Set R
1
= R
2
V+
0V to 10V
In
12.5kΩ
1kΩ
7
INA132
+15V
2
OPA27
V
2
2
40kΩ
40kΩ
6
REF10
6
10V
For 4-20mA applications,
the REF10 sets the 4mA
low-scale output for 0V input.
V
3
4
4
I
O
= 4 to 20mA
R
LOAD
3
R
1
50.1Ω
2N3904
5
50kΩ
40kΩ
40kΩ
1
R
2
50.1Ω
I
O
= V
3
– V
2
1
1
+
40kΩ R
2
FIGURE 7. Precision Voltage-to-Current Conversion.
The difference amplifier is a highly versatile building
block that is useful in a wide variety of applications. See
the INA105 data sheet for additional applications ideas,
including:
• Current Receiver with Compliance to Rails
• Precision Unity-Gain Inverting Amplifier
•
±10V
Precision Voltage Reference
•
±5V
Precision Voltage Reference
• Precision Unity-Gain Buffer
• Precision Average Value Amplifier
• Precision G = 2 Amplifier
• Precision Summing Amplifier
• Precision G = 1/2 Amplifier
• Precision Bipolar Offsetting
• Precision Summing Amplifier with Gain
• Instrumentation Amplifier Guard Drive Generator
• Precision Summing Instrumentation Amplifier
• Precision Absolute Value Buffer
• Precision Voltage-to-Current Converter with Differential
Inputs
• Differential Input Voltage-to-Current Converter for Low
I
OUT
• Isolating Current Source
• Differential Output Difference Amplifier
• Isolating Current Source with Buffering Amplifier for
Greater Accuracy
• Window Comparator with Window Span and Window
Center Inputs
• Precision Voltage-Controlled Current Source with Buff-
ered Differential Inputs and Gain
• Digitally Controlled Gain of
±1
Amplifier
®
9
INA132