I am design a circuit to control fan speed using a 3.3V MCU and seems the MAX6615 can do everything.
The MAX6615 Vcc is connected to the 3.3V
The fan I plan to use is AFC0612DB-F00, https://www.delta-fan.com/Download/Spec/AFC0612DB-F00.pdf .
I can connect it to typical 4 pin connector: 1:GND, 2:12V, 3:Sense, 4:Control
Following the Typical application circuits in datasheet and , I am making the schematic as below:
My main question is
1. Which one of the 3 PWM output way should I use? I want to use the 3rd way, which is the figure 6, but not sure.
2. What is the voltage should I use for the VFG on the fan? which is used for the tach and PWM? on the drawing above, I am using 12V the FVCC. But I want to know if I can directly use 3.3V? That will eliminate several parts.
