DS2760
When the internal sense resistor is used, the DS2760 maintains the Current Accumulator in units of Amp-
hours, with a resolution of 0.25 mAhrs and full scale range of ±8.2 Ahrs. When using an external sense
resistor, the DS2760 maintains the Current Accumulator in units of Volt-hours, with a resolution of
6.25 µVhrs 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
MSB—Address 10
S 214 213 212 211 210 29 28
MSb
LSb
LSB—Address 11
27 26 25 24 23 22 21 20
MSb
LSb
Units: 0.25 mAhrs for internal sense resistor
6.25 µVhrs for external sense resistor
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.
CURRENT OFFSET BIAS – Figure 6
Address 33
S 26
MSb
25 24 23 22 21 20
LSb
Units: 0.625 mA for internal sense resistor
15.625 µV for external sense resistor
VOLTAGE MEASUREMENT
The DS2760 continually measures the voltage between pins VIN and VSS over a range of 0 to 5-volts.
The resulting data is placed in the Voltage Register in two’s-complement format with a resolution of
4.88 mV. 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—Address 0C
S 29 28 27 26 25 24 23
MSb
LSb
LSB—Address 0D
22 21 20 X X X X X
MSb
LSb
Units: 4.88 mV
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