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9
Calibration Screen
9.1
How to Calibrate
9.2
To Calibrate the bq20z70
9.3
Board Offset Calibration
9.4
Pack Voltage Calibration
Calibration Screen
The bq20z70 allows for an automatic data flash export function, similar to the SBS Data logging function.
This feature, when selected via | Options | Auto Export |, exports Data Flash to a sequential series of files
named as FilenameNNNNN.gg where N = a decimal number from 0 to 9.
The AutoExport interval is set under the | Options menu | with a minimum value of 15 seconds. The
AutoExport filename is also set under the | Options menu |.
When there is a check next to | AutoExport |, the AutoExport is in progress. The same menu selection is
used to turn on/off AutoExport.
If the data flash screen is blank, then the bq20z70 that is being used may not be supported by the
bqEVSW version that is being used. An upgrade may be required.
Before the bq20z70 is calibrated:
•
Connect a load to Pack- and Pack+ that draws approximately 2 A and measures discharge current to
use the FETs.
•
Connect a current source to Batt- and Pack- to calibrate without using the FETs.
•
Measure the pack voltage from Batt+ to Batt- (Total of Cell voltages).
•
Measure the temperature of the pack.
•
These steps may or may not be required, depending on the type of calibration being performed.
Select the types of calibration to be performed.
Enter the measured values for the types selected (Except for CC Offset Calibration).
If Voltage Calibration is selected, then enter the number of cells on the pack.
If Temperature Calibration is selected, then select the sensor that is to be calibrated.
If the load is connected between Pack+ and Pack-, then select the Use FETs check box.
Press the Calibrate Part button.
This performs the offset calibration for the current offset of the board.
Remove load/external voltage.
Press the Software Board Offset Calibration button.
This calibrates the voltage at the AFE Pack pin.
Make sure Voltage Calibration has been performed for the pack. If Voltage Calibration is not performed,
then Pack Voltage Calibration calibrates incorrectly.
Remove load/external voltage applied between Pack+ and Pack-.
Press the Pack Voltage button to calibrate.
SLUU242A – May 2006 – Revised June 2006
bq20z70EVM-001 SBS 1.1 Impedance Track™Technology
15
Enabled Battery Management Solution Evaluation Module
