This is an updated post regarding my 4S arduino based lithium ion balance management system (BMS).
- Replaced external voltage reference to a more stable one. Upgraded to a REF3012AIDBZT from Texas instrument. This does not require an output capacitor for stability.
- Modified Buck converter RT6208GE. Grounded pin 4 to set the max peak current to 50mA which is an average current of 25mA. This was done to eliminate audible oscillation from the buck converter
- Increased copper traces for ADC pins A0-A3
- Better layout to increase continuous copper plane on internal layer
updated 01/13/2019: For the new arduino version, load bootloader with 8MHz clock. I did more testing and this was more stable and accurate on the adc then the 1MHz clock setting.
I will be doing testing on these new versions and see how they perform. I will post results as soon as I can. Also below I will attach all files needed (schematics, gerber, bom) if you wish to make your own.
updated 01/13/2019: Download arduino code version A15.