Circuit Documentation

Summary

This circuit is designed around an Arduino Nano microcontroller and includes a variety of components that interact with the microcontroller to perform specific functions. The circuit features a PWM Fan controlled by the Arduino, a trimmer potentiometer for adjustable input, a buck converter to step down voltage, an I2C OLED display for user interface, and resistors for current limiting and signal conditioning. The Arduino Nano is powered through a buck converter connected to a 12V power supply, ensuring a stable 5V supply to the microcontroller and other components.

Component List

Arduino Nano

• Microcontroller board based on the ATmega328P
• It has a variety of digital and analog I/O pins.

Trimmer Potentiometer

• Adjustable resistor with a 10k Ohm value
• Used for providing an adjustable voltage input.

Resistor (1k Ohm)

• Fixed resistor with a 1k Ohm value
• Used for current limiting and signal conditioning.

PWM Fan

• A fan with a Pulse Width Modulation (PWM) control input
• Allows for speed control via the PWM signal from the Arduino Nano.

Buck Converter

• A DC-DC converter that steps down voltage from a higher level to a lower level
• Provides a stable power supply to the Arduino Nano and other components.

12V Power Supply

• Provides the input voltage to the buck converter
• Powers the PWM Fan directly.

I2C OLED 128x64

• An OLED display with I2C communication interface
• Used for displaying data and information to the user.

Wiring Details

Arduino Nano

• D2 connected to one end of a 1k Ohm resistor
• D9 connected to the PWM input of the PWM Fan
• VIN connected to the OUT+ of the Buck Converter
• GND connected to the common ground net
• 5V connected to the VCC of the I2C OLED and one end of the trimmer potentiometer
• A5 connected to the SCK of the I2C OLED
• A4 connected to the SDA of the I2C OLED
• A2 connected to the wiper of the trimmer potentiometer

Trimmer Potentiometer

• leg1 connected to the GND net
• leg2 connected to the 5V net
• wiper connected to A2 on the Arduino Nano and one end of a 1k Ohm resistor

Resistor (1k Ohm)

• One end connected to D2 on the Arduino Nano
• The other end connected to the wiper of the trimmer potentiometer

PWM Fan

• GND connected to the common ground net
• 12V connected to the + of the 12V power supply
• FG connected to the other end of a 1k Ohm resistor
• PWM connected to D9 on the Arduino Nano

Buck Converter

• IN+ connected to the + of the 12V power supply
• IN- connected to the common ground net
• OUT+ connected to VIN on the Arduino Nano
• OUT- connected to the common ground net

12V Power Supply

• + connected to the 12V of the PWM Fan and IN+ of the Buck Converter
• - connected to the common ground net

I2C OLED 128x64

• GND connected to the common ground net
• VCC connected to the 5V net
• SCK connected to A5 on the Arduino Nano
• SDA connected to A4 on the Arduino Nano

Documented Code

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

The provided code is a template for the Arduino Nano with empty setup() and loop() functions. The setup() function is intended for initialization code that runs once when the microcontroller is powered on or reset. The loop() function contains the main code that will run repeatedly, allowing the microcontroller to perform its tasks continuously. Additional code should be added to control the PWM Fan, read the trimmer potentiometer, and update the I2C OLED display based on the circuit's requirements.