I'm designing a fan that is supplied through a step-up flyback converter (5V > 12V LM2585 from TI).
A USB cable is connected to one USB3 port from my laptop and to an Arduino Nano ; The Arduino Nano gives 5V to the input of the converter ; The output of the converter gives 12V to the fan. The fan needs 12V this is why I'm using the converter.
The converter's datasheet gives circuits example. I built this one below. Vin is connected to the 5V from the Nano.
I get 12V@0.6A at the output. The problem is my fan only needs 0.3A. I don't want to burn it with to much current so the question is simple, how can I do ?
I thought of a current divider with on one branch one resistor whose power rating is something around 5W (12V * 0.3A = 3.6W), and on the other branch the fan getting the remaining 0.3A, the nodes connecting the two branches being the 12V from the converter and GND.
Can I go for it ?