Current Register 04h (Read-Only)

Current=

ShuntVoltage

CalibrationRegister

´

4096

CALIBRATION REGISTER

Calibration Register 05h (Read/Write)

INA220

Full-scale range and LSB depend on the value entered in the Calibration Register. See the Programming the

INA220 Power Measurement Engine section. Negative values are stored in Two's Complement format.

BIT #

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

BIT

CSIGN

CD14

CD13

CD12

CD11

CD10

CD9

CD8

CD7

CD6

CD5

CD4

CD3

CD2

CD1

CD0

NAME

POR

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

VALUE

The value of the Current Register is calculated by multiplying the value in the Shunt Voltage Register with the

value in the Calibration Register according to the equation:

Current and power calibration are set by bits D15 to D1 of the Calibration Register. Note that bit D0 is not used in

the calculation. This register sets the current that corresponds to a full-scale drop across the shunt. Full-scale

range and the LSB of the current and power measurement depend on the value entered in this register. See the

Programming the INA220 Power Measurement Engine section. This register is suitable for use in overall system

calibration. Note that the '0' POR values are all default.

BIT #

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

(1)

BIT

FS15

FS14

FS13

FS12

FS11

FS10

FS9

FS8

FS7

FS6

FS5

FS4

FS3

FS2

FS1

FS0

NAME

POR

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

VALUE

(1)

D0 is a void bit and will always be '0'. It is not possible to write a '1' to D0. CALIBRATION is the value stored in D15:D1.

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