Circuit Documentation

Summary

This circuit is designed to control a humidifier, a fan, and a buzzer, with the capability to indicate status through red and green LEDs. The system is powered by a 12V battery, with a step-down buck converter to provide the necessary 5V supply. An Arduino Mega 2560 serves as the central microcontroller unit, interfacing with a KY-019 relay module to control the power flow to the humidifier. The circuit's design allows for expansion and integration with additional sensors or actuators if needed.

Component List

Arduino Mega 2560

• Microcontroller board based on the ATmega2560
• Provides a large number of IO pins for interfacing with various components

Humidifier

• A device that increases humidity (moisture) in a single room or an entire building

Buzzer

• An audio signaling device, which may be mechanical, electromechanical, or piezoelectric

Fan

• An electric device that blows air

LED: Two Pin (red)

• A red light-emitting diode that can be used as an indicator

LED: Two Pin (green)

• A green light-emitting diode that can be used as an indicator

KY-019 Relay module 1 channel

• A relay module that can be used to control high power/high voltage devices

Step down Buck converter

• A DC-DC power converter that steps down voltage from its input to its output

12V Battery

• A battery providing a 12V supply to power the circuit

Wiring Details

Arduino Mega 2560

• 5V: Connected to the 5V supply net
• GND: Connected to the ground net
• D53: Connected to the anode of the red LED
• D51: Connected to the anode of the green LED
• D49: Connected to the signal pin of the KY-019 relay module

Humidifier

• 5V: Connected to the 5V supply net
• GND: Connected to the ground net

Buzzer

• POSITIVE: Connected to the 5V supply net
• NEGATIVE: Connected to the ground net

Fan

• 5V: Connected to the 5V supply net
• GND: Connected to the ground net

LED: Two Pin (red)

• Anode: Connected to pin D53 on the Arduino Mega 2560
• Cathode: Connected to the ground net

LED: Two Pin (green)

• Anode: Connected to pin D51 on the Arduino Mega 2560
• Cathode: Connected to the ground net

KY-019 Relay module 1 channel

• 5V: Connected to the 5V supply net
• GND: Connected to the ground net
• S: Connected to pin D49 on the Arduino Mega 2560

Step down Buck converter

• IN +: Connected to the VCC of the 12V battery
• IN - GND: Connected to the GND of the 12V battery
• OUT +: Connected to the 5V supply net
• OUT - GND: Connected to the ground net

12V Battery

• VCC: Connected to the IN + of the step-down buck converter
• GND: Connected to the IN - GND of the step-down buck converter

Documented Code

Arduino Mega 2560 - sketch.ino

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

}

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

}

Arduino Mega 2560 - documentation.txt

(No additional documentation provided for the code)