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Heart of LEDs - Here is a fun project that you can give to that "someone special". How about Mother's Day or did you forget St Valentine's Day?. __ Designed by © Grantronics Pty Ltd High Current Pulsed LED - Just to Play withBut it Might have some Practical Applications __ Designed by G.L. Chemelec
High Efficiency 12V White LED Driver - DC powered LED lighting circuits can vary from trivial single LEDs with series resistors and LEDs with simple analog current regulators to more complicated switching power supply circuits such as this project. There is a tradeoff between simplicity and circuit capabilities. This more complex circuit adds features such as regulated light level across a wide range of input voltages and automatic circuit shutoff on low input voltage. __ Designed by G. Forrest Cook
High Efficiency ThinSOT White LED Driver Features Internal Switch & Schottky Diode - DN325 Design Notes__ Linear Technology/Analog Devices
High Efficiency White LED Driver Guarantees Matching LED Brightness - DN267 Design Notes__ Linear Technology/Analog Devices
High Efficienty ThinSOT White LED Driver Feature Switche & Schottky Diode - Magazine Design idea
May 2004__ Linear Technology/Analog Devices
High Efficienty White LED Driver Guarantees Matching LED Brightness - Design Notes 267__ Linear Technology/Analog Devices
High Intensity Line Powered LED Flasher - There are times when you would like to generate an intensely bright flash of light using electrical power from the AC line. The circuit below can drive a one to three watt power LED with about 350ma of peak current. Since the circuit drives the LED with . . . Circuit by Dave Johnson P.E.-December 07, 2008
High Power Flashing LED - The circuit converts an off-the-shelf solar powered LED path light from producing a steady state light to one that produces a flash. This circuit includes a tiny dual Schmitt trigger inverter IC which form the pulse generator and the daylight sensor circuit . . . Dave Johnson, Lubbock TX-DC Magazine - Issue 7 Mar 2010
High Power LED Flasher - Power LEDs are becoming more popular these days. The DC input power to these devices ranges from 1 watt to 5 watts. Normal LEDs only receive about 0. 05 watts. At this higher power, these devices can emit a lot of light . . . Dave Johnson, Lubbock TX (Aug 10, 2008)-DC Magazine - Issue 7 Mar 2010
High power LED flashlight - Using a Cree LED, homemade lens, rechargeable batteries, two regulated power levels, and electronic switching. __ Designed by Manfred Mornhinweg
High Power LED Mood Lamp - in this page we will introduce a great project designed by Toon Beerten. His project named "DIY LED Mood Lamp" can become a very interesting add-on for your room that's absolutely sure it will impress everyone. As you can see on the photos, we talk about a color fading lamp, that looks amazing! __ Designed by Toon Beerten
High Power LED Stroboscope - Stroboscope is a convenient and accurate enough instrument to measure speeds of rotating objects in homes or industries. One can use it to find the speed of fans, motors or any other rotating object. It is a flashing light that provides sharp light pulses at a variable rate. An object rotating with frequency matching the pulsed light is observed as stationary__ Electronics Projects for You
High-power LED drivers require no external switches - 07/19/07 EDN Design Ideas: Suiting a variety of applications, these circuits transform a switching regulator into a current source for driving power LEDs Design by Alfredo H Saab and Steve Logan, Maxim Integrated Products, Sunnyvale, CA
High-Power_Flashing_LED - The circuit converts an off-the-shelf solar powered LED path light from producing a steady state light to one that produces a flash. This circuit includes a tiny dual Schmitt trigger inverter IC which form the pulse generator and the daylight sensor circuit . . . Dave Johnson, Lubbock TX-DC Magazine - Issue 7 Mar 2010
High-side current-sensing switched-mode regulator provides constant-current LED drive - 04/14/05 EDN Design Ideas: Many suitable circuits exist for driving LEDs in constant-current mode and from low-voltage sources. For example, references 1, 2, and 3 show circuits that use switched-mode-regulator ICs and low-voltage sources to supply LED current. Design by Bradley Albing, Philips Medical Systems Inc, Cleveland, OH
HO Model Train Lighthouse Flasher - 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 David A. Johnson P.E.-July 11, 2006
HO Train Lighthouse Flasher Revisited - HO train sets often have authentic looking scale model homes and buildings. A while back someone asked me to design a flashing LED light, which he could mount inside a model lighthouse and have it operate so it would appear to rotate and flash. I designed a working circuit but I was never pleased with the results. i’m still not 100% pleased but the revised circuit below seems to operate a bit better than the older circuit. … [Hobby Circuit designed by Dave Johnson P. E. , May 2012] . . . Hobby Circuit designed by Dave Johnson P.E.-December 24, 2012
Hot AC Power Line Indicator - The circuit below is designed to detect when a power cable is active (hot). When the flat sensor end of the device is held near an active AC line, the bright green LED on the top of the housing will glow. It is powered by a 3v CR2032 lithium coin cell. I . . . Hobby Circuit designed by David A. Johnson P.E.-May 02, 2005
How to Control LED Brightness with a PWM using a 74AC14 - We now have a simple circuit for generating variable duty-cycle pulse-width modulation. The next two pages are devoted to practical applications of connecting the PWM to an electronic component. For testing purposes, it is best to start with a safe, small, and simple load. We'll start by adjusting the brightness of a single LED with a pulse-width modulated wave. __ Contact David Cook
How to Control Multiple Leds - Multiplexing the i/O ports, you can control many LEDs using a few ports. __ Designed by Jose Pino
IC Controlled Emergency Light with Charger - White LEDs are replacing the conventional incandescent and fluorescent bulbs due to their high power efficiency and low operating voltage. These can be utilised optimally for emergency lamp and vehicle turning__ Electronics Projects for You
ICL7107-DigitAL LED AM METER - Ammeter is a great addition to any Laboratory Power Supply as it will measure the current consumption and help you determine if there are any problems with the circuit that you are building or testing. This amper meter is capable of measuring the current consumption up to 10A with selected 100mA, 10mA and 1mA accuracy. __
ICL7107-DigitAL LED VOLTMETER - This digital voltmeter is ideal to use for measuring the output voltage of your DC power supply. It includes a 3.5-digit LED display with a negative voltage indicator. It measures DC voltages from 0 to 199.9V with a resolution of 0.1V. __
Illuminated Banister - The remote capacitance sensor circuit is placed inside a small potting shell, which contained a three screw terminal block and a single turn variable resistor. The variable resistor allowed the capacitance needed to activate the switch to be set from about 10pf to 170pF.
