DIY Solar Powered Lamp
In this video I make a solar powered garden lamp from a regular mains powered lamp. The E27 socket is removed and a 1W LED is installed instead.
The circuit is analog and uses op-amps and transistors to control the charging of the battery, when to turn on the lights and when to cut out due to under charge on the lithium ion battery.
Check out the video above for more information.
In the video I design and test the circuit. You can find links to the PCB and schematic files below.
Remember to add the 3 jumper links marked in gray on the PCB overlay.
The Converter I used is not optimal, try to get one that has constant current as well :)
R8 500K to 6.8M ()
Q1 2N3904 (or similar)
Q2 BC328 (or similar)
Q3 2N3904 (or similar)
Q5 BC338 (or similar)
U1 LM324 Op-amp
D1 1N4007 (Any ~0.6Vf diode should be ok)
J2 LDR (Light Dependend Resistor)
J4 2x 6.3V Solar panels in parallel (I used 60*110mm from Ebay)
J1 18650 Lithium ion battery
J5 Switch mode converter + 1W LED (From Ebay "LM2596 DC-DC Buck Converter" - CONSTANT CURRENT IS RECOMMENDED)