DG300A/301A/302A/303A
Applications (Cont’d)
+15 V
–15 V
+15 V
R
4
+
–
CMOS Logic
Input Select
High = Diff. IN B
Diff. IN A
–15 V
75 kW
+15 V
R
2
R
6
75 kW
75 kW
Diff. IN B
V
R
16 kW
Ri
DG301A
GND
OUT
1
1
DG302A
1.5 kW
R
2
75 kW
+15 V
CMOS Logic
Gain Select
High = A = 101
V
NULL
OS
R
R
7
5
V
50 kW
75 kW
67 kW
Voltage gain of the instrumentation amplifier is:
2R
–15 V
2
A
V
=
1
+
(In the circuit s=hown1,0.4,A A= 101)
V1 V2
R
1
Figure 6. Low Power Instrumentation Amplifier with Digitally Selectable Inputs and Gain
10
Siliconix
S-52880—Rev. C, 28-Apr-97