. . . Dave Johnson, Lubbock TX-DC Magazines - 2nd Q 2012
Improved Optocouplers Reduce Current Draw, Resist LED Aging - 14-Dec-07 EDN Design Ideas: With improved optocoupler circuits, you can enhance the accuracy of zero-voltage sensing Design by Peter Demchenko, Vilnius, Lithuania
Improved Solar LED Spot Light - Nearly all the Chinese made solar powered LED lights I see being sold at Lowe's and Home Depot home improvement centers are poorly designed. Their solar panels and battery packs are all undersized. The light from their Chinese made LEDs fade rapidly and the devices never make it through a complete night before the light dies . . . Circuit by David Johnson P.E.-February 03, 2013
Increase Efficiency In Embedded Digital-I/O Lines - 04/21/11 EDN Design Ideas: Multiplex iO lines and drive LEDs without ghosting. Digital-i/O-multiplexing techniques, such as “Charlieplexing” or “Gugaplexing, ” let an eight-digit, seven-segment LED display connect to nine i/O pins of a microcontroller (references 1 and 2). These methods use lower-duty-cycle timing, which requires a driver between the microcontroller’s i/O lines and the display to achieve good visibility. The circuit in Figure 1 uses an 8+N/2 i/O bus for interfacing an N-digit display and as many as eight buttons on the same bus. This method needs no driver. You can apply it to any programmable device with LED-driving capabilities, such as small PIC or Atmel microcontrollers.
__ Circuit Design by Vasile Surducan and Emanoil Surducan, National Institute for R&D of Isotopic and Molecular Technologies, Cluj-Napoca, Romania
Increased power for LED Flasher - Power LEDs are becoming more popular these days. The DC input power to these devices ranges from 1 watt to 5 watts. Normal LEDs only receive about 0. 05 watts. At this higher power, these devices can emit a lot of light . . . Hobby Circuit designed by Dave Johnson P.E.-8/0/2008
Indicates 120 VAC or 240 VAC - Two LEDs indicate if a power line has 120vac or 240vac voltage on it . . . Hobby Circuit designed by David A. Johnson P.E.-July 09, 2006
Indicates Battery Charge Current - This circuit turns on a LED whenever it detects at least 25ma of battery charge current . . . Hobby Circuit designed by David Johnson P.E.-July 23, 2006
Inductive Pulse Receiver (175Khz) - This circuit is discussed in more detail in the Experimenters Journal. The receiver’s six inch diameter coil detects the ring signal from the above transmitter and use a single NPN transistor to provided enough amplification for the signal to be easily viewed on an oscilloscope . . . Hobby Circuit designed by David A. Johnson P.E.-July 09, 2006
Inexpensive LED Drives Flash & Beep - 06/05/97 EDN Design Ideas: Sometimes, you need an alarm that is both audible and visible in an application that's stingy with space, power, and budget. The circuit in Figure 1a is compact, efficient, and inexpensive. The F336HD flashing LED (part no. 276-036 at Radio Shack) is a useful device. It operates directly from 5V and produces a consistent pulse of light at approximately 1 Hz without a time-constant capacitor. Design by Dennis Eichenberg, Parma Heights, OH
IR Remote Control Tester - Gadget Freak Case 147:Couch potatoes should be particularly interested in Bill Bowden's remote control IR receiver, which allows users to control the power of virtually any electrical appliance (including those not equipped for remote) using their standard remote control. It's based on an IR receiver circuit, __ Designed by Bill Bowden
IR Remote Control Tester - This is a fairly easy circuit that can be used to test TV and VCR remote controls. The infrared detector module (GP1U52X) (Radio Shack 276-137) produces a 5 volt TTL pulse train corresponding to the digital code of the particular remote control key pressed. In the lower circuit, the module output is normally low with no signal received and becomes a positive going pulse train when a signal is present __ Designed by Bill Bowden
IR Remote LED Indicator Light - There are times when you would like to transmit a signal from one LED indicator light to second LED at another location. The circuit below works well for this application. It takes advantage of the fact that the internal infrared LED inside an opto-isolator . . . Circuit by Dave Johnson P.E.-December 26, 2008 |
