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BQ76952: 电流校准中的cc_gain计算值很小的问题

Part Number: BQ76952
Other Parts Discussed in Thread: BQSTUDIO

参考电流校准手册,cc_gain = (I_2 - I_1) / (cc2_counts_2 - cc2_counts_1)。实际中,I_1=0时,cc2_counts_1很小此处忽略不计,即可得到新公式 cc_gain = I_2  / cc2_counts_2,所以只需要1组数据即可计算出cc_gain的近似值,实际中EVSW(即bqstudio)的校准界面也是采用1个校准电流进行cc_gain校准的,如下图:

图中直接输入校准电流-2000mA,此时逻辑分析仪抓取0X91A8的cc_gain数据为 0x41726C9B,经过IEEE float转化得到值约为cc_gain = 15.15,此时逻辑分析仪抓取的READ_CAL1的cc2_counts数据为 0xffff796B(-34453),这个cc2_counts值是计算cc_gain = 15.15的原始数据。

请问这个原始数据cc2_counts = 0xffff796B(十进制-34453)是怎么得到的cc_gain=15.15?

备注:

<1>按照 cc_gain = I_2  / cc2_counts_2计算= -2000mA  /  -34453 = 0.058 远远小于15.15,是哪里出的问题?

<2>按照 cc_gain = (I_2 - I_1) / (cc2_counts_2 - cc2_counts_1) 计算的值同样远远小于正确的cc_gain值。