0.03% THD or Better}
■ _{Operates from ±2.37V to ±8V Power Supplies}
U
APPLICATIO S
■ _{Antialiasing Filters}
■ _{Smoothing Filters}
■ _{Tracking High Frequency Lowpass Filters}
DESCRIPTIO
The LTC^®1064-2 is a monolithic 8th order lowpass
Butterworth filter, which provides a maximally flat pass-
band. The attenuation slope is –48dB/octave and the
maximum attenuation is in excess of 80db. An external
TTL or CMOS clock programs the filter’s cutoff frequency.
The clock to cutoff frequency ratio is 100:1 (Pin 10 at
V^–) or 50:1 (Pin 10 at V ⁺). The maximum cutoff frequency
is 140kHz. No external components are needed.
The LTC1064-2 features low wideband noise and low
harmonic distortion even for input voltages up to 3V_RMS.
In fact the LTC1064-2 overall performance competes with
equivalent multiple op amp RC active realizations. The
LTC1064-2 is available in a 14-pin DIP or 16-pin surface
mounted SW package. The LTC1064-2 is fabricated using
LTC’s enhanced analog CMOS Si-gate process.
The LTC1064-2 is pin compatible with the LTC1064-1.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
8th Order Clock Sweepable
Lowpass Butterworth Filter
1
NC
14
OUT C
2 ^LTC1064-2 13
V_IN
NC
3
AGND
V^–
12
–8V
8V ⁴ V⁺
f_CLK ¹¹ CLOCK = 5MHz
5
10
AGND 50/100
6
NC
9
V_OUT
7
R_IN A
8
NC
1064 TA01a
NOTE: THE POWER SUPPLIES SHOULD BE BYPASSED BY A 0.1µF
CAPACITOR CLOSE TO THE PACKAGE. THE NC PINS 1, 6, 8,
AND 13 SHOULD BE PREFERABLY GROUNDED.
Measured Frequency Response
0
V_S = ±7.5V
–15
–30
–45
–60
–75
–90
–105
0 100 200 300 400 500 600 700
FREQUENCY (kHz)
1064-2 TA01b
10642fa
1