Hi everyone. Nice to find somewhere hopefully that can help me.
Now I am a bit of a hacker. I have an idea how something works and then when it doesn't I sort it out. well this latest one has been sorting out for about a month and half now.
I've already built a FDM 3d printer and decided an SLA would be fun so using a RPI3 I plugged it all in.
It all works. except I cant get the lights to turn on when the Pi says so.
as in the schematic, I have the pi connecting on GPIO 22. The first thing it goes to is a adafruit level shifter, due to the mosfet needing 5v to fully open. this then opens the power to the buck down shifter and hey presto on come the 3w leds.
only it doesn't. as the image shows 3.3v one side, 5v on the other side and going to the mosfet however when I connect the wires up it then shows 2.5v and the leds doesn't power up fully. I take it the mosfet is proportional to the V it receives but the should be 5v.
If I just connect the 5v wire from the Pi then full brightness.
sorry for going on but I thought a full run down of the issue was best. hope someone knows what is going on and how I can fix it.
Mike
Now I am a bit of a hacker. I have an idea how something works and then when it doesn't I sort it out. well this latest one has been sorting out for about a month and half now.
I've already built a FDM 3d printer and decided an SLA would be fun so using a RPI3 I plugged it all in.
It all works. except I cant get the lights to turn on when the Pi says so.
as in the schematic, I have the pi connecting on GPIO 22. The first thing it goes to is a adafruit level shifter, due to the mosfet needing 5v to fully open. this then opens the power to the buck down shifter and hey presto on come the 3w leds.
only it doesn't. as the image shows 3.3v one side, 5v on the other side and going to the mosfet however when I connect the wires up it then shows 2.5v and the leds doesn't power up fully. I take it the mosfet is proportional to the V it receives but the should be 5v.
If I just connect the 5v wire from the Pi then full brightness.
sorry for going on but I thought a full run down of the issue was best. hope someone knows what is going on and how I can fix it.
Mike
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