Inside the example i deconstructed was a single 1 25 volt 100 mah aaa nicd cell and a small pcb with the led a 220 uh inductor and a four pin voltage boosting integrated circuit marked yx8018.
Led solar lawn lamp driver ic.
To run a led from single 1 5 v 1 2v or in particular largely depleted batteries the famous joule thief circuit using a coiled toroid is great.
While the last circuit works well for driving a yellow or red led it runs at 2 4 v the output of the nimh battery it does not have sufficient voltage to drive a blue or white output led.
Using the solar light ic all you need is the solar ic an inductor and the ultra bright led to make the circuit.
During day time the internal rechargeable 6 volt sla battery receives charging current from the connected solar panel through polariy protection diode d9 and current limiting resistor r10.
The solar lawn lamp mainly uses the energy of the solar cell to work.
However when salvaging the solar cell and battery from a cheap solar garden light to make a charging circuit i realised the electronics are in fact a simple led driver.
Solar light ics are very handy they have the dark detection circuit and the voltage multiplying led driver built into one small four pin component.
It requires only an external inductor to construct a boost power supply with over 90 per cent efficiency.
Solar garden light circuit.
The yx8018 comes in a 4 pin transistor style to 94 package and the pin.
It boosts 0 8 2v to drive white leds or other colors with 85 90 efficency.
You can make your own solar light or single battery led booster driver.
A solar garden light circuit.
Add the battery and the solar cell and you have a solar light.
Ana608 is the core component of all solar garden lights.
This outdoor led solar garden lights project is a hobby circuit of an automatic garden light using a ldr and 6v 5w solar panel.
It offers the advantages of low power dissipation low minimum operating voltage and automatic dusk to dawn switching.
The complete circuit is shown in figure 2.