Breakoutboard mit dem TLC5940 16-Kanal 12-Bit LED PWM Controller. Mit diesem IC lassen sich bis zu 16 LED Kanäle steuern, dabei lässt sich ein maximaler Strom über einen externen Widerstand einstellen. Damit man Unterschiede von einzelnen LEDs (z.B. in einer Matrix) ausgleicht lässt sich jeder Kanal nochmal Feinjustieren (6-Bit Auflösung), dieser Wert kann im internen EEProm ablegen.


The TLC5940 is a 16 channel PWM unit with 12 bit duty cycle control (0-4095), 6 bit current limit control (0-63), and a daisy chainable serial interface. This breakout board is a good way to take full advantage of this useful IC. All 16 PWM channels are broken out to standard 0.1" headers, which run alongside convenient voltage and ground rails. Also, because the TLC5940 can be daisy-chained, the breakout is designed to support that feature. On the left-hand side of the board all serial inputs are broken out to 0.1" headers and likewise with output on the right-hand side.
Use this board to increase the number of PWM pins available to your microcontroller for applications such as Monocolor, Multicolor or Full-Color LED Displays, LED Signboards, Display Backlighting, Servo control, or any other project where a large number of PWM drivers are necessary.

Note: While each 3-pin PWM header is 0.1" spaced, the space between each header is slightly larger in order to accommodate servo connections. In order to make this board suitable for use with servos, 2.2k pull-up resistors have been included on each output as well. Finally, the 2.2k resistor on the Iref pin sets the output current to 17.8mA but a parallel through-hole connection is provided for an additional resistor to increase the current if necessary. To determine the resistor value you need for a given output check the equations provided on the schematic.

http://bildr.org/2012/03/servos-tlc5940-arduino/