The pixels use 3 x 5050 RGB LEDs, with a 120 degree beam width. All of the LEDs are
controlled at once so you cannot have one pixel with the three LEDs different colors. (Color
control is per single rectangular 3-LED pixel only) The total max brightness of all LEDs is about
4000mcd. (Please note: mcd ratings of LEDs are notoriously inflated by most LED sellers, so be
extra-skeptical when reviewing LED ratings!)
Sold by the strand, each strand has 21 pixels in series! Each strand has two JST SM 3-pin
connectors so you can connect multiple strands in a row, as many as you wish, just watch for
how much current they want. The two power wires are brought out separately to make wiring
easier, a 2.1mm terminal block adapter is handy here to attach a DC power supply. We have a
12V/5A supply that should be able to drive 3 or more strands (depending on current use). The
LEDs are constant-current driven so you'll have even colors through-out the strand as long as
you have a stable 12V supply
You can drive these with an Arduino using any two microcontroller digital pins, check this library
which also has example code to demonstrate the strands and be sure to read our very
detailed tutorial on usage!. Since these are nearly identical in how they work to t he 36mm
pixels, that guide will get you blinking
75mm Bars - 12V Digital RGB LED Pixels (Strand of 21) (00:00)
TECHNICAL DETAILS
78mm x 18mm (3.1" x 0.7") sticks 9mm deep (0.35")
4mm/0.15" mounting holes 86mm/3.4" apart
75mm / 3" apart on the strand
21 pieces per strand
These pixels use a WS2801 chip for full 24 bit color, constant-current drive
12VDC power, 60mA maximum per pixel (LEDs on full white)
2-pin SPI-like protocol
WS2801 Datasheet for the chip inside each pixel
Brightness per pixel: 4000 mcd combined (we'll try to get a datasheet for the LEDs)