I have 6 1 watt leds all connected to their own mosfet, I can upload a sketch through USB and cannot view the sketch until I plug back into 12v..is that normal , I know the USB is only 5.5 v
only one led flashes at a time during the sketch
Thanks for any help
How are the LEDs and MOSFETs connected? What is providing the current limiting for the LEDs?
The USB can supply 5V at 500mA. A 1W LED will draw roughly 300 to 500 mA (if the forward voltage drop is 3V to 2V). It may be that a single 1W LED will draw too much current to be run off USB power.
johnwasser:
How are the LEDs and MOSFETs connected? What is providing the current limiting for the LEDs?The USB can supply 5V at 500mA. A 1W LED will draw roughly 300 to 500 mA (if the forward voltage drop is 3V to 2V). It may be that a single 1W LED will draw too much current to be run off USB power.
That is probably the case then, leds are wired to mosfets and a 33 ohm resistor on each channel ,
Everything works fine when run through 12v just nothing when USB
I just thought I had it working at one point and now nothing I could be wrong tho
So do you know if you can power the arduino with USB and 12v supply at same time to upload code and see sketch or will I have to plug and unplug until I'm finished writing the code I want?
CruzReagan:
So, do you know if you can power the arduino with USB and 12v supply at same time to upload code and see sketch or will I have to plug and unplug until I'm finished writing the code I want?
You can leave the 12V connected at the same time as the USB.