DS2751 Maxim Integrated Products, DS2751 Datasheet - Page 9

• Manufacturer Part Number: DS2751
• Description: Multichemistry Fuel Garge
• Manufacturer: Maxim Integrated Products

Figure 4. CURRENT ACCUMULATOR FORMAT
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 can 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 bias is a value of 0.
Figure 5. CURRENT OFFSET BIAS
VOLTAGE MEASUREMENT
The DS2751 continually measures the voltage between pins V
Voltage Register is updated in two’s-complement format every 3.4ms 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 6.
Figure 6. VOLTAGE REGISTER FORMAT
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
Units: 0.625mA for internal sense resistor
5
LSb
LSb
2
Address 33
2
8
3
2
15.625mV for external sense resistor
9 of 19
4
2
MSb
3
MSb
2
2
7
2
2
2
2
2
6
1
IN
Units: 0.25mAhrs for internal sense resistor
2
1
LSB—Address 0D
LSB—Address 11
and V
2
2
LSb
5
0
2
6.25mVhrs for external sense resistor
0
2
X
SS
4
over a 0 to 4.5V range. The
2
X
3
2
X
2
Units: 4.88 mV
2
X
1
LSb
LSb
2
X
0