Dear Sir
I have a customer use BQ2000 to charge 3S Ni-MH Battery. I suggest them follow up our BQ2000EVM design. Customer design charge current as 0.1~0.2A so the R-sense resistor setting as 0.5R. Customer reduce Power Inductor to 10uH. I check all wave, Phase Node, Mode pin, every thing is okey at fast charge mode (CC Mode). When charge done, There is a spike current around 5.5A to Battery Cells.
I Change indcutor to 100uH (same as our BQ2000EVM). When charge done, There is not any a spike current to Battery Cells.
Did BQ2000 need a high value of power inductor? What's BQ2000 doing when charge done?
I can not analize from Buck topology. My cusotmer want to a reasonable explain. Would you please give a hand?
I catch some wavefrom. If you want , I can email waveform to you.
