TI中文支持网Part Number:BQ27546-G1
保护板输出端短路时候，用示波器监测电池两端电压，发现电池两端的电压在短路过程中，有很高电压脉冲，会高于bq27546 的电压。我想在bq27546 电源输入加一个RC 滤波，怎样一个参数合适呢？
Star Xu：
您好，由于问题比较复杂，我需要询问更了解这款芯片的TI工程师，再帮您解答，稍后回复
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lei tang：
补充一下，是否帮可以帮忙评估一下，在电量计供电前加一个R电阻滤波如下图，如 R为100欧姆。这个电阻会影响电量计的精度么，若不影响此电阻最大可以加到多大？
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Star Xu：
您好，请参考下面的内容
From the wave form, the overshooting surpasses 5.5v, the maximum voltage limit at it power input, using higher cap at power and BAT input should always be good.
But one more thing to pay attention to is the voltage on SRP and SRN during short test, the negative voltage threshold for these pins are only -0.3v, so add two schottky diodes in parallel between SRP and SRN can be tried(the 2 diodes shall not be in same direction, neither be in back to back, the anode of one diode should be connected the cathode of another diode so as to clamp the voltage low enough), also please not the Vss and SRP should be tied together to a single point, in case the voltage across this two pins surpasses the limit.
Also the Vss and Cell- shall be connected to a single point, and the Cell- to Vss star like connection point shall be as short as possible.
详细请参考下面帖子内容。
e2e.ti.com/…/bq27546-g1-bq27546-g1-broken-after-short-test
