Citizen Electronics Co., Ltd. recently reported having developed the LMC10B series of LED lighting modules with built-in AC drive circuits using innovative circuit technology.
LEDs are usually driven by DC (direct current) power supply. Where an AC (alternating current) power supply is used, a DC converter circuit is needed. Issues to be resolved with DC power driven LEDs include the complexity of the circuit increasing the number of components, and electrical noise generated. [via]
AC powered 22 watts 1000 lumen LED module – [Link]
Last year in one of my classes we were required to make an ‘artefact’ or something that reflects the interests of the class. Most people make posters and the past two quarters that’s what my class did too. Posters however are static, usually boring, and don’t reflect that fact that everyone in the class is an EE major. We decided posters are for noobs and decided to go off the wall a little and make an LED matrix display. Lucky one of my friends John Wathen already had this beautiful 16×24 Green SMD LED matrix that he built back in high school.
16×24 LED Matrix – [Link]
Arduino based POV globe capable of displaying monocolour bitmaps upto 72 pixels high and x width. (uses 72 LEDs, and one input to get rotation speed)
Arduino byte array for images are generated using the c# program included in this project
Image displayed is synch’d to speed of motor using a reed switch, this allows image to display around hole globe correctly, and maintain a constant position.
Code has been added to move the image slowly (so globe rotates nicely)
POV Globe using arduino (atmega328P) and 72 SMD Leds – [Link]
Steve Lodefink shows us this awesome World Control Panel he built with his son. [via]
My son Harlan and his friend love to play “agents” and he asked me if we coud build “a panel that has a bunch of switches that turn on some random lights”. We worked on it for about 3 weeks, and this is what we came up with. The panel boasts the following features:
World Control Panel – [Link]
sponges writes: [via]
Though there are many Instructables on some aspect of how to make circuit boards, this one is different. This is also an instructable on how to make the things you need to make circuit boards, specifically, a flamboyant business card toy. Over the past six months I have set up fairly complete printed circuit board fabrication lab in my apartment, cheaply and safely, and I intend to cover all aspects of the process, from start to finish, in as wide a scope as I can. Some of it you may have seen before, but here it is all in one place, in detail, with references.
How-To: Set Up a Basement PCB Fab & Use It To Make a POV Business Card – [Link]
Lampduino is a computer-controlled free-standing floor lamp, comprised of an 8×8 RGB LED matrix. The lamp stands 45″ high and 18″ wide. Light emanates from both sides. It has various display modes, as well as an included editor for creating animations. The lamp is controlled via an application running on a PC host. The display modes include realtime drawing, playback of previously created animations, snow, meteor, plasma, and synchronization with music. With its endless available colors, Lampduino can also be used for color therapy, or as a mood light. When running standalone, without a computer, it plays a soothing plasma simulation.
Lampduino – an 8×8 RGB Matrix Floor Lamp – [Link]
rsdio writes: [via]
Why regulate the voltage from your supply when you really need a controlled current to drive an LED? Any regulator is less than 100% efficient, and the losses increase as more current is drawn. It looks like the circuit in this application note would allow you to skip the voltage regulator and thus avoid massive losses. You would still use a regulator for the µC part of the circuit where a steady voltage is needed, but the LEDs could be driven independently. Unfortunately, the circuit as shown has way too many parts, but I have a feeling that the basic idea can be used in a much smaller circuit after careful study. In the last several years, I’ve designed USB-powered boards with almost 200 LEDs, and I wish I had known about this technique to squeeze every last ounce of energy out of the limited 2.5 W USB supply.
This LED driver reference design drives a 700mA constant current to a single string of LEDs with forward voltages up to 60V. The design allows PWM dimming based on supply chopping. The input power supply is chopped on and off at 300Hz to 1kHz frequency to achieve LED brightness control. The driver uses a fixed-frequency boost converter, controlled by the MAX16834 LED driver. This unique reference design limits the input inrush current to negligible levels without compromising either the input or output filtering. Design schematics and test results are provided.
App note: MAX16834 high-power LED driver – [Link]