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Member Since: March 2, 2010

Country: United States

  • I can’t work out how to calculate the power consumption of these boards, or rather - given say a coin cell battery of XXmaH, how many hours will it glow?
    I thought it would only last a few hours on a 48maH 3V battery, but it has been glowing for 11 days straight now, although it’s not as bright as it was the first days.

  • Will there be a breakout board for this? Pretty please?

  • Very cool! What is the weight?

  • Great project and very inspiring!
    I’ve been wanting to make a smaller lipo battery charger myself based on the 1555IC, but I’m a beginner in electronics.
    Would you like to share more details on the charger circuit board? Exact dimensions? Eagle files? etc…
    I’m mostly interested in charging 50-200maH batteries, would your design work for that.

  • Thanks Fred, great work!
    Would you like to share a circuit diagram and/or a picture of the connection between the solar cell and the Max 1555?
    Is the solar cell connected directly to the charger or are other components involved? I’ve read that solar cells are a bit tricky when it comes to balancing current and voltage…

  • I’m very interested in the solar powered charging part of the device. What solar cells was used? Trickle charge or “full charging”? Is there a circuit diagram or breakout board for this?