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Solar powered yard light

I am trying to repair a solar yard light. The (blue) LED will not turn off and so the battery discharges. The original circuit uses a QX5251 device, with what I realize now is an inductor, to drive the blue LED with the 1-1/2v battery.

My first question concerns the original circuit. Stupid me replaced the battery installing it backwards.

Could that have destroyed the QX5251 or the inductor?

Maybe all I have to do is replace the inductor? I haven't been able to locate a non-Chinese source for the QX5251.

Then, I came across your solar rechargeable circuit and thought I would use it to replace the original circuit.

My questions now pertain to the resistors of your circuit.

Since my circuits voltage is 1.5v and yours is 4.5v do I need to decrease the resistor values proportionally?

Thanks in advance

Jerry C


  • It looks to me as though the QX5251 is protected against reverse connection on the battery, so that probably isn't the issue.  

    And, if your blue LED is lighting up (at all) with a 1.5 V battery, then both the IC and the inductor are likely working; it wouldn't otherwise.  If anything, I'd suspect the solar cell.
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