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Ten-LED Sequential Flasher using Low Powr - A while back I posted a flasher circuit which flashed 10 LEDs sequentially. That circuit was powered by four AA alkaline cells. The circuit below operates much the same way but has been modified to run from a single 3v CR2032 lithium coin cell. . . Circuit by Dave Johnson P.E.-April, 2011 Test Continuity with an LED - 01/06/11 EDN-Design Ideas Test circuits for resistance against a preset limit. [Design Ideas by Raju R Baddi, Raman Research Institute, Bangalore, India Design by Raju R Baddi, Raman Research Institute, Bangalore, India
Tester for Pulsed LEDs - This circuit is designed to test visible and infrared LEDs in pulsed mode operations. It can drive the LED with peak currents in excess of 10 amps. A light detector nearby can monitor the response time and intensity of the LED under test . . . Hobby Circuit designed by David Johnson P.E.-June, 2000
The Inexpensive Dimmable LED Desk Lamp - 30-Nov-12 -Design News: Andrew Morris designed a dimmable LED driver circuit that is simple and energy efficient. He then installed the circuit into a portable fluorescent lamp. __ Designed by Andrew R. Morris, Gadget Freak-Case #230
The LED Flasher - This is a very simple project using a printed circuit board and 8 components. It will flash an ordinary 3mm or 5mm (1/8" or 1/4") LED at a rate of about one flash per second. __ Designed by Collin Mitchell
The LED Flashing Sweetheart Kit - When was the last time you gave a gift you made yourself? Elementary school? Get off the consumerist fast track and quit copping out with inferior gifts like candy and flowers. The LED Flashing Sweetheart Kit contains a circuit board, 28 LEDs
The LM3410 LED Driver - The LM3410 IC is a constant current LED driver useful in either boost converter or SEPIC design applications. A SEPIC (Single Ended Primary Inductance Converter) design allows the power supply’s output voltage to be set above, below or equal to its input voltage. must register on this site __ Designed by Published in Elecktor July/Aug, 2010
The Ultimate Wireless Volume Control - 17-Aug-11 -Design News: Andrew Morris decided the usual wireless volume controls don’t offer enough functionality, so he created the ultimate volume control that connects between a computer or MP3 player and an amplified speaker system. __ Designed by Andrew R. Morris, Gadget Freak-Case #192
Thermometer with Four-Digit LED Display - Until recently, the Philips SAA1064 LED driver IC has been a sort of unofficial standard for driving seven-segment LED displays. It can be used to implement four-digit displays that can be driven over an I2C bus. must register on this site __ Designed by Published in Elecktor July/Aug, 2010
Three Flashing LED Doorbells - Battery Powered LED Circuits: These circuits combine a buzzer with one or more LED displays. When the push switch is operatedthe buzzer will sound and the LEDs will flash. When the switch is releasedthe buzzer will stopbut the LEDs will go on flashing for another 30 seconds or so. __ Designed by Ron J.
