This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ25895: About BQ25895 and BQ25792

Part Number: BQ25895
Other Parts Discussed in Thread: , BQ25792

Hi, support team

My customer has the questions as follow:

About BQ25895:

1. When there is no Vbus input, if Vbat voltage is 3.0V, what is the voltage of Vsys?

2. When there is no Vbus input, Vbat is less than Vsys_ Min, there is no way to perform ADC sampling for Vbat (beyond the sampling range).
If I want to know the value of Vbat under such conditions, how to deal with it?

3. What is the difference between BQ25895 and BQ25895M?

About BQ25792:

1. When Vbat is 4.2V, the output of Vsys is 4.4V, and the working voltage range of my module is 3.5-4.35v, how to deal with it?
Or there is a better scheme (my application is: 1 lithium battery, charging current < = 3A, discharge current < = 5a)?


Thanks so much.

Best regards,
Yuki

  • Dear Yuki,

    Please open a separate thread to handle the BQ25895 questions.

    For the BQ25792, what is the desired battery voltage charge regulation? Assuming it is 4.2 V, the options would be to lower this charge regulation voltage or to step down the voltage from 4.4 V to the desired working voltage. Please keep the Minimum System Voltage above 3.5 V.

    Thanks,

    Mike Emanuel

    Please click "Resolved" if this answered your question.

  • In the manual, Vsys is 200mV higher than Vbat. Charging voltage is 4.2V, so Vsys is 4.4V, but my module is 3.5-4.35v, how do I do? Or is there is a better solutions?

  • Hello,

    As previously said, you can either lower the charge regulation voltage (to lower the VSYS voltage when the charge is terminated) or use a buck converter or linear circuit to achieve your needs based upon the application. This is for the case when the input is connected and the battery is fully charged.

    Please note, that if the input is not connected, VSYS will get its voltage from VBAT, meaning it will be lower than VBAT.

    Thanks,

    Mike Emanuel

    Please click "Resolved" if this answered your question.