|
Ramping Lamp Driver - This circuit drives any 12v lamp, incandescent or LED type, in a ramping fashion. Each press of the button toggles the lamp from a fully off mode to a fully on mode. But, instead of an instantaneous lamp intensity change, the power is slowly ramped up a . . . Hobby Circuit designed by David A. Johnson P.E.-December, 2007 Ramping LED Driver - The circuit below was designed to drive a LED with an intensity ramping mode. Two 555 timers generate two different triangle waveforms. The upper device generates a 10KHz signal while the lower unit produces a 1Hz signal. The two signals are fed to a. . . Circuit by David Johnson P.E.-December, 2007
Random' Flasher for 8 LEDs - This project uses a 4026 counter and display driver IC to flash eight LEDs in an apparently random manner. It can be used to create a display of your choice. __ Designed by John Hewes
Really Bright 10W LED Floodlight - Light level rivals halogensat MUCH less power!__ SiliconChip
Rechargeable Torch Based On White Led - Rechargeable torches don’t come without problems. You need to replace the bulbs and charge the batteries frequently. The average incandescent light-emitting diode (LED) based torch, for instance, consumes around 2 watts....__ Electronics Projects for You
Red LEDs Function as Light Sensors - 03/20/08 EDN-Design Idea You can build simple LED illuminators using the red LED to sense ambient-light level Design by Geoff Nicholls, Glinde, Germany
Reduced Power Sequential LED Flasher - The 74HC4017 is a neat decade counter which has 10 decoded outputs. When supplied with a low frequency clock and with a LED attached to each of the outputs, an interesting ten step sequential flasher effect can be produced. The LEDs can be configured in . . . Hobby Circuit designed by David Johnson P.E.-November, 2008
Regulated 12V Dual LED Lamp - This is an ultra-simple LED spot lamp that consists of two LEDs and a current regulator circuit. It is designed for use in 12V solar powered lighting applications and can be used in cars, boats, RVs and even fountains. Only seven components are required. The circuit produces non-flickering regulated light with an input of 11 to 20 volts. If the lamp is potted in Silicone caulk, it will be completely waterproof. The circuit will support either 20mA, 25mA and 30mA LEDs by changing the value of one resistor. __ Designed by G. Forrest Cook
Regulated 24 Watt Broad Spectrum LED Lamp - ultra-bright __ Designed by G. Forrest Cook
Regulated Dual 3 Watt White LED Lamp - Simple, reliable regulated night light __ Designed by G. Forrest Cook
Regulated Dual White LED Lamp - This is an ultra-simple LED spot lamp that consists of two LEDs and a current regulator circuit. It is designed for use in 12V solar powered lighting applications and can be used in cars, boats, RVs and even fountains. Only seven components are required. The circuit produces non-flickering regulated light with an input of 11 to 20 volts. If the lamp is potted in Silicone caulk, it will be completely waterproof. The circuit will support either 20mA, 25mA and 30mA LEDs by changing the value of one resistor. __ Designed by G. Forrest Cook
Remote LED Annunciator - IN THE BAD OLD DAYS, anyone rolling up at a department-store deli to buy a few slices of salami or whatever had to muscle their way through the crowd and try to attract the attention of a salesperson or they’d never get served. It was much the same at employment offices and medical scanning departments, where the rudest and most obnoxious people were often attended to first.__ SiliconChip
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, 2008
Remote Solar LED light - I created this circuit in an attempt to make the simplest possible solar powered project. It would make for an excellent science fair project, and would also serve as a good introduction to solar powered circuitry. It may also have some practical uses, such as shedding some light into a dark part of your house. The idea is simple, the solar panel converts sunlight into a trickle of electricity. The electricity is used to run a white LED __ Designed by G. Forrest Cook
Revisited-Model Train 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 David A. Johnson P.E.-July, 2006
RF signal meter with LEDs - The simple but effective circuit presented here converts an RF input signal into a visible LED indication. Only discrete components are used. The circuit can be used as field strength analyser or RF Wattmeter when a 50 ohms resistor is connected between ground and HF (J1) . Calibration required. Of course you can add extra LED stages in case you want to extend the range. The second picture shows how the circuit can be build on a very small piece of vero-board. __ Designed by Ron Zoetermeer, JO22gb, Netherlands
RGB LED - Lets have some practice and write simple AVR LCD menu routine. For this we need to write LCD control library. I decided not to use one from AVRLIB. LCD controlling isn't difficult just a few lines of code unless you want to make it more universal
RGB LED colour wash light - This PIC based circuit uses Red, Green and Blue high brightness LEDs that are pulse width modulated (PWM) to vary the intensity of each colour LED. This allows effectively any colour to be generated. The circuit is designed to fit into a low voltage Halogen light fitting. A look up table is used to program
RGB LED Showcase Light - RGB LEDs are capable of generating a variety of colours by mixing red, green and blue colours. It is sometimes very interesting to replace single-colour LEDs and produce different colour combinations...__ Electronics Projects for You
Ring-Around LED Flasher This schematic diagram shows a ring-around LED flasher circuit. This circuit will turn off two LEDs and turn on the other two until the timing cycle reverses. This circuit can be configured to flash four LEDs in sequential order by pressing and holding S1 closed until only one of the LEDs is on then releasing it.
Robot Beacon - One of the biggest hurdles to overcome is the "image" of the PIC12C508A chip. We tend to think of it as a single chip, just like any other 8-pin chip. But it's not. It's really equivalent to 5, 6, 8 or even more chips in a single package! And each chip can be programmed to do almost exactly what you want! __ Designed by Collin Mitchell
Robot beacon light display for Mounting on top of a robot - Robot Beacon uses a PIC12C508A OTP (One Time Programmable) 8-pin microcontroller. There is a lot of controversy over the type of microcontroller that should be promoted in a project such as this. There are at least three manufacturers of microcontrollers suitable for this application and it's a nightmare trying to work out the best type to promote. __ Designed by Collin Mitchell
Rotary Encoder Mates with Digital Potentiometer - 6-Mar-03 EDN-Design Ideas Buck IC boosts battery voltage for white LEDIn developing electronic systems, designers look for products or ideas that may benefit from the better performance, smaller size, lower cost, and improved reliability that an IC can offer. Toward that end, the digital potentiometer emerged as an alternative to its mechanical counterpart, the mechanical potentiometer Design by Peter Khairolomour, Analog Devices, San Jose, CA
Running LED - Just for fun I designed and tested two running LED circuits based on CD4017. The first one drives a strip of six LED, while the second one works for a strip of eight LED. Both circuits work in bidirectional running __ Designed by Andrea-Central Italy
Running Message Display - Light emitting diodes are advantageous due to their smaller size, low current consumption and catchy colours they emit. Here is a running message display circuit wherein the letters formed by LED...__ Electronics Projects for You |
