Outdoor solar powered LED garden lamp / Tear down.

Welcome to our Forum, extension and content sharing platform of Electrical Test and Measurement Product Reviews Blog.

Registration this is Free, we accept contributors of 17 years old and above. We do not accept registration with Gmail

Active since 7 June 2012

Copyright Notice: Entire ITTSB.EU content & images they are copyright protected. - Forum search engine disabled to Guests - No need of you using Adblock software.

Kiriakos GR:
I just found today one of those single LED garden lamp, which I actually rescued it from becoming as permanent trash.

After a close inspection the only problem was that the battery was heavily discharged.
I was not aware that those lights are using AA NiMH, or even better I have never be interested to see what those devices hide under the hood.

The solar panel dimensions is 55 X 55mm, the voltage output with out load is 2V.
Even if similar ones on eBay it supposed be able to offer 60mA max, I am suspecting that this one it can give about 40mA as real power.
My measurements shown 1.30V at the battery side and 1.20V actual voltage at the LED side,
The circuitry draws 11mA from the battery and the LED 2.9mA, you are free to comment the efficiency factor of it. :)

The most interesting in this design is this ANA618 IC which works as battery controller.
What it does is to control the LED when there is no electricity coming from the solar panel.

The all concept is truly smart, as soon the panel is unable to deliver more than 200mV this event works as trigger and the IC activates the battery as power source and the LED.

Unfortunately I did not have a better luck from many others in the past, about locating the datasheet of the ANA 618.
What looks important is to be aware of the ultimate volts and current limits.
The single LED solution does not offer usable light, and so what comes next is the idea to do some tweaking on it.

Currently I am testing it with three LED in parallel. ;)

Enjoy the pictures.

Kiriakos GR:
Pictures set No3

An simple drawing about parts and connections.

ElectroElvis:
Very interesting terdown, I had one in past and when I took it apart was even more simplier. My solar panel had 4 contacts underneeth. When it was functional LED turned on when I covered panel with my hand, but there was no IC inside circuit, so I assume that 2 extra pins on solar panel were for some sort of light sensor.

Elvis

Kiriakos GR:
This little Solar device become a reason to me, for a close observation for about 10 Days.
Luckily I had a mixture of days with 100% clear sky and also few cloudy days.

Here is my conclusion summary in titles.

a) Those lights can fully recharge the inner battery only if they are placed in open space (garden) with out surrounding bindings or trees.
Alternatively they will function properly on a balcony which is facing south.
If the sun is blocked to them even for the half period of the day, those lamps are unable to operate.

b) At a cloudy day that the sky is 100% covered with clouds, those devices are unable to recharge.
By having a day that the sky haves openings on the clouds, equal to 60% Clouds & 40% clear sky, the lamp managed to get 80% of charge.

c) The offered light from the lamp is so few (single LED designs) that honestly they do not have a practical use at all.
The very cheap versions of those lamps is just a decorative toy, which needs the climate of South Europe to support it functionality.