Arduino Powered power supply : Part 2, Arduino + modules (in progress)


The arduino will just be in charge of displaying current/voltage and control.
What do we need ? (I've put the link to the ones i've used, any similar will do) :
  • A screen : A Nokia 5110 style screen is fine
  • A voltage/current  meter : Small module based on INA219 
  • A relay + tact switch  : To disconnect/connect outputs. It starts disconnected.
  • A fan: Using one i had lying around 
  • An arduino micro (any arduino will do, as long as its IOs are 5v)

The first tests showed that all that was drawing a little bit too much current, so a small PCB was added with a 7805 to dispatch power to all the modules and  i2c also for future expansion if needed..

The schematic looks like that (it is work in progress, some parts are missing or incorrect)


The relay module has the protection diode built-in and is wired to be off at reset.

The fan is PWM controlled, it connects directly to the 12V, the PWM is connected to the arduino.


-- To be completed --

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