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BQ25887: BQ25887 ADC register read

Part Number: BQ25887


My name is Babu, 

I have connected the input supply as adapter source and I am unable to read the values of ADC registers even after enabling the functions of the ADC, can you help me out regarding this?

The layout and schematic of my pcb is:


  • Hi Babu,

    You can see tips for schematics and pcb layout for the BQ25887 here: Layout Tips

    Namely, I recommend wider vias for VBUS and BAT pins. Additionally a ground plane polygon pour would do a better job of maintaining all grounds at the same level, dissipating heat, and minimizing EMI and noise on I2C lines. Additionally I recommend placing the PMID and REGN caps as close to the pins as you can, and this is recommended for the other various capacitors around the device as well. A polygon ground plane might be helpful in that regard.

    As for the ADC, can what voltage are VBUS and BAT when you attempt to enable the ADC. Can you please readback the ADC Control register after you enable the ADC to confirm that it remains enabled and the bit does not return to 0 after writing to it?

    Best Regards,

    Juan Ospina

  • Yes Actually I can read back ADC values and my problem is resolved now, thanks for your response Juan , please help me regarding the PMID post of EVM which I have posted there