The unsolved: when I connect power and signal lines to my Arduino - while power is on - I potentially kill it. I have fried 2 so far.
- I have build an DMX-controlled lighting fixture, which consists of the fixture and a Controller Box.
- The fixture houses 2 Arduino's (5V), 2 steppers, 2 drives (36V), 2 fans (24V) and some temperature sensors.
- The controller box houses 1 Arduino, amongst other electronics.
The controller box receives DMX and does calculations an send controls via I2C to the fixture.
There is a 8 pole connector between fixture and controller box.
1 - GND 2 - 5v 3 - 24v 4 - 36v 5 - CLK (i2c) 6 - SDA (i2c) 7 - signal line (used as charge pump) 8 - reset
All wires are shielded(but the shield is only connected AFTER the initial pins make contact)
When the power on the controller box is ON and i connect the light Fixture with the 8-pole connector my arduino goes to heaven.
My own idea's so far:
- Voltage spike, because the connection wires is grounded after it connects the pins.
- Some strange flyback? via the Arduinos in the light fixture? I connected everything straight to the 5v pins, not using the regulator.
- no idea
Any help on a way to search for the most likely cause of the problem would be greatly appreciated.