Hi Team,
Is there any problem in using the voltage applied to the CH port before the power supply voltage is applied?
Since it is used to monitor the remaining battery level, if you cannot use the above method, you need to consider another method.
The device is powered from a battery through a DCDC converter.
Best Regards,
Kenji
Kenji-san,
Generally, the input voltage should not be applied before the power supply is applied. If the input voltge is significantly higher than the supply of VA, then there may be damage to the device.
If you look at the Absolute Maximum Ratings, you can find that AINP or CHn to AGND should not be higher than 0.3V above the VA supply. If this is the case, then you may forward bias the input protection diodes used at these pins with high current and damage the structure. 
Joseph Wu
