Post Go back to editing

C oder X termination

Category: Software
Product Number: LTC4015

Hello together and a happy new year,

I have a question about C or X termination with the LTC4015. I don't understand the information on calculating the threshold value of the charging current.

How should the following sentence be understood? „C_OVER_X_THRESHOLD uses the same format as IBAT“ 

Does this mean that the value is also given in amperes, or do I have to calculate the value using the IBAT formula (Battery current = [IBAT] • 1.46487µV/RSNSB) in addition to this formula? -> Current = C_OVER_X_THRESHOLD/(RSNSB • 21845.0/0.032V)

I am asking because I want to charge two battery packs one after the other and terminate the charging process of the LTC4015 with a threshold value of 100mA. And I want to set all timers of the charge controller to zero with "suspend_charger".

Of course, I can also do this by using IBAT, reading the value in my software, and carrying out the steps. However, I would like to use the C_over_X function.

I wrote the threshold value of 100mA in register 0x1C to 410 (0x019A). And, of course, I set the bit for en_c_over_x_term in register 0x29. Nevertheless, the controller continues to charge.
I read register 0x34 every second. However, the flag for c_over_x_term is not set.

Do you have any idea what the problem could be?

Thank you in advance

Edi

  • Hello together,

    I think my question has been answered. I found the section in the data sheet:

    I use the fixed settings provided by the Cell and Chem pins for a 4.2V/cell 4s Li-ion battery. If I understand correctly, C/X termination cannot be activated in this case.

    A brief answer, whether correct or completely wrong, would be great.

    Best regards.