I

S

OPA340

INA139

3

4

Z

IN

R

L

Copyright © 2017, Texas Instruments Incorporated

VOLTAGE GAIN

EXACT R L ( Ω )

NEAREST 1% R L (Ω )

1

1k

1k

2

2k

2k

5

5k

4.99k

10

10k

10k

20

20k

20k

50

50k

49k

100

100k

100k

Shunt

R

S

INA139

2

1

OUT

Q1

R

L

I

O

+

V

O

–

Load

R

G1

1kΩ

R

G2

1kΩ

V

IN+

V

IN–

3

4

I

S

V+

5

V+ power can be

common or

independent of

load supply.

2.7 V≤ (V+) ≤ 40 V(1)

V

P

Load Power Supply

2.7 V to 40 V (1)

Copyright © 2017, Texas Instruments Incorporated

12

INA139, INA169

SBOS181F – DECEMBER 2000 – REVISED FEBRUARY 2017

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Product Folder Links: INA139 INA169

Submit Documentation Feedback

Copyright © 2000–2017, Texas Instruments Incorporated

Application Information (continued)

(1)

For the INA169 device, maximum VP and V+ voltage is 60 V.

Figure 9. Basic Circuit Connections

8.2 Typical Applications

The INA139 is designed for current shunt measurement circuits, as shown in Figure 9, but its basic function is

useful in a wide range of circuitry. A creative engineer will find many unforeseen uses in measurement and level

shifting circuits. A few ideas are illustrated in Figure 14 through Figure 18.

8.2.1 Buffering Output to Drive an ADC

(1)

Buffer of amp drives the A/D converter without effecting gain

Figure 10. Buffering Output to Drive the A/D Converter

8.2.1.1 Design Requirements

Digitize the output of the INA139 or INA169 devices using a 1-MSPS analog-to-digital converter (ADC).