Electronic Circuits and electronic circuits, electronic schematics plus an extensive resource for hobbyists, inventors and engineers

DiscoverCircuits.com, has 45,000+ electronic circuits, cross-referenced into 500+ categories.
We have searched the web to help you find quick solutions & design ideas.

Got Designs?
Please eMail
if you want me to link to and/or post your original design
NOTE:  We make every effort to link to original material posted by the designer. 
Please contact us if our link is not to your site!  Thanks.

Circuit Solutions Notebook
Last Updated On:  Wednesday June 02, 2021

Latest Technical Challenge           Previous Circuits Solutions           Circuit Solutions in Progress


30 LED Night-Light


Design an efficient long life night-light, using up to 30 white LEDs



The circuit solution below uses capacitor to limit the current through a series-parallel string of 30 LEDs.15 LEDs are wired in series in one direction and 15 more in the other direction. The capacitor limits the average current to about 20ma. The 100 ohm metal oxide resistor acts as a fuse.  As the sketch below depicts, perhaps the final product would have three clusters of 10 LEDs on three sides of plastic block, which would plug into the 120vac outlet.  They might be angled slightly inward toward the wall, so light would spill onto the wall behind the device.  With quality white LEDs the device should last for 10 or more years.


30 LED NITE LITE David A. Johnson, P.E., October 27, 2005




HOME Schematics Index Hobby Corner Dave's Circuits Contact Info
Imagineering Ezine Dave Johnson, P.E. Faraday Touch Switches

 About Us   |  Advertise on DiscoverCircuits.com   |   Report Broken Links  |   Link to DiscoverCircuits.com  |  Privacy Policy

Copyright  January, 1998 - June, 2021     David A. Johnson  All Rights reserved. 

 COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED!