Hi S hengyue ,
Thank you for your attention to TI products! In order to solve your problem more effectively, I need to ask TI senior engineers who know more about this chip, and then answer for you. Once I get a reply, I will reply to you immediately.
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Hi
注意你如果要充电,需要用恒流设计,而非你现在的恒压。 你可以选择TI专门的充电芯片BQ系列(在电池论坛发帖选型)。用DC/DC也是可以的,毕竟充电BQ系列大多是降压,升压少。同时设计相对麻烦点,因为你要恒流设计,需要额外增加运放来做反馈,并且功能上也没有电池芯片专业。
按照你现在的电路,直接输出接大电容,相当于将输出短路,不烧才怪。