Circuit Documentation

Summary of the Circuit

This circuit is designed to control a 12V PWM fan using an Arduino Nano microcontroller. The fan's speed can be adjusted via a potentiometer, and the system is powered by a 5V battery connected to the Arduino and a 12V battery connected to the fan. A rocker switch (SPST) is used to control the power to the fan. The Arduino reads the potentiometer's output to adjust the fan's PWM signal accordingly.

Component List

Arduino Nano

• Microcontroller board based on the ATmega328P
• It has a variety of digital and analog I/O pins
• Can be powered via the USB connection or with an external power supply

12V PWM Fan (120mm)

• A 120mm fan with a 12V power requirement
• Supports PWM for speed control
• Includes a tachometer output for RPM feedback

Rocker Switch (SPST)

• A single-pole single-throw (SPST) switch
• Used to connect or disconnect the circuit

Potentiometer

• A variable resistor with three terminals
• Provides an adjustable voltage output

12V Battery (Small Size)

• A power source for the 12V fan
• Provides the necessary voltage for the fan operation

5V Battery

• A power source for the Arduino Nano
• Ensures the microcontroller has a stable 5V supply

Wiring Details

Arduino Nano

• D11/MOSI: Connected to the PWM pin of the 12V PWM Fan for speed control
• VIN: Connected to the + terminal of the 5V Battery
• GND: Common ground with the 5V Battery, 12V PWM Fan, 12V Battery, and Potentiometer
• 5V: Connected to the VCC pin of the Potentiometer
• A0: Connected to the Output pin of the Potentiometer for reading the voltage level

12V PWM Fan (120mm)

• PWM: Controlled by the D11/MOSI pin of the Arduino Nano
• +12V: Connected to the 2 pin of the Rocker Switch (SPST)
• GND: Common ground with the Arduino Nano, 5V Battery, 12V Battery, and Potentiometer

Rocker Switch (SPST)

• 1: Connected to the VCC pin of the 12V Battery
• 2: Connected to the +12V pin of the 12V PWM Fan

Potentiometer

• GND: Common ground with the Arduino Nano, 5V Battery, 12V PWM Fan, and 12V Battery
• Output: Connected to the A0 pin of the Arduino Nano
• VCC: Connected to the 5V pin of the Arduino Nano

12V Battery (Small Size)

• VCC: Connected to the 1 pin of the Rocker Switch (SPST)
• GND: Common ground with the Arduino Nano, 5V Battery, 12V PWM Fan, and Potentiometer

5V Battery

• +: Connected to the VIN pin of the Arduino Nano
• -: Common ground with the Arduino Nano, 12V PWM Fan, 12V Battery, and Potentiometer

Documented Code

sketch.ino

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

}

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

}

documentation.txt

(No additional documentation provided for the code)