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I want to charge a 2-cell Li-ion battery with CN3722 charging IC. According to my circuit design, the float voltage at the battery terminal should be 8.4V. But, the float voltage is measured as 13.44V when input is of 15V. Also, when I connect the battery,it draws 220mA current for 1 second and after that it goes to 0A. Any idea, why this charging circuit is behaving like this?

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    \$\begingroup\$ There's something wrong with your schematic; there's a lot of junction "dots" missing. Can you confirm your circuit actually has these connections? \$\endgroup\$ Jan 29 '19 at 10:05
  • \$\begingroup\$ Yes, I have checked my schematic. The junctions dots are seems to be missing, but actually the lines are connected. All the components are connected according to the green lines, not as per as dots. Any other query? \$\endgroup\$
    – Aakash Dey
    Jan 29 '19 at 10:14
  • \$\begingroup\$ That is really surprisng, because this looks like Eagle, and Eagle really does these dots wherever there's a connection. But I believe you, but that means that the circuit you're looking at is not made as PCB etched from a layout done from this design within Eagle. Got a photo of the PCB as is? Maybe we'll spot a problem. A simple picture of the PCB design might help, too. \$\endgroup\$ Jan 29 '19 at 10:20
  • \$\begingroup\$ Single layer board file is attached. \$\endgroup\$
    – Aakash Dey
    Jan 29 '19 at 10:32
  • \$\begingroup\$ Hm, but that doesn't seem to have the same component numbering as the schematic – not really making this very easy. You don't happen to have the actual schematic used to make this layout? \$\endgroup\$ Jan 29 '19 at 10:46

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