V

O

R

2

R

1

1

Gain Set by R

Output Offset =

(V

R

a) Using resistor divider.

V

O

R

L

1

REF200

100µA

V+

V

R

Gain Set by R

L

Output Offset = (100µA)(R

(independent of V+)

b) Using current source.

INA139

3

4

INA139

3

4

40

30

20

10

0

–10

–20

100

1k

10k

100k

1M

10M

Frequency (Hz)

R

R

R

INA139, INA169

www.ti.com

SBOS181E – DECEMBER 2000 – REVISED DECEMBER 2015

Typical Applications (continued)

8.2.2.3 Application Curve

Figure 13. Gain vs Frequency

8.2.3 Offsetting the Output Voltage

For many applications using only a single power supply it may be required to level shift the output voltage away

from ground when there is no load current flowing in the shunt resistor. Level shifting the output of the INA139 or

INA169 devices is easily accomplished by one of two simple methods shown in Figure 14. The method on the

left hand side of Figure 14 illustrates a simple voltage divider method. This method is useful for applications that

require the output of the INA138 or INA168 devices to remain centered with respect to the power supply at zero

require a fixed value of output offset, independent of the power supply voltage, the current source method shown

on the right-hand side of Figure 14 is recommended. With this method a REF200 constant current source is used

Figure 14. Offsetting the Output Voltage

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