LTC4015 Charge voltage

Hello ADI experts,

I want to charge 8 series Li ion battery pack with LTC4015. I want to use 8 series Li ion battery so I need to 33.6 Volts  (When 18650 Li ion batteries are charged, their voltage can reach to 4.2V, 8x4.2V=33.6V)  but in the datasheet, Vin max voltage is 35 V. I have to work at the limits (If I am not wrong.), and LTC4015 is a buck battery charger.

 Won’t this case be a problem ?

 For example, for 33.6V charge voltage, VIN  voltage should be min >33.6V. Is this case  healthy or available?

 Can I adjust Vin for 33.6 V battery pack charge voltage? Is LTC4015 avaiable for 35V Vin – 33.6V charge voltage ?

Best wishes,

  • 0
    •  Analog Employees 
    on Apr 6, 2021 10:00 PM

    Right, you need VIN to be greater than the max battery charge voltage by a margin of at least 200mV (the differential drop-out voltage).

    35V VIN to charge a stack of 8 cells at 33.6V is a valid configuration. I recommend you operate as closely to 35V as you can.

    The LTC4015 has an VIN abs max of 40V. So, although we will not guarantee operation with VIN > 35V, the LTC4015 will also not be damaged unless VIN is >40V.