• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

LED lighting

Status
Not open for further replies.

kalta

New Member
Hi.
I have very limited knowlege of electronics, and hope you don't mind me joining your forum to try and sort out a project I require.

I have done a hand cast of my daughters hand and have had it framed.
I would like to light the inside of the frame with 2 or 3 LED lights and want to run these off of batteries.

Would therefore appreciate any help or ideas you could give me.

Thanks kalta
 

audioguru

Well-Known Member
Most Helpful Member
Look at solar garden lights. They have a single dim LED running for about 6 hours from a battery cell. Three dim LEDs can be lighted for 2 hours.
Is that what you want?
 

audioguru

Well-Known Member
Most Helpful Member
3 alkaline cells produce 4.5V when new then the voltage quickly drops to 3.6V and drops slower to 3V. But white LEDs would dim when the voltage drops to 3.6V and turn off when the voltage drops lower.

If you use 4 alkaline cells that are 6v when new then the white LEDs will not dim much when their voltage quickly drops to 4.8V and will still be lighted when their voltage drops to 4V.

Each white LED needs to have its own series current-limiting resistor.
 

kpatz

New Member
You could use 4 NiMH cells (1.2V each) and get a nice steady 4.8V until the batteries are almost dead. Then you can recharge them and use them again and again.

You could get by with 2 cells using a buck-boost converter (this is how a lot of those solar garden lights work--they usually have 2 NiCd cells).

How bright do you want the LEDs? The brighter they are, the faster the batteries will drain.
 
Last edited:
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top