To calibrate new or refilled BQ20Zxx chips (Step1) you must to follow instructions below. If you don't replace or refill the chip just enter the values needed in Step2 window and press Calibrate button.
Don't forget to start Impedance Tracking after calibration .
To calibrate new or refilled BQ20Zxx chips you must to have constant power source and constant electronics load. We recommend to use load based on LM317:
Generally the process flow is the follow:
- Replace cells with 470 ohms resistors.
- Connect power source. Ground must be connected to battery ground terminal for sence resistor to be included into circuit. Positive must be connected to most positive point of cells pack.
Alternative method: Connect cells and connect constant power source to cells pack "-" and battery terminal "-". Set current limit to 1.5-2.0 A. Turn the power ON when prompted to connect load.
- Read battery data.
- If battery data is OK then read device Data Flash.
- After Data Flash reading is complete then press Calibrate button.
- Follow the wizard.
Now the chip is ready for usage. Remove resistors, connect cells and start Impedance Track algorithm.
Perform calibration cycles. It's very important coz battery will learn its capacity and update impedance table at this step.
- Fully charge the battery.
- Let it relax for 2 hours.
- Discharge the battery with the current that is normal for your laptop. Let's say it's 1500mA.
- Let it relax for 5 hours.
- Charge the battery.
- Check MaxError value. If calibration is OK the value must be 1% If not then repeat the cycle.
For better accuracy Chemistry ID of your cells must match the Chemistry ID of Data Flash.