lt1568 Linear Technology Corporation, lt1568 Datasheet - Page 12

• Manufacturer Part Number: lt1568
• Description: Very Low Noise, High Frequency Active Rc, Filter Building Block
• Manufacturer: Linear Technology Corporation

DUAL 2nd ORDER LOWPASS FILTER DESIG S
LT1568
12
BAT54S
V
IN1
V
V
0.1 F
OUTA
OUTA
–20
–30
–50
–70
–80
–90
–10
–40
–60
R11
10
0
2nd Order Butterworth, f
0.1
0.1 F
Dual 2nd Order Lowpass Filter,
R31
R21
Dual Supply Operation
Amplitude Response
–5V
5V
FREQUENCY (MHz)
1
2
3
4
5
6
7
8
1
V
INVA
SA
OUTA
OUTA
GNDA
NC
V
+
–
LT1568
Table 1. Resistor Values in Ohms, Dual 2nd Order
Butterworth, Gain = 1, R12 = R11, R22 = R21, R32 = R31
GNDB
OUTB
OUTB
INVB
CUTOFF
SB
EN
V
V
+
–
1568 TA03
16
15
14
13
12
11
10
9
10
1568 TA07
= 1MHz
f
CUTOFF
20
R32
R22
0.2
0.5
R
10
f
1
2
3
4
5
6
7
8
9
C
11 = R21 = R31 = R = 128
(MHz)
f
CUTOFF
R12
V
V
OUTB
OUTB
V
IN2
•
10MHz
V
V
500mV/DIV
200mV/DIV
OUTA
OUTA
V
f
C
IN1
OUTPUT
INPUT
R11 = R21 = R31
0.1 F
R11
U
6340
2550
1270
634
422
324
255
210
182
162
143
127
2nd Order Butterworth, f
R31
R21
Dual 2nd Order Lowpass Filter,
2.7V V
0.1 F
Single Supply Operation
Transient Response
+
1
2
3
4
5
6
7
8
10V
V
INVA
SA
OUTA
OUTA
GNDA
NC
V
+
–
1 s/DIV
LT1568
GNDB
OUTB
OUTB
INVB
V
SB
EN
V
+
–
CUTOFF
16
15
14
13
12
11
10
1568 TA04
9
= 1MHz
R32
R22
1568 TA08
R12
V
V
V
IN2
OUTB
OUTB
1568f