
25 Locust St, Haverhill, Massachusetts 01830  Tel: 800/252-7074, 978/374-0761  FAX: 978/521-1839
e-mail: sales@freqdev.com    Web Address: http://www.freqdev.com
1.0 Hz to 102.4 kHz
8-Bit Programmable
D824 Series
2" x 2"
Differential Input
4-Pole Filters
Description
The D824 Series are digitally programmable low
pass and high pass active filters with differential
input that are tunable over a 256:1 frequency range.
D824 filters are available with any one of five
standard factory-set tuning ranges up to 102.4 kHz.
These units contain 8 CMOS logic inputs .
All D824 Series models are convenient, low profile,
easy to use fully finished filters which require no ex-
ternal components or adjustments. They feature low
harmonic distortion, and near theoretical phase and
amplitude characteristics.  D824 filters operate from
non-critical ± 12 to ± 18 Vdc power supplies, have a
10 k
W
 (min.) input impedance, a 10 
W
 (max.) output. 
Features/Benefits:
 Compact 2" x 2" design minimizes board space
requirements.
 Digitally programmable corner frequency allows
selecting cut-off frequencies specific to each appli-
cation.
 Plug-in ready-to-use, reducing engineering de-
sign and manufacturing cycle time.
 Factory-set tuning range, no external clocks or
adjustments needed.
 Broad range of transfer characteristics and corner
frequencies to meet a wide range of applications.
Applications
 Anti-alias filtering
 Data acquisition systems
 Communication systems and electronics
 Medical electronics equipment and research
 Sound and vibration testing
 Real and compressed time data analysis
 Noise elimination
 Signal reconstruction
Programmable Specifications
. . . . . . . . . . . . . . 
Page
Digital Tuning & Control . . . . . . . . . . . . . . . . . . . . . . 2
Available Low-Pass Models:
. . . . . . . . . . . . . . . . . . . 
D824L8B
4-pole Butterworth . . . . . . . . . . . . . . . . . 3
D824L8L
4-pole Bessel . . . . . . . . . . . . . . . . . . . . . 3
D824L8Y2 4-pole Cheby (0.2 dB Ripple) . . . . . . . . . 3
D824L8Y5 4-pole Cheby (0.5 dB Ripple) . . . . . . . . . 3
Available High-Pass Models:
 . . . . . . . . . . . . . . . . . . 
D824H8B
4-pole Butterworth . . . . . . . . . . . . . . . . . 4
D824H8Y2 4-pole Cheby (0.2 dB Ripple) . . . . . . . . . 4
D824H8Y5 4-pole Cheby (0.5 dB Ripple) . . . . . . . . . 4
General Specifications:
Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . 5
Pin-out/package data. . . . . . . . . . . . . . . . . . . . . . . . . 5