LM158,A-LM258,A-LM358,A
HIGH INPUT Z, DC DIFFERENTIAL AMPLIFIER
USING SYMMETRICAL AMPLIFIERS TO
REDUCE INPUT CURRENT
R2
100kW
R1
100kW
1/2
LM158
R4
100kW
R3
100kW
1/2
LM158
I
e
I
I
B
I
I
B
1/2
LM158
e
o
2N 929
0.001
m
F
+V1
+V2
V
o
I
B
I
B
3MW
I
B
1/2
LM158
if R1 = R5 and R3 = R4 = R6 = R7
e
o
= [ 1 + 2
R
1 ] ( (e
2
+ e
1
)
-----------
R2
As shown e
o
= 101 (e
2
+ e
1
)
1.5MW
Input current compensation
HIGH INPUT Z ADJUSTABLE GAIN DC
INSTRUMENTATION AMPLIFIER
R1
100k
W
R3
100k
W
R4
100k
W
LOW DRIFT PEAK DETECTOR
e
1
1/2
LM158
I
B
e
O
R2
2k
W
Gain adjust
1/2
LM158
R5
100k
W
1/2
LM158
I
B
C
1m F
2I
B
1/2
LM158
e
o
Z
o
e
I
1/2
LM158
e
2
R6
100k
W
R7
100k
W
Z
I
2I
B
2N 929
0.001m F
I
B
3R
3MW
I
B
1/2
LM158
if R1 = R5 and R3 = R4 = R6 = R7
e
o
= [ 1 + 2
R
1 ] ( (e
2
+ e
1
)
-----------
R2
R
1MW
Input current
compensation
As shown e
o
= 101 (e
2
+ e
1
)
ACTIVE BAND-PASS FILTER
R1
100kW
C1
330pF
R2
100kW
+V1
1/2
LM158
R5
470kW
1/2
LM158
R4
10MW
C2
R3
100kW
330 pF
1/2
LM158
R6
470kW
V
o
R7
100kW
V
CC
R8
100kW
C3
10m F
8/12