LTC1164-7_1 Datasheet, PDF (1/16 Pages) Linear Technology – Low Power, Linear Phase 8th Order Lowpass Filter

LTC1164-7
Low Power, Linear Phase
8th Order Lowpass Filter
FEATURES
■ _{Better Than Bessel Roll-Off}
■ _{fCUTOFF up to 20kHz, Single 5V Supply}
■ _{ISUPPLY = 2.5mA (Typ), Single 5V Supply}
■ _{75dB THD + Noise with Single 5V Supply}
■ _{Phase and Group Delay Response Fully Tested}
■ _{Transient Response with No Ringing}
■ _{Wide Dynamic Range}
■ _{No External Components Needed}
■ _{Available in 14-Lead N and 16-Lead SW Packages}
U
APPLICATIO S
■ _{Data Communication Filters}
■ _{Time Delay Networks}
■ _{Phase Matched Filters}
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
DESCRIPTIO
The LTC1164-7 is a low power, clock-tunable monolithic
8th order lowpass filter with linear passband phase and
flat group delay. The amplitude response approximates a
maximally flat passband and exhibits steeper roll-off than
an equivalent 8th order Bessel filter. For instance, at twice
the cutoff frequency the filter attains 34dB attenuation
(vs12dB for Bessel), while at three times the cutoff fre-
quency the filter attains 68dB attenuation (vs 30dB for
Bessel). The cutoff frequency of the LTC1164-7 is tuned
via an external TTL or CMOS clock.
Low power is achieved without sacrificing dynamic range.
With single 5V supply, the S/N + THD is up to 75dB.
Optimum 91dB S/N is obtained with ±7.5V supplies.
The clock-to-cutoff frequency ratio of the LTC1164-7 can
be set to 50:1 (Pin 10 to V⁺) or 100:1 (Pin 10 to V ^–).
When the filter operates at the clock-to-cutoff frequency
ratio of 50:1, the input is double-sampled to lower the risk
of aliasing.
The LTC1164-7 is pin-compatible with the LTC1064-X
series and LTC1264-7.
TYPICAL APPLICATIO
10kHz Linear Phase Lowpass Filter
1
14
V_IN
2
3
13
12
–5V
5V
4 _LTC1164-7 11
CLK = 500kHz
5
10
5V
6
9
V_OUT
7
8
NOTE: THE POWER SUPPLIES SHOULD BE BYPASSED
BY A 0.1µF CAPACITOR CLOSE TO THE PACKAGE
AND ANY PRINTED CIRCUIT BOARD ASSEMBLY
SHOULD MAINTAIN A DISTANCE OF AT LEAST 0.2
INCHES BETWEEN ANY OUTPUT OR INPUT PIN AND
THE f_CLK LINE.
1164-7 TA01
Frequency Response
0
– 10
– 20
– 30
– 40
– 50
– 60
– 70
– 80
1
GAIN
DELAY
10
FREQUENCY (kHz)
150
140
130
120
110
100
90
80
70
100
1164-7 TA02
11647fb
1