LTC1562 Linear Technology, LTC1562 Datasheet - Page 16

• Manufacturer Part Number: LTC1562
• Description: Very Low Noise/ Low Distortion Active RC Quad Universal Filter
• Manufacturer: Linear Technology

LTC1562
TYPICAL APPLICATIONS
16
V
5V
IN
0.1 F
C
IN1
8th Order Bandpass Filter, Single 5V Supply,
SCHEMATIC INCLUDES PIN NUMBERS FOR 20-PIN PACKAGE.
PINS 4, 7, 14, 17 (NOT SHOWN) ALSO CONNECT TO V
– 3dB Bandwidth =
C
IN3
R
R21
R23
R
Notes: R
values in the later formulas.
Example: Center frequency f
R
nearest 1% value 47.5k. C
This and the 1% value R22 = 15k also go into the calculation for R
Q1
Quick Design Formulas for Center Frequency f
Q3
Q1
= R
10
Q3
1
2
3
5
6
8
9
Q1
INV B
V1 B
V2 B
V
SHDN
V2 A
V1 A
INV A
, R22 and C
= 51.56k, nearest 1% value 51.1k. R22 = R24 = 15.15k, nearest 1% value 15k. R
+
R21 = R23 = 10.6k
LTC1562
R22 = R24 = 9.7k
C
R
R
IN1
IN2
Center Frequency
IN4
= C
AGND
INV C
INV D
V2 D
V1 D
V1 C
V2 C
IN1
V
IN3
–
U
IN1
10
should be rounded to the nearest standard finite-tolerance value before using these
20
19
18
16
15
13
12
11
= 159pF
C
= C
of 80kHz. The formulas give R21 = R23 = 16.56k, nearest standard 1% value 16.5k.
IN2
100kHz
100kHz
(Basic)
1 F
R22
R
R
R24
R
10k
= 31.11pF using 51.1k for R
Q2
C
C
Q4
Q1
–
2
2
1562 TA07a
V
OUT
C
(Recommended Range 40kHz to 140kHz):
R
R
R
Q1
Q2
IN2
= R
= R
= R
Q3
Q4
IN4
Q1
IN2
= 164.6k
= 143.2k
, nearest standard 5% capacitor value 33pF.
=
= R
(10k)(10.6pF)
R22R
–10
– 20
– 30
– 40
– 50
– 60
–70
– 80
– 90
10
IN4
0
40
100kHz
100kHz
Q1
f
= 65.20k, nearest 1% value 64.9k.
CENTER
48
C
C
C
IN1
56
Amplitude Response
= 80kHz
64
C
C
C
FREQUENCY (kHz)
100kHz
100kHz
100kHz
+ 319kHz
+ 294kHz
+ 286kHz
72
Q2
80
= R
88
Q4
96
= 47.86k,
1562 TA07 TABLE
104
1562 TA07b
112
120