Circuit Documentation

Summary

This circuit integrates a variety of components including microcontrollers, sensors, a motor, a relay, and a display. The primary microcontroller is an ESP32-S3, which interfaces with a DHT22 temperature and humidity sensor, an Adafruit INA260 current and voltage sensor, an HC-SR04 ultrasonic sensor, an SGP41 VOC and NOx sensor, and a 0.96" OLED display. The circuit also includes an Arduino UNO, which is connected to a rotary encoder. A DC Mini Metal Gear Motor and a 12V relay are controlled by the ESP32-S3. Power management is handled by a step-down buck converter, which steps down the voltage from a 12V battery. The circuit also includes an SD card module for data logging.

Component List

Microcontrollers

• ESP32-S3: A powerful microcontroller with Wi-Fi and Bluetooth capabilities.
• Arduino UNO: A widely-used microcontroller board based on the ATmega328P.

Sensors

• DHT22: A sensor for measuring temperature and humidity.
• Adafruit INA260: A high-precision current and voltage sensor.
• HC-SR04 Ultrasonic Sensor: A sensor for measuring distance via ultrasonic waves.
• SGP41 VOC and NOx Sensor: A sensor for detecting volatile organic compounds and nitrogen oxides.

Actuators

• DC Mini Metal Gear Motor: A small motor for mechanical movements.
• 12V Relay: An electromechanical switch used for controlling high power devices.

Power Components

• 12V Battery (mini): A power source for the circuit.
• Step down Buck Converter: A device that steps down voltage from a higher level to a lower level.

Display

• 0.96" OLED: A small display for showing information.

Storage

• SD SDHC: An SD card module for data logging.

Miscellaneous

• Resistors: Various resistors used for current limiting and voltage division.
• LED (red): A light-emitting diode for indication purposes.

Wiring Details

ESP32-S3

• 3v3 connected to SD card module 3V3.
• GND connected to common ground.
• GPIO16 connected to DHT22 Out.
• GPIO18 connected to SCL line shared with Adafruit INA260 and SGP41 sensor.
• GPIO9 connected to Arduino UNO D1.
• GPIO10 connected to 12V relay IN.
• GPIO11 connected to 0.96" OLED SCK.
• GPIO40 connected to SD card module CS.
• GPIO39 connected to SD card module MOSI.
• GPIO37 connected to HC-SR04 TRIG.
• GPIO36 connected to HC-SR04 ECHO.
• GPIO35 connected to SD card module CLK.
• GPIO0 connected to SD card module MISO.
• GPIO21 connected to 0.96" OLED SDA.
• GPIO19 connected to SDA line shared with Adafruit INA260 and SGP41 sensor.

Arduino UNO

• GND connected to common ground.
• Vin connected to step-down converter OUT +.
• D2 connected to rotary encoder A.
• D3 connected to rotary encoder B.

DHT22

• + connected to common VCC.
• Out connected to ESP32-S3 GPIO16.
• - connected to common ground.

Adafruit INA260

• VCC connected to common VCC.
• GND connected to common ground.
• SCL connected to ESP32-S3 GPIO18.
• SDA connected to ESP32-S3 GPIO19.
• IN- connected to one side of a resistor network.
• IN+ connected to DC Mini Metal Gear Motor IN2.

DC Mini Metal Gear Motor

• IN1 connected to common ground.
• IN2 connected to Adafruit INA260 IN+.

12V Relay

• NO connected to LED anode.
• COM connected to 12V battery +.
• NC not used in this circuit.
• IN connected to ESP32-S3 GPIO10.
• DC- connected to common ground.
• DC+ connected to common VCC.

Resistor Network

• Several resistors are connected in various configurations for current limiting and voltage division.

LED (red)

• anode connected to 12V relay NO.
• cathode connected to 12V battery -.

12V Battery (mini)

• + connected to step-down converter IN + and 12V relay COM.
• - connected to LED cathode and step-down converter IN - GND.

Step down Buck Converter

• IN + connected to 12V battery +.
• IN - GND connected to 12V battery -.
• OUT + connected to common VCC.
• OUT - GND connected to common ground.

0.96" OLED

• GND connected to common ground.
• VDD connected to common VCC.
• SCK connected to ESP32-S3 GPIO11.
• SDA connected to ESP32-S3 GPIO21.

HC-SR04 Ultrasonic Sensor

• VCC connected to common VCC.
• TRIG connected to ESP32-S3 GPIO37.
• ECHO connected to ESP32-S3 GPIO36.
• GND connected to common ground.

SGP41 VOC and NOx Sensor

• VIN connected to common VCC.
• GND connected to common ground.
• SCL connected to ESP32-S3 GPIO18.
• SDA connected to ESP32-S3 GPIO19.

SD SDHC

• 3V3 connected to ESP32-S3 3v3.
• CS connected to ESP32-S3 GPIO40.
• MOSI connected to ESP32-S3 GPIO39.
• CLK connected to ESP32-S3 GPIO35.
• MISO connected to ESP32-S3 GPIO0.
• GND connected to common ground.

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:

}

Note: The provided code for the Arduino UNO is a template and does not contain any functional code specific to this circuit.