Datasheet

19
LT1251/LT1256
TYPICAL APPLICATIONS
U
Vω (V)
0
350
300
250
200
150
100
50
0
1.5
1251/56 TA15b
0.5 1.0 2.0 2.5
PEAK FREQUENCY OF BP (kHz)
V
FS
= 2.5V
Center Frequency vs Control Voltage Vω
Q vs Control Voltage V
Q
1.5k
500Ω
1251/56 TA15a
2
8
V
IN
500pF
500pF
14
13
121053
1
V
C
R
C
R
FS
V
FS
V
FS
LT1256
–
+
–
+
2
1
1.5k
HP
OUT
BP
OUT
LP
OUT
1k
1k
1k
1.5k
1.5k
1k
1k
1k
1k
500pF
500pF
1.5k
2
8
14
13
121053
1
V
C
R
C
R
FS
V
FS
V
FS
LT1256
–
+
–
+
2
1
1.5k1.5k
2
8
14
13
12 10 5 3
1
V
C
R
C
R
FS
V
FS
V
FS
V
FS
= 2.5V
V
Q
LT1256
–
+
–
+
2
1
–
+
LT1252
Vω
Vω
V
Q
(V)
0
Q
6
5
4
3
2
1
0
0.5 1.0 1.5 2.0
1251/56 TA15c
2.5
V
FS
= 2.5V
State Variable Filter with Adjustable Frequency and Q