824BP Series
Band Pass
Description:
The 824BP Series is a 2-pole-pair digitally
programmable precision band-pass active filter that
provides high performance in a compact 2" x 2"
footprint. These new filters take advantage of the
company’s proprietary designs using surface-mount
technology to provide a low profile, compact package
in minimal board space. 824BP filters are factory
tuned to one of three factory set tuning ranges or 8-
bit custom ranges from 1 Hz to 25.6 kHz. Each filter
type features a near theoretical amplitude/phase
response along with low output voltage noise
enabling these filters to achieve a 10,000:1 or better
dynamic signal range.
Pretuned to within ±2% of the center frequency,
band-pass 824BP filters pass all frequencies lying
between the upper and lower -3dB points of the
amplitude response curve. Available Q’s for 824BP
models are 1, 2, 5, or 10.
Features/Benefits:
• Compact 2.0"L x 2.0"W footprint minimizes board
space requirements.
• Plug-in ready-to-use, reducing engineering design
and manufacturing cycle time.
• Factory tuned, no external clocks or adjustments
needed.
• Broad range of center frequencies to meet a wide
range of applications.
Applications
• Power line interference rejection
• Transducer output filtering
• Production test instrumentation
• Medical electronics equipment and research
• Comb filtering and equalization
• Noise and harmonic analysis
• RMS measurements
• Frequency spectrum analysis
1
8 Bit Programmable
2-Pole Pair Filters
Programmable Specifications:
. . . . . . . . . . . .Page
Digital Tuning & Control . . . . . . . . . . . . . . . . . . . . .2
Available Band-Pass Models:
824BP2
2 pole pair . . . . . . . . . . . . . . . . . . .3
General Specifications:
Ordering Information . . . . . . . . . . . . . . . . . . . . . . .4
Pin-Out/package data . . . . . . . . . . . . . . . . . . . . . .4
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
824BP Series
8-Bit Programmable Filters
Digital Tuning Characteristics
The digital tuning interface circuits are a parallel set of eight
(8) 4053 CMOS switches which accept CMOS compatible
inputs for the eight tuning bits (D
0
- D
7
).
Filter tuning follows the tuning equation given below:
f
c
= ( f
max
/256 ) [ 1 + D
7
x 2 + D
6
x 2 + D
5
x 2 + D
4
x 2 +
D
3
x 2 + D
2
x 2 + D
1
x 2 + D
0
x 2 ]
where D
1
- D
7
= "0" or "1", and
f
max
= Maximum tuning frequency;
f
c
= corner frequency;
Minimum tunable frequency = f
max
/256 (D
0
thru D
7
= 0);
Minimum frequency step (Resolution) = f
max
/256
OUT +Vs -Vs
D
7
D
6
D
5
D
4
2.00
GND
D
3
D
2
D
1
3
2
1
0
7
6
5
4
Digital Tuning &
Control Characteristics
Pin-Out Key
IN
OUT
GND
+Vs
-Vs
Os
Analog Input Signal
Analog Output Signal
Power and Signal Return
Supply Voltage, Positive
Supply Voltage, Negative
Offset Adjustment
D
7
Tuning
D
6
Tuning
D
5
Tuning
D
4
Tuning
D
3
Tuning
D
2
Tuning
D
1
Tuning
D
0
Tuning
Bit
Bit
Bit
Bit
Bit
Bit
Bit
Bit
7 (MSB)
6
5
4
3
2
1
0 (LSB)
Data Input Specifications
Input Data Levels
(CMOS Logic)
4 Vdc max.
15 Vdc max.
Input Voltage (Vs = 15 Vdc)
Low Level In
0 Vdc min.
High Level In
11 Vdc min.
Input Current
High Level In
Low Level In
Input Capacitance
Input Data Format
Positive Logic
Bit Weighting
D
0
D
7
Frequency Range
- 10
mA
typ.
-5
+10
mA
typ
.
5 pF typ
-5
D
0
IN Os
4
-1
mA
max.
.
+1
mA
max.
7.5 pF max.
MSB
2
7
Bottom View
---
2
6
Frequency Select Bits
Logic "1" = +Vs
Logic "0" = Gnd
(Binary-Coded)
LSB (least significant bit)
MSB (most significant bit)
256 : 1, Binary Weighted
---
2
5
---
2
4
---
2
3
---
2
2
---
2
1
LSB
2
0
Bit
Weight
Corner
Frequency
fc
D
7
0
0
0
0
0
0
0
0
1
D
6
0
0
0
0
0
0
0
1
1
D
5
0
0
0
0
0
0
1
1
1
D
4
0
0
0
0
0
1
1
1
1
D
3
0
0
0
0
1
1
1
1
1
D
2
0
0
0
1
1
1
1
1
1
D
1
0
0
1
1
1
1
1
1
1
D
0
0
1
1
1
1
1
1
1
1
f
max
/256
f
max
/128
f
max
/64
f
max
/32
f
max
/16
f
max
/8
f
max
/4
f
max
/2
fmax
2
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
824BP Series
Band-Pass
Model
Product Specifications
Size Model 2
Model 3 & 4
Range f
o
Available "Q’s"
1
"Q" Accuracy
Theoretical Transfer
Characteristics
Pass-Band Gain
(non-inverting)
8-Bit Programmable
2-Pole Pair Filters
824BP2
Band-Pass
2.0" x 2.0" x 0.5"
2.0" x 2.0" x 0.4"
1 Hz to 25.6 kHz
1, 2, 5, 10
±10 %
Appendix A
Pages 39 & 40
0 ± 0.25 dB typ
0 ± 0.50 dB max.
