BQ28Z560-R1_14 Datasheet, PDF (35/61 Pages) Texas Instruments – Single Cell Li-Ion Battery Gas Gauge

Not Recommended For New Designs
bq28z560-R1
www.ti.com
SLUSBD3 – APRIL 2013
Avg P Last Run
The bq28z560-R1 logs the power averaged from the beginning to the end of each discharge cycle. It stores this
average power from the previous discharge cycle in this register. To get a correct average power reading, the
bq28z560-R1 continuously multiplies instantaneous current times Voltage() to get power. It then logs this data to
derive the average power. This register should never need to be modified. It is only updated by the bq28z560-R1
when required.
Delta Voltage
The bq28z560-R1 stores the maximum difference of Voltage() during short load spikes and normal load, so the
Impedance Track algorithm can calculate remaining capacity for pulsed loads.
NOTE
It is not recommended to change this value.
Ra Tables and Ra Filtering Related Parameters
These tables contain encoded data and are automatically updated during device operation. The bq28z560-R1
has a filtering process to eliminate unexpected fluctuations in Ra values while the Ra values are being updated.
The DF parameters RaFilter, RaMaxDelta, MaxResfactor, and MinResfactor control the Filtering process of Ra
values. RaMaxDelta Limits the change in Ra values to an absolute magnitude. MinResFactor and MaxResfactor
parameters are cumulative filters that limit the change in Ra values to a scale on a per discharge cycle basis.
These values are data flash configurable. No further user changes should be made to Ra values except for
reading/writing the values from a pre-learned pack (part of the process for creating golden image files).
MaxScaleBackGrid
The MaxScaleBackGrid parameter limits the resistance grid point after which back scaling will not be performed.
This variable ensures that the resistance values in the lower resistance grid points remain accurate while the
battery is at a higher DoD state.
Max DeltaV, Min DeltaV
This is the Maximal/Minimal value allowed for delta V, which will be subtracted from simulated voltage during
remaining capacity simulation.
Qmax Max Delta %
This is the maximal change of Qmax during one update, as a percentage of Design Capacity. If the gauge
attempts to change the Qmax value and this delta change value exceeds the Qmax Max delta % limit, the
change value will be capped to the old value ± DesignCapacity×QmaxMaxDelta/100.
Fast Resistance Scaling
This new algorithm improves convergency of Remaining Capacity and terminates voltage at end of discharge.
The algorithm is enabled when cell voltage goes below (Terminate Voltage + Term V Delta) or StateofCharge()
goes below Fast Scale Start SOC. For most applications, the default value of Term V Delta and Fast Scale Start
SOC are recommended.
DeltaV Max Delta
This is the maximal change of the Delta V value. If an attempted change of the value exceeds this limit, the
change value will be capped to the old value ±DeltaV Max Delta.
Lifetime Data Logging Parameters
NOTE
IT_ENABLE must be enabled (Command 0x0021) for Lifetime Data logging functions to
be active.
Copyright © 2013, Texas Instruments Incorporated
Product Folder Links: bq28z560-R1
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