EVAL-L9963-NDS Coulomb Counting Routine

[APal.2]

Hello,

I am currently working on an electric go-kart project . For the BMS I use L9963-NDS paired with an external MCU ( STM32F411VE) via SPI ( non-isolated). For the project I use a battery with 4 cells with approximately 16 V and a resistor of 1000 Ohms for the cell current reading. I have to point that the reading is done from one of the cells .

The problem I ran into is with the Cell Current Measurement / Coulomb Counter Routine. I gave a command using single write access to enable CoulombCounter_en bit from CSA_GPIO_MSK register and I read the responses from the 0x7B and 0x78 command feedback . However , there is no reading of the cell current from 0x7B and from 0x78 static wrong value ,stays the same .The CoCouOvf bit toggles continuously ,as well as sense_plus_open and sense_minus_open bits . From the datasheet I understand that in case of register overflow it will saturate CoulombCntTime to 0XFFFF. Also , I did not set up any threshold currently . It can be a software related issue or a hardware related issue ?

I have attached two pictures with the Live Expressions for the visualization.

[KTANG.9]

Hi,

Please follow current sense guidelines in the datasheet, especially for RSENSE.

Current Sense / Coulomb counting is valid only when there is a LOAD in the circuit ( such as a motor / light )