12 dB/octave
f
o
±0.01%/°C
FMA-02A
f
O
=
Attenuation Rate
Center Frequency
Stability
Filter Mounting
Assembly
±2% max.
1. Q – Quality Factor for band-pass filters. Q = f
O
/(f
H
-f
L
)
√
f
H
f
L
3
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
824BP Series
Specification
(25°C and Vs ±15Vdc)
Analog Input Characteristics
1
Impedance
Voltage Range
Max. Safe Voltage
Analog Output Characteristics
Impedance (Closed Loop)
Linear Operating Range
2
Maximum Current
3
Offset Voltage
Offset Temp. Coeff.
Power Supply (
±
V)
Rated Voltage
Operating Range
Maximum Safe Voltage
Quiescent Current
Temperature
Operating
Storage
Notes:
1. Input and output signal voltage referenced to supply common.
2. Output is short circuit protected to common.
DO NOT CONNECT TO ±Vs.
3. Adjustable to zero.
4. Units operate with or without offset pin connected.
Pin-Out and Package Data
Ordering Information
Pin-Out & Package Data
2.00
10 k
W
min.
±
10 Vpeak
±
Vs
11
W
typ.
10
W
max.
±
10V
±
2 mA
22
mV typ.
20 mV max.
50
mV/°C
G-3
0.5 0.4
G-1
0.15 min.
0.025 Dia.
Side View
All dimensions are in inches
All Case Dimensions ± 0.02"
Grid Dimensions 0.1" x 0.1"
OUT +Vs -Vs
D
7
±
15 Vdc
±
12 to
±
18 Vdc
±
18 Vdc
2.00
D
6
D
5
D
4
GND
D
3
D
2
D
1
D
0
IN Os
4
±
13 mA typ.
±
20 mA max.
-20
to +70°C
-25 to +85°C
Bottom View
Filter Mounting Assembly-See FMA-02A
Ordering Information
DC Offset Adjustment
± Vs
Do not connect
if trim is not
required.
20 k
W
(Cermet)
OS
824BP2/10-3
“Q”
1, 2, 5, 10
Model
Model
Number
2
3
4
Tuning
Range (Hz)
1.0 to 256
10 to 2560
100 to 25.6k
Minimum
Step(Hz)
1.0
10
100
Case
G-3
G-1
G-1
- Vs
We hope the information given here will be helpful. The information is based on data and our best knowledge, and we consider the information to be true and accurate. Please read all statements,
recommendations or suggestions herein in conjunction with our conditions of sale which apply to all goods supplied by us. We assume no responsibility for the use of these statements,
recommendations or suggestions, nor do we intend them as a recommendation for any use which would infringe any patent or copyright.
PR-824BP-01
4
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
Product Handling
Procedure
Programmable Filter Modules Power Sequence & ESD
November 2000
Programmable Filters Modules
818, 824, 828, 828BP, 828BR, 854, 858, R854, R858
I. Scope
The following precautions are necessary when handling and installing Frequency Devices
programmable filter modules.
II. Digital Circuit Description
The digital input pins connect directly to 4000 series CMOS logic, such as the 4053 analog switch. The
power supply (Vss) for the digital logic on the module comes directly from the +15 Volt pin on the
module. This sets the threshold voltage at 11.0 V minimum to 15.0 V maximum for a "1" (High) level
and 0.0 V minimum to 4.0 V maximum for a "0" (Low) level. Applying a voltage between 4.0 and 11.0
V will produce unpredictable operation. Connecting 5 Volt or 3.3 V logic devices directly to the filter
module without using a voltage translator will result in erratic operation of the filter.
III. (VERY IMPORTANT) Power-Up and Power-Down Sequence
Do not plug-in or un-plug module while power is applied.
It is imperative that power is
supplied to the + 15 V pin on the filter module before or at the same instance that any digital pin is
pulled High (> 0.0 V). Failure to do this will result in excessive current flowing through the digital input
pin and through a protection diode internal to the 4000 logic, which will result in damage to the module.
The proper power-up and power-down sequence is:
1. Connect filter module ground.
2. Connect filter module +15 V.
3. Connect filter module -15 V.
4. Connect the input signal.
All four of the above steps can also occur simultaneously. Power-down should occur in the reverse
order.
IV. ESD Issues
Like most modern electronic equipment, the modules can be damaged by electrostatic discharge (ESD).
The modules are shipped from the factory in sealed, anti-static packaging and should be kept in the
sealed package prior to mounting on a circuit board. The following additional rules should also be
observed when handling the modules after they are removed from the factory packaging:
1. Only a person wearing a properly grounded wrist strap should handle the modules.
2. Any work surface that the modules are placed on must be properly ESD grounded.
3. Any insulating materials capable of generating static charge (such as paper) should be kept
away from the modules.
Static generating clothing should be covered with an ESD-protective smock.
1
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
