Hello Stephanie,

SeeTRM section 3.4 Voltage Measurement and Calibration and production guide www.ti.com/.../slua665.pdf

Dear Shirish,

thanks for your reply. But I still missing detail information about the commands we have to send for the different calibration procedures.

Could you please give us some more detailes about the calibration procedures.

Best regards

Stephanie

Hello Stephanie,

Which particular calibration procedure do you need?

Dear Shirish,

At a first step we are going to implement CC-Offset calibration. All other calibration procedures should successively follow.

Best regards

Stephanie

Hello Stephanie,

This should outline all the steps for manual calibration.

2. General Processes

2.1. CC Offset

The CC offset calibration is mostly done by the gauge, we just need to poll the CCA bit until it is complete.

General procedure:

1. make sure CAL_ENABLE is set, if not enable it: 0x002D
2. Send the ENTER_CAL command: 0x0081
3. Send the CC_OFFSET command to begin the process: 0x000A
4. Pull the CCA bit until it clears (can take some time to clear, up to a minute possibly): CCA can be read from the CONTROL_STATUS command, 0x0000, high byte, bit 3.
5. When CCA clears, send CC_OFFSET_SAVE: 0x000B
6. Send EXIT_CAL: 0x0080
7. Send CAL_ENABLE again to exit calibration mode: 0x002D

2.2. Board Offset

The board offset calibration is very similar to the CC offset. We poll the BCA bit instead of only the CCA. The CC_OFFSET procedure can be referenced for the board offset.

1. make sure CAL_ENABLE is set, if not enable it: 0x002D
2. Send the ENTER_CAL command: 0x0081
3. Send the CC_OFFSET command to begin the process: 0x000A
4. Pull the CCA and BCA bits until they clear (can take some time to clear, up to a minute possibly): CCA can be read from the CONTROL_STATUS command, 0x0000, high byte, bit 3. BCA is high byte, bit 2.
5. When CCA clears, send CC_OFFSET_SAVE: 0x000B
6. Send EXIT_CAL: 0x0080
7. Send CAL_ENABLE again to exit calibration mode: 0x002D

2.3. Gathering Raw Calibration Values

The raw voltage, current, and temperature data from the ADC is needed to do calibration on those parameters.

2.4. Voltage Calibration

The voltage calibration will vary slightly from the BQ35100 flow chart, we want to modify the Voltage Divider calibration parameter instead of vOffset. Instead of the vOffset =Voltage()-avgRawVoltage stage, the following equation should be used and Voltage Divider should be updated in DF.

newVoltageDivider = oldVoltageDivider*(forcedVoltage/rawVoltage)

2.5. Temperature Calibration

Temperature calibration is the same for BQ34Z100-G1 and BQ35100.

2.6. Current Calibration

Current calibration is the same for BQ34Z100-G1 and BQ35100.

2.7. Floating Point Conversion

Floating point conversion is the same for BQ34Z100-G1 and BQ35100.

Sincerely,

Wyatt Keller

Hello Wyatt,

thank you for your detailed explanation. One more question:
What is the difference between OFFSET_CAL (0x0082) and CC_OFFSET (0x000A).

Thank you very much for your help.

Best regards

Stephanie

Hello Stephanie,

Both of these are defined in the TRM.

Sincerely,

Wyatt Keller

Hi, I have seen that. But it is not clear to me what that mean in Detail.

Best regards

Stephanie