Charging issue while Battery Voltage below 10V using LTC4162IUFD-LAD#PBF

Hi,

We are using LTC4162IUFD-LAD#PBF in one of our design and facing below issue

  • All most 10 % board don't pick charging if battery voltage below 10V, While same battery work fine on OK board.
  • Following is schematic of LTC4162. Here Capacitor C50 and C51 changed to 10uF/50V due to continues failure of 47uF/25V
  • Battery is 3*3.7V Lithium Ion Cell 4800mAH with protection circuit.
  • Input Voltage : 15.92V
  • Input Current : 0.13A

  • Battery Voltage : 10.04V

  • Battery Current : -1.00mA

  • Charger_state : battery_detection

  • Charger_status : charger_off

  • Battery Charge : 0%

  • Device Temperature : 27.87 Degree Celcius

Regards,

Mayank

    •  Analog Employees 
    on Oct 20, 2020 8:01 PM 1 month ago

    Hi Mayank,

    You mean it will not start charging on 10% of boards?

    Watch the battery detection on a scope. You will be able to see a voltage pulse on the battery node for about 1 second every 30 seconds. Can you send a plot of that? What voltage does it get to?

    It is possible the LTC4162 is being damaged (likely by hot-plugging inrush) and that damage prevents it from sourcing sufficient current during battery detection. See the attached guide on LTC4162 hot-plugging.

    PDF

    Regards,
    Zack