Hello,
I am having hard times with a MT3608 step up boost converter.
I set the boost converter to output 12V from an input of 3.7 from a Li-ion battery.
This is the basic setup, arduino PWM output l, battery and load are connected to a 2N2222A.
I would like to control the voltage with PWM but even if I set it the Analog write to 0 I am still getting 10 volts coming out.
Do you know how can I control better the output voltage?
I also thought to make a custom pcb with a digital potentiometer but the ones I have seen can't handle more than 2 mA.
Yes I know, in fact the PMW should control a transistor. From what I understood if for example I give like 50% duty on an output of 12, I should get 6 volts. But for some reason it is not happening.
All it is doing even in your last schematic is shorting the output of the 3608.
Also you have no base current limit resistor in the base circuit of Q1.
Your circuit will not control the 3608.
How do you expect current to flow through the motor?
Can you please tell us your electronics, programming, arduino, hardware experience?
Have you got the 3608 and built the circuit, or have you the PCB module.
Regarding my experience is very basic, I am following tutorials online.
The 3608 I am using is a module but it is all wired and working properly.
I just need to control the output voltage that is coming out from the 3608 and going straight to the motor.
My main problem is that I cannot control digitally the voltage output of the MT3608 module. It is possible I do it digitally with the signal I send to the transistor through the channel 9?
First you need to put a 470 ohm resistor in the base connection of the transistor as shown in schematic below. Also,make sure that all the GNDs are connected to the UNO GND, this is important.
Then you need to write code using the analogWrite() function to output PWM to pin 9