ds2760bx-025-t-r Maxim Integrated Products, Inc., ds2760bx-025-t-r Datasheet - Page 9

• Manufacturer Part Number: ds2760bx-025-t-r
• Description: Ds2760 High-precision Li+ Battery Monitor
• Manufacturer: Maxim Integrated Products, Inc.

resistor, the DS2760 maintains the Current Accumulator in units of Volt-hours, with a resolution of
6.25 mVhrs and a full scale range of ±205 mVhrs.
The Current Accumulator is a read/write register that can be altered by the host system as needed.
CURRENT ACCUMULATOR FORMAT Figure 5
CURRENT OFFSET COMPENSATION
Current measurement and the current accumulation are both internally compensated for offset on a
continual basis minimizing error resulting from variations in device temperature and voltage.
Additionally a constant bias may be utilized to alter any other sources of offset. This bias resides in
EEPROM address 33h in two’s-complement format and is subtracted from each current measurement.
The current offset bias is applied to both the internal and external sense resistor configurations. The
factory default for the current offset compensation is a value of 0.
CURRENT OFFSET BIAS Figure 6
VOLTAGE MEASUREMENT
The DS2760 continually measures the voltage between pins VIN and VSS over a range of 0 to 4.75V.
The resulting data is placed in the Voltage Register in two’s-complement format with a resolution of
4.88mV. Voltages above the maximum register value are reported as the maximum value. The Voltage
Register format is shown in Figure 7.
VOLTAGE REGISTER FORMAT Figure 7
MSb
MSb
S
S
2
2
14
9
MSB—Address 0C
MSB—Address 10
2
2
13
8
2
2
12
7
2
2
11
MSb
6
S
2
2
10
5
2
6
2
2
9
4
2
5
LSb
LSb
2
2
Units: 0.625 mA for internal sense resistor
Address 33
8
3
2
4
15.625 mV for external sense resistor
9
2
3
MSb
MSb
2
2
7
2
2
2
2
2
6
1
2
1
Units: 0.25 mAhrs for internal sense resistor
LSb—Address 0D
LSb—Address 11
2
2
LSb
5
0
2
0
6.25 mVhrs for external sense resistor
2
X
4
2
X
3
2
X
2
Units: 4.88 mV
2
X
1
LSb
LSb
2
X
0