Three microcontroller ports drive 12 LEDs - 12/15/06 EDN-Design Ideas Engine tachometer uses few components and I/O lines Design by Nedjeljko Lekic and Zoran Mijanovic, University of Montenegro, Department of Electrical Engineering, Podgorica, Montenegro
Three pins, Three LEDs, Three buttons - 08/18/14 EDN-Design Ideas Many previous Design Ideas [1, 2] have shown how to use the Charlieplexing technique [3] to drive as many LEDs as possible with a minimum number of I/O lines. This Design Idea shows how you can drive three LEDs and scan three switches with only three I/O lines instead of six. Using the same principle, it will also be possible to manage four switches and two LEDs, or five LEDs and one switch Design by Francois AUGER & Philippe Fretaud
Three Volt Universal 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 . . . Hobby Circuit designed by David A. Johnson P.E.-June, 2008
Three-Channel White-LED Driver Uses Simple Circuit Step-Down DC/DC Converter - 09/13/12 EDN-Design Ideas Drive multiple LEDs with current mirrors from a single step-down converter. Design by Nora Jacalan Esteves, Technor Semiconductor LLC, Pleasanton, CA
Three-Colour Display using Bicolour LEDs - Transistors T1 through T20 form a grid to which common-cathode bicolour LEDs (LED1 through LED10) are connected. Transistors T1 through T10 have their collector terminals connected to the emitter of transistor...__ Electronics Projects for You
Three-Minute Closet Light - I have a coat closet by my front door. The thing is very dark at night and really needs some kind of illumination inside. I could hire an electrician to install a light in the closet ceiling and then wire it to a toggle switch outside the door but that would cost me quite a bit of money. . . Circuit by David Johnson P.E.-December, 2011
Three-Volt Low Battery Voltage Flasher - Many battery powered devices use two AA alkaline cells. Often you will not know when it is time to replace the batteries until the device powered by them actually stops operating. The hobby circuit below can be connected to a 3v battery, to give you some . . . Hobby Circuit designed by David A. Johnson P.E.-January, 1998
Three-Volt Powered Super Bright LED Flasher - I have posted several kinds of LED flashers over the years. This is yet one more flasher, designed to flash any high power LED of any color. It hits the LED with a 25ms 250ma pulse once every 2 seconds. This works out to an average current about 3ma. It . . . Hobby Circuit designed by David A. Johnson P.E.-April, 2009
Tiny Efficient High Power LED Camera Flash Solutions for Cell Phone Applications - Design Notes 231__ Linear Technology/Analog Devices
Tiny micro-controller driven lightshow using LEDs & a Picaxe 18A - Micro-controller driven LED displays are popping up everywhere nowadays, from shop windows, to tiny belly-button raver lights. However, most of these have a few problems. Firstly, the cheap ones are usually just that—so cheap that they are basically a throw-away item. Secondly, most of these lights are not programmable, so you are stuck with the basic program and sequence they are built with. This kit allows you to build a high-quality, fully programmable light display capable of producing any colour you desire.
Tiny Regulators Drive White LED Backlights - Design Notes 231__ Linear Technology/Analog Devices
Tool Shed LED Light - I have a lean-to 8ft by 12ft shed next to my house. It is full of lawn chemicals and garden supplies. There were times when I needed to get something from inside the shed during the dead of night. Early on I had to use a flashlight. But later, I installed a series of five 12v LED light strips on the ceiling. Each strip contained 15 3v white LEDs. The strip had 5 strings of three LEDs, wired in series, with a 150 ohm current limiting resistor. . . . Circuit by David Johnson P.E.-July, 2017
Torchs-LED - A LED torch is one of the simplest projects you can build and it's very interesting as it uses a super-bright white LED. In the history of LED production, red LEDs were the first to be invented and their output was so dim you could barely see if they were illuminated. You needed a darkened room to see them at all __ Contact: Collin Mitchell
Traffic Light - Our TRAFFICERGYR3 has many applications;. Mount the TRAFFICER on your toy train-tracks for signaling. Place TRAFFICER anywhere you’d like to draw attention and a smile. The unique small design will allow you to mount it almost anywhere. Operates with 9V battery, 12V car battery, four 1.5V batteries, or via one of our battery simulator kits. __ Contact: Kit from Elich Industrial Development, Corp
Transistor Flasher - The basic two-transistor flasher shown below has found its way into dozens of applications due to its simplicity and versatility. Applications have included such diverse circuits as a micropower low battery indicator, a lightning detector, . __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Transistor LED Flasher - A simple LED flasher that uses only two transistors, one capacitor and one resistor. This basic oscillator can have other simple applications. __ Designed by Jose Pino
Transistor LED flasher - 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
Transistors Drive LEDs to Light the Path - 01/06/11 EDN-Design Ideas Replace power-hungry incandescent bulbs with LEDs and reduce energy consumption. [Design Ideas by Eliot Johnston, Comnet International, Richardson, TX Design by Eliot Johnston, Comnet International, Richardson, TX |
