824L8B Datasheet, PDF (2/13 Pages) List of Unclassifed Manufacturers – 2 X 2 4-Pole Filters

824 Series
8-Bit Programmable Filters
Digital Tuning &
Control Characteristics
Digital Tuning Characteristics
Pin-Out Key
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 (D₀ - D₇).
Filter tuning follows the tuning equation given below:
fc = ( fmax/256 ) [ 1 + D₇ x 2⁷ + D₆ x 2⁶ + D₅ x 2⁵ + D₄ x 2⁴ + D₃
x 2³ + D₂ x 2² + D₁ x 2¹ + D₀ x 2⁰ ]
where D₁ - D₇ = "0" or "1", and
fmax = Maximum tuning frequency;
fc = corner frequency;
Minimum tunable frequency = fmax/256 (D₀ thru D₇ = 0);
Minimum frequency step (Resolution) = fmax/256
Data Input Specifications
Input Data Levels (CMOS Logic)
Input Voltage (Vs = 15 Vdc)
Low Level In
0 Vdc min.
High Level In
11 Vdc min.
4 Vdc max.
15 Vdc max.
Input Current
High Level In
Low Level In
- 10 ^-5 mA typ. -1 mA max..
+10 ^-5 mA typ. +1 mA max.
Input Capacitance
5 pF typ
7.5 pF max.
Input Data Format Frequency Select Bits
Positive Logic
Logic "1" = +Vs
Logic "0" = Gnd
Bit Weighting
D₀
D₇
(Binary-Coded)
LSB (least significant bit)
MSB (most significant bit)
Frequency Range
256 : 1, Binary Weighted
IN Analog Input Signal
OUT Analog Output Signal
GND Power and Signal Return
+Vs Supply Voltage, Positive
-Vs Supply Voltage, Negative
Os Offset Adjustment
OUT +Vs -Vs
D₇ Tuning Bit 7 (MSB)
D₆ Tuning Bit 6
D₅ Tuning Bit 5
D₄ Tuning Bit 4
D₃ Tuning Bit 3
D₂ Tuning Bit 2
D₁ Tuning Bit 1
D₀ Tuning Bit 0 (LSB)
2.00
IN Os ⁴
Bottom View
D₇
D₆
D₅
D₄
GND
D₃
D₂
D1
D₀
MSB ---
---
---
---
---
---
LSB
Bit
Weight
2⁷ 2⁶ 2⁵ 2⁴ 2³ 2² 2¹ 2⁰
fc
Corner
D₇ D₆ D₅ D₄ D₃ D₂ D₁ D₀ Frequency
0
0
0
0
0
0
0
0 fmax/256
0
0
0
0
0
0
0
1 fmax/128
0
0
0
0
0
0
1
1 fmax/64
0
0
0
0
0
1
1
1 fmax/32
0
0
0
0
1
1
1
1 fmax/16
0
0
0
1
1
1
1
1 fmax/8
0
0
1
1
1
1
1
1 fmax/4
0
1
1
1
1
1
1
1 fmax/2
1 1 1 1 1 1 1 1 fmax
2
25 Locust St, Haverhill, Massachusetts 01830 • Tel: [phone] • FAX: [phone]
e-mail: [e-mail] • Web Address: http://www.freqdev.com