DS2756E+TR MAXIM [Maxim Integrated Products], DS2756E+TR Datasheet - Page 8

• Manufacturer Part Number: DS2756E+TR
• Description: High-Accuracy Battery Fuel Gauge with Programmable Suspend Mode
• Manufacturer: MAXIM [Maxim Integrated Products]

command targeting the ACR register address. A write to the ACR results in an automatic copy of the new value to
EEPROM.
Figure 5. Accumulated Current Register Format
OFFSET ACCUMULATION BLANKING
In order to avoid the accumulation of small positive offset errors over long periods, an offset blanking filter is
provided. The blanking filter is enabled by setting the OBEN bit in the Status Register. When OBEN is set, charge
currents (positive Current register values) between 15.625mV and 62.5mV are not accumulated in the ACR.
Therefore, with R
the ACR.
ACCUMULATION BIAS
Systematic errors or an application preference can require the application of an arbitrary bias to the current
accumulation process. The Accumulation Bias register is provided to allow a user programmed constant positive or
negative polarity bias to the current accumulation process. The Accumulation Bias value can be used to estimate
battery currents that do not flow through the sense resistor, estimate battery self-discharge, or correct for offset
error in the Current register and ACR register. The user programmed two’s complement value in the Accumulation
Bias register is added to the Current Register once per current sample. The register format supports the
accumulation bias to be applied in 1.95mV increments over a ±250mV range. When using a 20mW sense resistor,
the bias control is 100mA over a ±12.5mA range.
The Accumulation Bias register is directly read and write accessible. The user value is made non-volatile with a
Copy Data command targeting EEPROM block 0. The Accumulation Bias register is loaded from EEPROM
memory on power up and a transition from Sleep to Active mode.
MSb
S
2
14
SNS
= 0.020W, positive currents between 0.78mA and 3.125mA are blanked from accumulation in
±204.8mVh
2
V
V
6.25mVh
MSB-Address 10h
13
IS1
IS1
- V
- V
2
12
IS2
IS2
2
11
312.5mAh
±10.24Ah
2
10
20mW
20mW
2
9
LSb
ACR RANGE
2
8
ACR LSB
416.7mAh
8 of 26
±13.65Ah
15mW
15mW
MSb
2
7
R
R
SNS
SNS
2
±20.48Ah
6
625mAh
10mW
10mW
2
LSB-Address 11h
5
2
Units:
4
1.250mAh
±40.96Ah
2
3
5mW
5mW
6.25mVh/R
2
2
2
1
LSb
SNS
2
0