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

DiscoverCircuits.com, has 40,000+ electronic circuits, cross-referenced
into 500+ categories.    We have searched the web to help you find quick design ideas.
We make every effort to link to original material posted by the designer. 
Please let us if you would like us to link to or post your design.

HOME Schematics Index Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches

DiscoverCircuits.com -- Hobby Corner
Last Updated on: Thursday, November 16, 2017 06:32 AM

Hobby Circuits List

The contents & graphics of Discovercircuits.com are copyright protected.
LINKING to Dave's circuits is permitted but DO NOT COPY any files to your WEB SITE server

More  LED Circuits;   Flasher Circuit

No Battery LED Flasher

LED flashers have been used for a wide variety of applications.  Some flasher units have been used in food and hardware stores, to draw attention to sale items and are often attached to boxes which dispense product discount coupons. Typically, as the illustration below depicts, these simple units have a red LED, on each side of the housing.  Inside, is a battery and flasher circuit.  The housing also has space for rolls of preprinted sale coupons.  But, the batteries powering the flashing LEDs do have to be replaced every few months.  Since the flashing always occurs in well lit stores, there is almost always enough natural and artificial light available to power a flashing unit without using any batteries.  Instead of batteries, a small solar panel on top of the unit harvests enough energy to keep the unit flashing for as long as light is available.  A medium size super capacitor keeps the available voltage hovering around 5.6v.  This voltage allows the use of any LED color desired. I like the super bright green LEDs myself.
Sales Coupon Flasher   Sales Coupon Flasher
   
  6v Solar Panel  
Typical solar cells will produce about 400ua of current per square inch of surface area in usual store fluorescent light illumination.  A 5.6v zener diode limits the voltage to the super capacitor.
The circuit below is designed to flash two bright wide angle LEDs.  Energy needed to flash the light is drawn from the diffuse light available inside a commercial store.  A six volt solar panel on the top of the flasher assembly converts some of the light striking the solar cells to electricity which charges up a super capacitor.  The super capacitor supplies the peak current needed to flash the two LEDs. A constant current LED driver is used.  The two LEDs are wired in parallel. Each receives about 10ma of current, lasting 20ms. The flash rate is once per second.  The average current is therefore about 400ua.

Click on Drawing Below to view PDF version of Schematic

More  LED Circuits;   Flasher Circuit

Hobby Circuits List
eMail David A. Johnson, P.E. about this circuit


HOME Schematics Index Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches


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

Copyright  2002 - 2015 David A. Johnson & Associates.  All Rights reserved. 
 Linking is ALLOWED but COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED.