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LED flasher 2 - This flasher moves, while lighting of LED drags on. The brightness of LED is four kinds, bright, less bright, almost dim and dim. These lighting states are moved with time. Control of brightness is performed in lighting time of LED like PWM (Pulse Width Modulation). There is no PWM function in PIC16F84A __ Designed by Seiichi Inoue
LED Flasher Checks Fiber-Optic Strands - 7-Jan-10 EDN-Design Ideas Send visible light through strands to check for breaks Design by Edwin A Mack, Port Republic, NJ
LED Flasher Indicates Low Battery Condition - 01/02/97 EDN-Design Ideas Many portable electronic devices could benefit from a visual indication when their battery requires replacement. Typical low-battery indicators simply turn on an LED when the battery voltage drops below a certain value. Such circuits actually accelerate the battery's extinction by drawing excessive current. The circuit in Figure 1 draws a mere 1 m A in its standby mode and averages only 20 m A when activated. The low current imposes a minimal burden on any battery circuit. An off-the-shelf, undervoltage sensor IC(IC1) monitors the battery voltage-- Design by David Johnson, DiscoverCircuits.com
LED Flasher needs only 1.5 VOLTS - 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 1.5 volt 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 . . . Hobby Circuit designed by David A. Johnson P.E.-June, 2000
LED Flasher that is Battery Free - 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 . . . Hobby Circuit designed by Dave Johnson P.E.-December, 2010
LED Flasher Universal 3v - The electronic 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 . . . Hobby Circuit designed by Dave Johnson P.E.-June, 2008
LED Flasher uses Minimal Parts - 11/20/97 EDN-Design Ideas A pair of alternating flashing LEDs makes an excellent visual alarm, this alternating LED flasher is based on one LED with built-in flashing function and two transistors driving or normal LED. Design by Dennis Eichenberg, Parma Heights, OH
LED flasher using NE555 timer IC - This circuit has a lot going for it. For one thing, it only consists of two transistors, two capacitors and four resistors. That also means it consumes very little power. You can control the flash rate by changing the size of the 100k resistors (100k makes for a pretty slow rate). You can also control the duty cycle by using resistors of different values on the two sides __ Designed by Colin Pringle
LED flasher with "Rising & Falling" Brightness - Here is a Simple Circuit to give a Flashing LED, With a "Rising and Falling" Brightness. It Uses the Sawtooth waveform from pins 2 and 6 to create the rise and fall. The Resistor and LED on Pin 3 are Optional. The 10K Potentiometer give a reasonable range of Speed. __ Designed by G.L. Chemelec
LED Flasher-Wig/Wag - This simple circuit will flash two LEDs in an alternating fashion . . . Hobby Circuit designed by Dave Johnson P.E.-December, 2004
LED Flasher-Wireless Circuit - When you would like to flash a LED through a thick plastic case without wires, use this hobby circuit. It performs this feat. It draws about 300ua of average current at 5v. It can be powered from a supply ranging from 3v to 6v . . . Hobby Circuit designed by David A. Johnson P.E.-January, 2011
LED Flashing Badge #1 - I have seen numerous flashing light badges at trade shows and conventions. They are often handed out as gifts to promote some business. The devices often use inefficient circuits, which cause the battery power source to be quickly depleted. . . Circuit by David A. Johnson P.E.-March, 2002
LED Flashing Badge #2 - This circuit uses a CD4013 dual D Flip/Flop IC. A single lithium battery will provide months of continuous LED flashing. It also has a tiny push-button switch to turn on and off the light flashing. . . Circuit by Dave Johnson P.E.-March, 2002
LED Flashing sweetheart kit - LED Flashing sweetheart kit __ Contact: Velleman USA
LED Lighthouse Flasher - This was originally designed for a model in a HO train set. It simulates the behavior of the light from a lighthouse. The LED intensity gradually increases, then flashes with a bright light and finally decreases slowly in intensity . . . Hobby Circuit designed by Dave Johnson P.E.-July, 2006
