LTC1064-3_09 Datasheet, PDF (1/12 Pages) Linear Technology – Low Noise, High Frequency, 8th Order Linear Phase Lowpass Filter

LTC1064-3
Low Noise, High Frequency,
8th Order Linear Phase Lowpass Filter
FEATURES
■ _{8th Order Filter in a 14-Pin Package}
■ _{95kHz Maximum Corner Frequency}
■ _{No External Components}
■ _{75:1, 150:1 and 120:1 Clock to Cutoff Frequency}
Ratio
■ _{60µVRMS Total Wideband Noise}
■ _{0.03% THD or Better}
■ _{Operates from ±2.37V to ±8V Power Supplies}
■ _{Low Total Output DC Offset}
U
APPLICATIO S
■ _{Antialiasing Filters}
■ _{Smoothing Filters}
■ _{Tracking High Frequency Lowpass Filters}
DESCRIPTIO
The LTC^®1064-3 is a monolithic 8th order lowpass Bessel
filter, which provides a linear phase response over its
entire passband. An external TTL or CMOS clock pro-
grams the filter’s cutoff frequency. The clock to cutoff
frequency ratio is 75:1 (Pin 10 at V⁺) or 150:1 (Pin 10 at
V^–) or 120:1 (Pin 10 at GND). The maximum cutoff
frequency is 95kHz. No external components are needed.
The LTC1064-3 features low wideband noise and low
harmonic distortion even for input voltages up to 3V_RMS.
In fact the LTC1064-3 overall performance competes with
equivalent multiple op amp RC active realizations. The
LTC1064-3 is available in a 14-pin DIP or 16-pin surface
mounted SOL package. The LTC1064-3 is fabricated using
LTC’s enhanced analog CMOS Si-gate process.
The LTC1064-3 is pin compatible with the LTC1064-1,
LTC1064-2 and LTC1064-4.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
8th Order Clock Sweepable Lowpass Bessel Filter
V_IN
8V
0.1µF
1
NC
14
OUT C
2
V_IN
13
NC
3
LTC1064-3
AGND
V^–
12
4 _V+
5
AGND
11
f_CLK CLOCK = 7MHz
75/150 ¹⁰ V⁺
6
NC
7
INV A
9
V_OUT
8
NC
–8V
0.1µF
V_OUT
1064 TA01a
NOTE: THE POWER SUPPLIES SHOULD BE BYPASSED BY A 0.1µF
OR LARGER CAPACITOR CLOSE TO THE PACKAGE. THE CONNECTI0N
BETWEEN PIN 7 AND PIN 14 SHOULD BE MADE UNDER THE IC PACKAGE.
Measured Frequency Response
0
–15
–30
–45
–60
–75
–90 _{VS = ±7.5V, fCLK = 7MHz, PIN 10 TO V}⁺_,
f_–3dB = 95kHz, GROUP DELAY = 6µs
–105
10
100
FREQUENCY (kHz)
1000
1064-3 TA01b
10643fa
1