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DiscoverCircuits.com -- Hobby Corner
Last Updated on:
Tuesday, June 01, 2021 03:06 PM
Hobby Circuits List
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LINK to Dave's circuit, but DO NOT COPY any files to your WEB
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More
LED Circuits;
Flasher Circuit |
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No Battery LED Flasher |
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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. |
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Sales Coupon Flasher |
Sales Coupon Flasher |
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6v Solar Panel |
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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. |
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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. |
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Click on Circuit Below to view PDF of Schematic |
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