April 2017 1
We wanted to create light effect: short fades of 10W Leds which can be put on stage and are triggered via MIDI.
- 8 Channels
- Up to 10W LEDs at 12V per channel
- One LED Driver CAT 4101 per channel
- PWM Dimming of the brightness via Midi
- MIDI-IN and through
We used a dedicated LED Driver for each channel. Its the CAT 4101 which can drive up to 1A. A TLC5940 creates the PWM Signal. Up to 16 PWM Channels from the TLC (here we use only 8) are controlled via SPI from an ATMEGA168. Like this the load of the ATMEGA is kept low when a lot of dimming is performed. Midi-In is straight forward through an Optocoppler.
The MIDI Channel can be set with an hex coded 16 stage switch.
Our sketch contains a programm for fast dimming of the LEDs. Like this an LED will flash and slowly decay, which is a cool effect together with sound. You can see an example here (with 3W LEDs):
You can of course write your own sketch using ours. A good start is the example in the TLC5940 Arduino Library.