DS2792 Programmable Fuel Gauge with UART Interface

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Figure 17. Current Register Format

12-bit + sign resolution (13-bit), 88ms update interval

Word Address 6004h

S

2

11

2

10

2

9

2

8

2

7

2

6

2

5

2

4

2

3

2

2

2

1

2

0

X

X

X

MSb

LSb

“S”: sign bit(s)

Units: 2

CURRENT RESOLUTION (1 LSB)

25mŸ

20mŸ

15mŸ

10mŸ

15.625µV

625µA

781µA

1.042mA

1.56mA

CURRENT INPUT RANGE

25mŸ

20mŸ

15mŸ

10mŸ

±64mV

±2.56A

±3.2A

±4.27A

±6.40A

The average current register reports the average of 4096 current samples over a 2.8s measurement period. Figure

18 specifies the update interval and resolution of the average current register. Values are posted in the same

format as the current register, but with an additional 3 bits of resolution. Positive currents above the maximum

register value are reported at the maximum value, 7FFFh. Negative currents below the minimum register value are

reported at the minimum value, 8000h.

Figure 18. Average Current Register Format

15-bit + sign resolution (16-bit), 2.8s update interval

Word Address 6009h

S

2

14

2

13

2

12

2

11

2

10

2

9

2

8

2

7

2

6

2

5

2

4

2

3

2

2

2

1

2

0

MSb

LSb

“S”: sign bit(s)

Units: 2

AVERAGE CURRENT RESOLUTION (1 LSB)

25mŸ

20mŸ

15mŸ

10mŸ

1.953µV

78.13µA

97.66µA

130.2µA

195.3µA

Automatic Current Offset Correction

Continuous offset cancellation is performed automatically to correct for offsets in the current measurement system.

Individual values reported by the current register have a maximum offset of ±0.5 bits (±7.8125µV). Individual values

reported in the average current register have a maximum offset of ±4 bits (±7.8125µV).