
Instrumentation Amplifier
An instrumentation circuit is shown in Figure 5. The
high CMRR of the CLC436 benefits this application.
The resistors are kept equal to improve the overall
CMRR.
Figure 5: Instrumentation Amplifier
2nd Order Sallen-Key Band-Pass Filter
The CLC436 is well suited for Sallen-Key type active
filters. Figure 6 illustrates the band pass topology
and design equations. For optimum high frequency
performance:
Keep the resistor values between 10
and 1k
Keep the capacitor values between 10pF
and 500pF
Begin design by choosing reasonable values for C
1
and C
2
and then setting the desired mid-band gain.
Figure 6: Sallen-Key Active Filter
V
1
500
500
+
CLC436
-
500
500
-
+
500
R
1
CLC436
50
-
+
CLC436
500
500
V
2
V
o
= 3(V
2
-V
1
)
R
f
R
g
R
3
CLC436
-
R
1
V
in
V
o
R
2
C
2
C
1
+
C
1
5C
G
1
R
R
, desired mid band gain
R
2
Q
GC 2 f
, where f
desiredcenter frequency
R
GR
1 4.8Q
2G
G
1
4.8Q
2G
G
R
5GR
1 4.8Q
2G
G
G 1
4Q
2
1
f
g
1
2
1
2
2
2
2
3
1
2
2
2
=
= +
=
)
=
=
+
+
+
=
+
+
C
2
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6
Lit #150436-004
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