I am trying to apply a PWM signal to a high power LED.
For that, I am following this tutorial on building a CC source that can be interfaced with a microcontroller: https://www.instructables.com/id/Circui ... ower-LED-s
The following diagram from the website shows the circuit that I am going to use:
In the description it says:
Maybe I am too stupid to understand this ... does this mean that there should be a software setting called "open collector" that I have to use when I initialize the GPIO pin in python (like initializing an input pin and setting the initial value to high or low)?if your micro-controller is 3.3V or less, you need to use circuit #4, and set your micro-controller's output pin to be "open collector" - which allows the micro to pull down the pin, but lets the R1 resistor pull it up to 5V which is needed to fully turn on Q2.
The search gave me lots of hits for "open collector", but I couldn't find any that was dealing with a software setting ...
How do I set my GPIO pin to "open collector" mode?? Or does it mean something completely different?