LED Lighthouse Flasher for HO Model Train - HO train sets often have authentic looking scale model homes and buildings. The hobby circuit below can be mounted inside a model lighthouse. The electronic circuit drives a single LED lamp in such a way that it produces light which simulates the rotation . . . Hobby Circuit designed by Dave Johnson P.E.-July, 2006
LED Modulations (2 versions) - Common Light Emitting Diodes (LEDs) require a DC forward bias current of 10 to 20 mA for proper operation. Typically the maximum DC current is 30 to 50 mA. The color of light (or wavelength λ) emitted from an LED depends on the semiconductor material used to fabricate the LED and this in turn determines the LED forward voltage at the operating current. __ Designed by M. Gallant
LED Musicolour: Light Up Your Music, Pt.1 - Now you can have a kaleidoscope of colour which continually changes in time to music. This consists of 16 strings of LEDs which are individually controlled by 16 frequency bands. Louder signals in each of those bands means that the respective LED string will be brighter. Use it for a Christmas light show, a disco or just for fun when playing music.__ SiliconChip
LED Musicolour: Light Up Your Music, Pt.2 - The new LED Musicolour makes building a spectacular light and music show easier than ever. In this second and final instalment, we explain how to build and test the unit and also detail how you can control it.__ SiliconChip
LED or Incadescent 12 Volt Lamp Fader - This circuit is similar to the "Fading Red Eyes" circuit (in the LED section) used to fade a pair of red LEDs. In this version, the lamps are faded by varying the duty cycle so that higher power incandescent lamps can be used without much power loss. The switching waveform is generated by comparing two linear ramps __ Designed by Bill Bowden
LED or Lamp Flasher - Minimum parts countingImproved version; 3V battery operation __ Contact: Flavio Dellepiane, fladello @ tin.it
LED or Lamp Pulser - Astonishing effect; 4.5V supply __ Contact: Flavio Dellepiane, fladello @ tin.it
LED Sequencer - The model 4017 integrated circuit is a CMOS
counter with ten output terminals. One of these ten terminals will be in a "high" state at any given time, with all others being "low, " giving a "one-of-ten" output sequence. If low-to-high voltage pulses are applied to the "clock" (Clk) terminal of the 4017, it will increment its count, forcing the next output into a "high" state __ Designed by © EETech Media, LLC.
LED Sequencer - This circuit is the essence of many "chaser" schemes that provide animation in advertising displays, lighting ten LEDs sequentially. __ Designed by Arthur Harrison
LED Solar Lantern Lights - Circuit of the LED solar lantern lights presented here is built around one 6V/1W Solar Panel (PhotoVoltaic Panel) and a 4V/800mAh Lead-Acid Battery. Here, commonly available 5mm White Straw Hat LEDs are used as the light source. how does the solar lantern circuit works DC 6V supply from the solar panel is fed to the __ Designed by T.K. Hareendran
LED Strings powered by AC Line - This shows 4 different ways to string white LEDs that are powered by a 120vac or 240vac power line. The circuit was designed by Ken Schultz . . . Hobby Circuit designed by David A. Johnson P.E.-December, 2004
LED Strobe - with high power led's available, their replacement for a xenon tube is viable! __ Contact: P. Townshend EduTek Ltd
LED Strobe & Contactless Tachometer - This versatile LED Strobe & Tachometer can be used to observe and measure the RPM of rotating machinery. It offers three different measurement methods and the readout is via a 2-line LCD module.__ SiliconChip
Led Strobe & Tacho Pt.2 - Last month, we published the circuit of our new LED Strobe & Tachometer and showed how to build the main unit and the strobe light. This month, we describe the assembly of the optional Photo-Interruptor and IR Reflector Amplifier boards. We also describe how the unit is used.__ SiliconChip
LED Strobe Flasher - This little circuit provides a surprisingly spectacular bright strobe flash which is adjustable with P1, the 200K trimmer potentiometer. P1, R1, R2, and C1 provide the flashrate. R1 sets the upper flashrate. The flashrate for the above circuit was measured at 12Vdc. If the supply voltage is steady or regulated, the flashrate is very stable. __ Designed by Tony van Roon VA3AVR
LED Strobe Has Independent Delay & Duration - 11-Jun-09 EDN-Design Ideas High-brightness LEDs, with independent delay and duration, find use in a visual-inspection application Design by Michael C Page, Chelmsford, MA
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