Circuit Documentation

Summary

This circuit integrates various components controlled by an Arduino UNO microcontroller. It includes DC motors, a relay module, a fan, a DHT11 temperature and humidity sensor, an I2C LCD 16x2 screen, a 9V battery, and a 2x 18650 battery pack. The Arduino UNO manages the relay modules which in turn control the power to the DC motors and the fan. The DHT11 sensor provides environmental data displayed on the I2C LCD screen. The circuit is powered by both a 9V battery and a 2x 18650 battery pack.

Component List

• Arduino UNO: A microcontroller board based on the ATmega328P, with a variety of digital and analog I/O pins.
• DC Motor: An electric motor that runs on direct current (DC) electricity.
• Relay Module 1 Channel: An electrically operated switch that allows you to control a high power circuit with a low power signal.
• Fan: An electronic device used to create a flow of air.
• 9V Battery: A standard size of battery typically used in small electronic devices.
• DHT11: A basic, ultra low-cost digital temperature and humidity sensor.
• I2C LCD 16x2 Screen: A liquid crystal display capable of displaying 16 characters per line in 2 lines, with an I2C interface.
• 2x 18650 Battery Pack: A battery pack consisting of two 18650 lithium-ion cells.

Wiring Details

Arduino UNO

• 3.3V connected to DHT11 VCC
• 5V connected to Relay modules 5V, I2C LCD VCC (5V)
• GND connected to Relay modules GND, I2C LCD GND, DHT11 GND
• A4 (SDA) connected to I2C LCD SDA
• A5 (SCL) connected to I2C LCD SCL
• D2 connected to DHT11 DATA
• D3 connected to Relay module 1 channel S (6fa9f017)
• D6 connected to Relay module 1 channel S (6cdf870d)

DC Motors

• Pin 1 of all DC Motors connected to 2x 18650 battery pack GND
• Pin 2 of all DC Motors connected to Relay module 1 channel NO (6cdf870d)

Relay Module 1 Channel (6fa9f017)

• 5V connected to Arduino UNO 5V
• GND connected to Arduino UNO GND
• S connected to Arduino UNO D3
• COM connected to 9V Battery -
• NO connected to Fan GND

Relay Module 1 Channel (6cdf870d)

• 5V connected to Arduino UNO 5V
• GND connected to Arduino UNO GND
• S connected to Arduino UNO D6
• COM connected to 2x 18650 battery pack VCC
• NO connected to DC Motors pin 2

Fan

• GND connected to Relay module 1 channel NO (6fa9f017)
• 5V connected to 9V Battery +

DHT11

• VCC connected to Arduino UNO 3.3V
• GND connected to Arduino UNO GND
• DATA connected to Arduino UNO D2

I2C LCD 16x2 Screen

• VCC (5V) connected to Arduino UNO 5V
• GND connected to Arduino UNO GND
• SDA connected to Arduino UNO A4 (SDA)
• SCL connected to Arduino UNO A5 (SCL)

9V Battery

• - connected to Relay module 1 channel COM (6fa9f017)
• + connected to Fan 5V

2x 18650 Battery Pack

• GND connected to DC Motors pin 1
• VCC connected to Relay module 1 channel COM (6cdf870d)

Documented Code

Arduino UNO Code (sketch.ino)

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 with empty setup() and loop() functions, which are the standard structure for Arduino sketches. The setup() function is intended for initialization code that runs once at startup, and the loop() function contains code that runs continuously as long as the Arduino is powered. Additional code would be required to control the relay modules, read data from the DHT11 sensor, and display information on the I2C LCD screen.