TYPICAL APPLICATIONS
Precision High-Gain Differential Amplifier
R2
+15V
1MΩ
0.1µF
R1
2-
7
1kΩ
R3
1kΩ
6
OP-77E
3+
4 0.1µF
R4
1MΩ
-15V
AMSOP-77
The high gain, gain linearity, CMRR, low TCVOS of the OP-77
make it possible to obtain performance not previously available in
single stage very high-gain amplifier applications.
For the best CMR, R1 must equal R3 . In this example, with a
R2
R4
10mV differential signal, the maximum errors are as listed.
TYPE
COMMON-MODE VOLTAGE
GAIN LINEARITY, WORST CASE
TCVOS
TCIOS
AMOUNT
0.01%/V
0.02%
0.008%/°C
0.008%/°C
R1
VIN
100kΩ
R2
100kΩ
Basic Current Source
Bilateral Current Source
R3
1kΩ
2-
6
OP-77
3+
R4
990Ω
R5
10Ω
IOUT≤ 15mA
R1
VIN
R2
These current sources will supply both positive and negative current into a grounded
load.
R5 ⎜⎛ R4 + 1⎟⎞
Note that
ZO =
⎝ R2
R5 + R4 −
⎠
R3
and that for ZO to be indefinite,
R5 + R4 must = R3 .
R2
R1
R2 R1
100mA current Source
R3
+15V
2-
OP-77
3+
6 50Ω
R4
2N2222
2N2907
R5
-15V
IOUT≤ 100mA
IOUT = VIN R3
R1* R5
GIVEN R3= R4+R5, R1=R2
Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723