LTC6804 异常的GPIO1读数

我正在使用两片6804采集24节锂电池的电压和8个温度,然而每个芯片的GPIO1电压读数异常的高,高于其他通道和引脚电表读数1V。除此之外,还测得VREF2为3.6V左右,远高于说明书给的参数。每个温度采集通道使用的是100k热敏电阻和100k电阻分压的方式。

此外,采用同样的电路板监视4节锂电池,温度示数正常,但VREF2依然很高。

有没有可能是芯片或电路设计的问题呢?

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    •  Analog Employees 
    on Sep 10, 2021 7:24 PM

    GPIO1 can be affected by MUX shoot through glitches. The best workaround is to do a dummy conversion of just GPIO1 (don't bother with the read and it can be the fast filter mode), then do the GPIO conversions. Note that with un-buffered 100k sensors there can be long settling times and/or error from adc input current that should be considered. If a spare GPIO is available, it is also possible to not use GPIO1 at all.

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  • 0
    •  Analog Employees 
    on Sep 10, 2021 7:24 PM

    GPIO1 can be affected by MUX shoot through glitches. The best workaround is to do a dummy conversion of just GPIO1 (don't bother with the read and it can be the fast filter mode), then do the GPIO conversions. Note that with un-buffered 100k sensors there can be long settling times and/or error from adc input current that should be considered. If a spare GPIO is available, it is also possible to not use GPIO1 at all.

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