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BQ25890: bq25890 new design HW connection problem

Part Number: BQ25890

Hi,

I am designing a battery charger circuit with BQ25890, here I get some questions about circuit connections, could you please me?

1. If USB function is not needed, can I leave D+, D- and DSEL pins unconnected?

2. If QON(Pin12)function unused, can I leave this pin unconnected?

3. Do I need other pins connection for this IC to MCU communication except SCL, SDA and INT pins?

  • Hi,

    Regarding 1, you can leave DSEL unconnected.  I recommend tying D+ = D-, which sets the internal IINDPM register to maximum value.  You can use ILIM to clamp input current limit to lower value if desired.

    Regarding 2, /QON can be left floating as it has internal pull up.

    Regarding 3, SCL and SDA and INT are the only required pins for host control.  If you don't need OTG, then it can be tied to ground.  It might helpful to use GPIO to control /CE and enable/disable charge through software.