Diagrams Schematics and PCB Parts List Programming Code Other Flex Circuits Building the Flex LED Ribbon New Flex LED Ribbon LED Shirt Spec's 2000 Red LED's ATMEGA168 microcontroller is used to control the LED matrix 8 PNP transistors are used to control the rows CAT4016 LED controller is used to control the LED columns The shifters have a constant current control so that resistors don't have to be used! Power supply is two 5 volt regulators. The LED supply is a 5 volt 5 amp regulator. This is because the LEDs are in a parallel circuit and each LED uses 20mA so 20mA * 250 LEDs equals 5Amps per row! But thankfully only one row is on at a time. The rows are scanned faster than your eye can see so it looks like all 8 rows are on at the same time. | The project is to make a flexible LED ribbon sign. The sign will be able to wrap around objects or around corners. I am making the sign 5 feet long and 2" wide. It will have a total of 2000 LEDs that will make up a 8 X 250 LED matrix! Building has started and the finished Flex LED sign is not yet done. I hope to have it finished to show off at the MAKE FAIRE in Austin, TX this year. I am going to wrap the ribbon sign around a T-shirt and wear it to the Make Faire.   The LED Flex Sign is a work in progress so come back to see the construction updates! UPDATES: 9-30-2008 Copper etching has failed!!! Redesign using copper tape and overhead transparencies |
