Texas Instruments BQ76942EVM, Руководство пользователя

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Figure 3-7. Program OTP Pane with Success Display
3.7 Calibration
The calibration tool may not be available for all versions of devices. When the calibration tool is not available
calibration of the device can be performed by entering values in the calibration section of the data memory.
The calibration writes to the volatile registers in the device which are available in the Data Memory view. When
calibration values are complete they can be written to the OTP with other configuration settings. Calibration
cannot be written to OTP separately from configuration settings.
The EVM and all new boards should be calibrated before operation. The calibration view is shown in Figure 3-8 .
Temperature is typically calibrated first. Board Offset should be calibrated with no current flow and should be
calibrated before Current Gain. The EVM uses a 1-mΩ sense resistor and calibration at low current will result in
some granularity from the current resolution. This may result in an apparent error at higher currents. Calibration
at higher currents will reduce this effect and should be done where it is important.
Voltages and temperatures may be calibrated individually or as a group. All values entered will be calibrated. If
individual values are to be calibrated, leave all the other entries blank. As an example, measure the battery
voltage, calculate the average cell value and enter the value in the box. Clicking the Calibrate Voltage button
runs the calibration. Values left blank or entered as '0' are not calibrated. When successful, a green check
appears next to the button as shown in
Figure 3-9 . If there is an error, a red X appears instead with a message
as shown in Figure 3-10 .
When calibrating the EVM voltage, remember the EVM uses 1% values for the cell simulator resistors.
Measuring each cell voltage value is recommended rather than using a common value if individual cell voltage
calibration is desired.
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SLUUC32A – NOVEMBER 2019 – REVISED OCTOBER 2020
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BQ76942 Evaluation Module 13
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