33.3kW

33.3kW

Æ

1

Æ

2

Æ

2

Æ

1

Æ

2

Æ

2

Zer

-

Drift

Æ

OUT

REF2

REF1

GND

V+

V+

Output

REF3020

2.048V

Reference

PRODUCT

GAIN

50V/V

100V/V

INA286

200V/V

INA283

500V/V

INA284

1000V/V

INA285

INA282

Supply

14V to +80V

-

Load

+IN

-

IN

Æ

1

Æ

1

INA282, INA283

INA284, INA285

INA286

www.ti.com

SBOS485A – NOVEMBER 2009 – REVISED JULY 2010

BIDIRECTIONAL OPERATION

Bidirectional operation allows the INA282 family to measure currents through a resistive shunt in two directions.

In this case, the output can be set anywhere within the limits of what the reference inputs allow (that is, between

0V to 9V, but never to exceed the supply voltage). Typically, it is set at half-scale for equal range in both

directions. In some cases, however, it is set at a voltage other than half-scale when the bidirectional current is

nonsymmetrical.

The quiescent output voltage is set by applying voltage(s) to the reference inputs. REF1 and REF2 are

connected to internal resistors that connect to an internal offset node. There is no operational difference between

the pins.

External Reference Output

Connecting both pins together and to a reference produces an output at the reference voltage when there is no

differential input; this configuration is illustrated in Figure 36. The output moves down from the reference voltage

when the input is negative relative to the –IN pin and up when the input is positive relative to the –IN pin. Note

that this technique is the most accurate way to bias the output to a precise voltage.

Figure 36. External Reference Output

Copyright © 2009–2010, Texas Instruments Incorporated

Submit Documentation Feedback

17

Product Folder Link(s): INA282 INA283 INA284 INA285 INA286