Brilldea

PolkaDOT-51

The PolkaDOT-51 is an RGB LED pixel capable of 10-bit resolution and 150mA of current per each of the three constant current channels. The PolkaDOT-51 is the first in a series of products that utilize the Allegro MicroSystems A6281 three channel, constant current LED controller.

The PolkaDOT-51 makes for an easily controllable and daisy chainable LED pixel product for all your hobby, art, ambient mood lighting and other LED projects. In addition to the PolkaDOT-51 we offer two carrier boards that make "wiring up" a chain of PolkaDOT-51s much easier. One carrier board is a linear strip which accommodates up to 5 PolkaDOTs. The other carrier board has four PolkaDOTs arranged in a 2x2 matrix. Any unused position can be solder bridged to pass the signals through.

The PolkaDOT-51 operates on 5V to 6V DC from the factory, but you can remove the SMT RGB LED and add your own LEDs with the four pin header and operate at higher voltages. For instance you can remove the SMT LED and add our RGB LED ribbon and run the system at 12V DC.

The A6281 IC acts like a serial shift register meaning that up to 250 pixels can be connected in a chain and controlled with only four output lines of a micro. The IC also has a built in settable clock so that your microcontroller can clock out the data and then go do something else instead of constantly clocking the IC (for brightness variation). Beyond the 10-bit resolution there is a 7-bit dot correction for fine adjustment and color matching of LEDs.

The PolkaDOT-51 is a two layer PCB that is the size of a USA quarter coin. There are six signals on each side of the PCB, one side is the incoming and the other side is the outgoing. The six signals include power, ground, serial clock, serial data, latch and output enable. Brilldea provides a driver written for the Parallax Propeller Microcontroller and furthermore the PolkaDOT-51 is easily controlled by any PIC, AVR, Arduino or Basic Stamp module.

The PolkaDOT-51 is sold without headers, but easily accepts 0.1" 6 pin headers of either vertical or right angle orientation. In addition the edges of the PCB are plated to assist in surface mounting the PolkaDOT-51 on a carrier board eliminating cables when the pixels are spaced close together. When using the PolkaDOT-51 Rev 0 in a surface mount application note that a small solder bridge is required from the edge of the PolkaDOT to the signal pad on the top or bottom of the PolkaDOT PCB (see the data sheet).

Check out our video of the PolkaDOT-51 in action!