On 5/7/2012 3:19 PM, Ruben J=F6nsson wrote:
>> I built a similar circuit that had a diode between the solar panel and
>> the batteries so they wouldn't try to feed power back to the panel and
>> it worked great.
>>
> Would that be a problem? Is this bad for the panels?
>
> The original unit did not have any diodes in series with the battery

I have some of those solar powered lights as well except mine connect=20
the solar panel  to a NiCd battery, rated for 600mah.  The panels=20
themselves output 3.45V with a 680 ohm load resistor.  The board itself=20
is kind of interesting, they have a 4 leaded to-92 style part that=20
converts the battery voltage into enough voltage to run the LED lighting=20
using a switching design, the only other part on the board is the=20
inductor, looks like a small resistor.  The 4 leaded switcher contains=20
the diode and necessary hardware to control the charging and turn on/off=20
the light.

Overall the panels used in the lights I bought were extremely poor=20
quality . A better panel is the ones that Bgmicro has , they are encased=20
in epoxy like material and produce 4.5V @ 200ma and only cost $3 each,=20
seem to be much better quality.
http://www.bgmicro.com/PWR1241.aspx

Mark

--=20
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