Ultra Low
Current 3v LED Flasher #3 - This
circuit takes advantage of a tiny LMC7215 low current draw voltage comparator from National Semiconductor and a
super efficient green LED from King Bright. The 3v powered circuit forms a classic pulse generator circuit, which
drives the LED. The pulse width is set at about 20ms, the pulse rate is about 0. 5Hz and the peak LED current is
only 100ua . . . [Circuit by David A. Johnson P.E., 02/27/11]
Ultra Low Power LED Flasher - The efficiency of some newer LEDs is amazing. Some of the latest green
LEDs can launch blinding light with just one milliamp of current. I take advantage of one of these newer devices
in the circuit below. The flashing circuit uses a classic multivibrator . . . [Hobby Circuit designed by David A.
Johnson P.E., 12/21/08]
Universal Flasher Circuit - LED flasher with the LM3909 IC. . . . [Tony van Roon's circuit]
Universal Flasher Using a Latching
Relay - Latching relays are nifty
devices. Most contain two separate coils. When a voltage is applied to one coil the relay latches in one state
and stays in that state until voltage is applied to the unlatch coil. Since the latching and unlatching pulses
only . . . [Hobby Circuit designed by David Johnson P.E., 10/16/05]
Universal-3v-LED-Flasher - The
circuit below will flash any LED color with fixed current pulses powered by a 3v battery. It uses a charge pump
approach, which routes a constant current pulse through the LED, regardless of the LED voltage requirement. Using
this approach, white and . . . [Circuit by David A. Johnson P.E., 06/22/08]
Valentine Heart - 18 LEDs flash at three different rates and you can use these to create an
eye-catching Valentine Heart for that special person! A template for the heart shape can be downloaded. The
circuit is kept simple (and low cost) by using the 4060B IC which is a counter and oscillator (clock) in one
package. The circuit requires a 9V supply, such as a PP3 battery. . . [Designed by John Hewes]
Various LED Blinker Circuits - The circuit uses independent timers to flash two light emitting diodes.
Any time that light emitting diode D1 is lit__light emitting diode D2 will be switched off. Light emitting diode
D3 is on if both D1 and D2 are offCircuit for model railroad trains. . . . [from Rob Paisley's Model Train web
site]
Version A of 1.5v LED Flasher - To squeeze even more energy from a alkaline battery cell, this circuit
adds two transistors to a circuit similar to the above design to boost the efficiency. A small 1.5volt alkaline N
cell should flash the LED for a full year. It too uses a "charge pump" technique to provide a LED the needed
voltage . . . [Circuit by Dave Johnson P.E., 06/03/00]
Welch Scientific Model 2153C Stroboscope - Here is a schematic for a typical line operated variable rate
stroboscope. This unit is from Welch Scientific - Model 2153C Stroboscope. These things typically gather dust in
the dusty dark corners of high school physics labs. . . . [Written by Don Klipstein]
White
LED Array that is Lined Powered -
There has been a lot of excitement lately in the lighting industry. Some companies are beginning to manufacture
general lighting fixtures, which replace incandescent and fluorescent lamps, using LED lights. When proper heat
management is designed . . . [Hobby Circuit designed by Dave Johnson P.E., 02/28/10]
White LED Stroboscope With
Constant Duty Cycle & Constant Current Drive
- Finally, white LEDs are bright enough to use in a
practical stroboscope. This circuit can operate as a bench-top stroboscope that, in conjunction with an
oscilloscope or frequency meter and bench top power supply can accurately measure rotational speeds, or it can be
operated hand-held from a single 9V battery, . . . [From Dick Cappels' project pages]
White-LED
Driver Touts High Efficiency -
06/12/03 EDN Design Idea White LEDs, the most recent addition to the LCD backlight, find common use in
providing backlight for color LCDs. Thanks to their size and white-light output, they appear in small, portable
devices with color displays, such as PDAs. . . [by Dimitry Goder, Sipex Corp, San Jose, CA]
White-LED flasher operates from one cell - 05/26/05 EDN Design Idea 1. 5V circuit flashes white LED. . . [by
Anthony H Smith, Scitech, Biddenham, England]
Wig/Wag LED Flasher - This simple circuit will flash two LEDs in an alternating fashion . . .
[Circuit by Dave Johnson P.E., 12/18/04]
WINAMP and Disco Lights - Have you ever wanted to set up Disco Lights for your parties? DiscoLitez
could be the answer . . . [by Jim Fuller]
Wireless LED Flasher - There are times when you would like to flash a LED through a thick
plastic case without wires. The circuit below performs this feat. It can be powered from a supply ranging from 3v
to 6v. It draws about 300ua of average current at 5v . . . [Circuit by David A. Johnson P.E., 01/09/11]
Xenon Flash & Strobe Page - . . . [Don Klipstein's Web Site]
Xenon flash valve - An experiment of the xenon flash valve. . . . [The Electronic Lives
Manufacturing-presented by Chan]
Xenon Flasher - You are going to like this project. It costs less than $3.00, contains
six BUILDING BLOCKS, re-cycles a disposable flash camera and you are going to learn a lot about electronics.
Everyone has seen a disposable flash camera. . . . [Colin Mitchell]
Xenon Lamp Flash Detector
Amplifier - This circuit has a very
low standby current requirement yet has very high sensitivity toward the light flashes from a xenon lamp. When
connected to a flip/flop it can serve as an on on/off Controller . . . [Circuit by Dave Johnson P.E., 12/14/04]
Xenon Photoflash Controller - This 9v battery powered circuit is designed for remote control flash
needs. A charge control circuit turns off the high voltage generator when the photoflash capacitor is fully
charged. A neon lamp is included to indicate when the system is ready to flash . . . [Circuit by David A. Johnson
P.E., 06/03/00]
Xenon Strobe Light - A xenon flash tube is a triggered gas discharge device. A voltage may be
impressed across the tube and it will not conduct until the xenon gas is ionised by an external high voltage
(typically 3 to 5kV). Once triggered, the gas becomes a very low impedance, and discharges the storage capacitors
in about 1ms (this varies considerably, but this figure is fine for basic calculations) . . . [Rod Elliott
(ESP)]
Xenon Strobe Light - Disco anyone? Actually, this strobe serves a much more useful purpose
then making it look cool when you dance in the dark. You can use it to view fast moving objects, look for craks
in PC boards (hold the strobe on the trace side of the board and look from the component side) , and it is a
great attention getter in a store window. . . . [Design by Aaron Cake]
Xenon Strobe Light - The way that this circuit works is as follows. The AC line voltage is
rectified by D1 and D2 which connects to a voltage doubler circuit made up of the two 22uf capacitors. The Flash
Freq. Pot and the 10uf capacitor charge up which triggers the Diac. . . . [Circuit by Randy Linscott]
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