Data Sheet

AD8418A

Rev. C | Page 13 of 17

EXTERNAL REFERENCED OUTPUT

output equal to the reference voltage when there is no differential

input (see Figure 31). The output decreases the reference voltage

when the input is negative, relative to the −IN pin, and increases

the voltage when the input is positive, relative to the −IN pin.

–

+

R1

OUT

GND

AD8418A

R2

R3

R4

–IN

+IN

2.5V

Figure 31. External Referenced Output

SPLITTING THE SUPPLY

the output is set at half of the supply when there is no differential

input (see Figure 32). The benefit of this configuration is that

an external reference is not required to offset the output for

bidirectional current measurement. Tying one reference pin

that is ratiometric to the supply, which means that if the supply

increases or decreases, the output remains at half the supply. For

example, if the supply is 5.0 V, the output is at half scale or 2.5 V. If

the supply increases by 10% (to 5.5 V), the output increases

to 2.75 V.

–

+

R1

OUT

GND

AD8418A

R2

R3

R4

–IN

+IN

Figure 32. Split Supply

SPLITTING AN EXTERNAL REFERENCE

Use the internal reference resistors to divide an external reference

by 2 with an accuracy of approximately 0.5%. Split an external

–

+

R1

OUT

GND

AD8418A

R2

R3

R4

–IN

+IN

5V

Figure 33. Split External Reference