This project is a clock that is using a Bi-Color LED matrix display to show the time. The clock is driven using two 74595 chips for the columns and a pair of ULQ2003 chips for the rows and it is based on PIC 18F4550 . Control of the clock is done via USB, and takes care of lighting up the hour as a red number when it’s time to sleep, and a green one when it’s okay to arise .danielparnell.com writes: [via]
I wanted to make the whole thing fit behind the display, so I was forced to put the processor and the LED driver hardware on their own boards.
Bi-color LED matrix clock - [Link]
This project is and alarm and wake up light based on MSP430 microcontroller by TI. This alarm clock displays time via 7 segment displays and there’s also a feature to adjust the color based on ambient room temperature. Check construction details on the link below. [via]
Msp430 Alarm and wake up light – [Link]
Heart Spark is a heart-shaped pendant which flashes LEDs in time with your heart beat. A polar chest strap with transmitter (sold separately) is used to measure your heart beat, which is transmitted wirelessly to the pendant. An arduino-compatible circuit captures each beat as it happens and flashes LEDs. Schematics and board layout will be available soon. [via]
Heart Spark jewelry beats to your heart - [Link]
The LED Painter is a 16 channel RGB LED controller (or 48 independent LEDs) using the Texas Instrument TLC5940. This PCB is improved with a better layout that allows easy connection of independent LEDs (not just RGB), as well as the ability to daisy chain multiple boards together. Each TLC5940 has 16 channels with 12 bit grayscale PWM control on each channel. Your microcontroller will connect to the TLC5940 using only a couple of pins and a serial like interface for controlling the intensity of each channel.
LED Painter – [Link]
This project is a small and portable LED Color Organ powered from batteries. The LEDs and components needed are attached to the front of the battery case. The signal is split up into three different channels, and each of the channel has it’s own filter circuit for easy adjustment. Afterward, the signal is send out to an LED bargraph ladder circuit. There are three different colors can be displayed here: red/yellow, green/white, and blue/green. [via]
Here is a new version of the classic color organ, where different color lights are triggered by different frequencies of sound, resulting in a display that flashes along to music. In this case the newer type high intensity LEDs (3000 – 5000mcd) were used along with a very simple discrete transistor drive circuit. The design goals included small size and excellent portability, as well as long battery life.
Discrete LED Color Organ – [Link]
This project will show you how to make a holiday star using LEDs, a battery, some resistors, a ATTiny 45 and a MOSFET transistor. You can use them as table decorations, for your desk or around the house.
LED holiday star – [Link]
This is a control circuit that lights a LED array and then dims off using a transistor and 4 more simple components (resistors-capacitors). It is an extremely practical circuit. It can be used as a car dome off-delay light, or in your tent when you go camping, or even as a security light. It can be powered with any voltage from 4 to 15 volts, and it can control up to 78 high brightness LEDs @ 12V power supply (or 104 LEDs @ 15V).
LED Off Delay with dimming effect - [Link]
This project is a LED array PWM dimmer using 555 timer IC. The 555 timer IC is configured as a PWM generator. A potentiometer controls the charge and discharge times and thus the duty cycle of the PWM. As PWM duty cycle is varying the brightness of the led changes. Check schematic on the link below.
An LED Array PWM Dimmer with the 555 - [Link]
Tron Legacy Disc was gutted and the paltry 6 LEDs were removed and replaced with 30 individually addressable, high output blue LEDs. It is now also rechargeable with its modified base. For now, the Netduino is temporarily mounted in the center but will be replaced with a Netduino Mini. Also, there is an accelerometer mounted in the device, but has yet to be activated in the software. [via]
Complete Tron Legacy Disc Toy Rebuild – [Link]
This application note discuss a Boost driver for long LED strings. [via]
The long strings of LEDs commonly found in TV and display backlighting, street lights, and parking garage lights require a current driver capable of producing high voltages. This reference design provides such a driver using the MAX16834, and demonstrates how very-high dimming ratios can be obtained.
Boost driver for long LED strings – [Link]