BQ25710: In AC only mode Vsys Voltage drop

您好，

已经收到了您的案例，调查需要些时间，感谢您的耐心等待。

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从能源的角度来看,这是可以预料的。 当系统消耗的电流超过适配器所能提供的电流时，系统电压将会降低。 我的建议是使用PROCHOT通知CPU在引导过程中减少负载。 您可能需要将CELL_BATPRESZ针脚拉低电平以指示电池取出。

1）I have verified that the CELL_BATPRESZ pin voltage is approximately 3.3V when the battery is not inserted. Does this comply with the design requirements? The specification document mentions that the 3-cell battery requires 55% of VDDA.  （VDDA is 6V）
2）Additionally, I have attempted to adjust the ‌Tmax value‌ to shorten the duration of the ‌Ilimt1 current limit‌ during high-load conditions, aiming to prevent ‌Vsys voltage drop‌. However, no improvement was observed. I also tried setting ‌Tovld = Tmax‌, allowing the adapter (Vbus) to handle transient high current during sudden load surges, thereby theoretically stabilizing Vsys. Is this logic correct? If yes, why did it fail to improve the situation? Theoretically, this should work.

您好

1.TI建议在拆卸电池时拉下CELL_BATPRESZ引脚。
2.是的，您可以使用峰值功率模式来支持系统负载。或者，您可以提高电流限制（IINHOST）。我认为你不能让TOVLD=TMAX。确保在VSYS上启用PKPWR触发器（EN_PKPWR_VSYS=1和EN_IDPM=1）。

Thank you for your response. I'd like to ask:

1. What different behaviors would the Charger IC exhibit when the CELL_BATPRESZ pin is pulled low versus not pulled low in the absence of a battery?

2. What is the correct connection method for the CELL_BATPRESZ pin? Our current configuration uses an 82KΩ pull-up resistor to VDDA and a 100KΩ pull-down resistor to GND. In Adapter-only mode when the battery is removed, does this pin require the EC to actively control pulling it low?

3. Since we are currently using a 100W adapter, the IIN_HOST setting has already reached its limit. I attempted to use Peak Power Mode, but observed that after exceeding Tovld, the VBUS current is limited at the Ilimt1 level for the duration of Tmax minus Tovld, yet VSYS still drops significantly. Is there a Prochot trigger setting specifically for VSYS in Adapter-only mode? The datasheet mentions VSYS-related Prochot configurations, but these appear to target Battery-only mode. Does Prochot also trigger when VSYS drops in Adapter-only mode?

4. Could you explain what the following terms in the diagram mean: PP_ICRIT, PP_INOM, PP_IDCHG, PP_VSYS, PP_VDPM, PP_BATPRES, PP_CMP, PP_ACOK? How are they defined? Additionally, what is the difference between PP_ICRIT and the "ICRIT" labeled in the diagram? If "ICRIT" is a configuration setting, what does "PP_ICRIT" represent?
5. 

您好

It look like the customer has many questions about this part. My suggestion is to order a BQ25710EVM and follow the EVM user guide, at the same time reviewing the datasheet. 

This will be the quick way to get the questions answered.