Circuit Documentation

Summary

This circuit involves an ESP32 microcontroller interfacing with various components including a DC motor, temperature sensor (LM35), NPN transistor, LEDs, resistors, a piezo buzzer, a servo motor, and an MQ 135 gas sensor. The circuit is designed to control and monitor these components, with the ESP32 serving as the central control unit.

Component List

DC Motor

• Description: A motor that converts electrical energy into mechanical energy.
• Pins: pin 1, pin 2

Temperature Sensor (LM35)

• Description: A sensor that provides an analog output proportional to the temperature.
• Pins: +Vs, Vout, GND

NPN Transistor (CBE)

• Description: A transistor used for switching and amplification.
• Pins: collector, base, emitter

LED: Two Pin (red)

• Description: A red light-emitting diode.
• Pins: cathode, anode

LED: Two Pin (green)

• Description: A green light-emitting diode.
• Pins: cathode, anode

Resistor (220 Ohms)

• Description: A resistor with a resistance of 220 Ohms.
• Pins: pin1, pin2

Resistor (1000 Ohms)

• Description: A resistor with a resistance of 1000 Ohms.
• Pins: pin1, pin2

Piezo Buzzer

• Description: A device that produces sound when an electric signal is applied.
• Pins: pin 1, pin 2

Diode

• Description: A component that allows current to flow in one direction only.
• Pins: cathode, anode

MQ 135

• Description: A gas sensor that detects air quality.
• Pins: D OUT, A OUT, GND, VCC

Tower Pro SG90 Servo

• Description: A small servo motor used for precise control of angular position.
• Pins: Signal, +5V, GND

ESP32

• Description: A microcontroller with integrated Wi-Fi and Bluetooth capabilities.
• Pins: EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, GND, VIN, 3V3, D15, D2, D4, RX2, TX2, D5, D18, D19, D21, RX0, TX0, D22, D23, BOOT

Wiring Details

DC Motor

• pin 1 is connected to:

  • Temperature Sensor (LM35) +Vs
  • Diode cathode
  • ESP32 VIN
  • Tower Pro SG90 Servo +5V
  • MQ 135 VCC

• pin 2 is connected to:

  • NPN Transistor (CBE) collector

Temperature Sensor (LM35)

• +Vs is connected to:

  • DC Motor pin 1

• Vout is connected to:

  • ESP32 VN

• GND is connected to:

  • Piezo Buzzer pin 2
  • LED: Two Pin (red) cathode
  • LED: Two Pin (green) cathode
  • NPN Transistor (CBE) emitter
  • ESP32 GND
  • Tower Pro SG90 Servo GND
  • MQ 135 GND

NPN Transistor (CBE)

• collector is connected to:

  • DC Motor pin 2

• base is connected to:

  • Resistor (1000 Ohms) pin1

• emitter is connected to:

  • Temperature Sensor (LM35) GND

LED: Two Pin (red)

• cathode is connected to:

  • Piezo Buzzer pin 2
  • LED: Two Pin (green) cathode
  • Temperature Sensor (LM35) GND
  • NPN Transistor (CBE) emitter
  • ESP32 GND
  • Tower Pro SG90 Servo GND
  • MQ 135 GND

• anode is connected to:

  • Resistor (220 Ohms) pin1

LED: Two Pin (green)

• cathode is connected to:

  • Piezo Buzzer pin 2
  • LED: Two Pin (red) cathode
  • Temperature Sensor (LM35) GND
  • NPN Transistor (CBE) emitter
  • ESP32 GND
  • Tower Pro SG90 Servo GND
  • MQ 135 GND

• anode is connected to:

  • Resistor (220 Ohms) pin1

Resistor (220 Ohms)

• pin1 is connected to:

  • LED: Two Pin (red) anode

• pin2 is connected to:

  • ESP32 D2

Resistor (1000 Ohms)

• pin1 is connected to:

  • NPN Transistor (CBE) base

• pin2 is connected to:

  • ESP32 D13

Piezo Buzzer

• pin 1 is connected to:

  • Resistor (220 Ohms) pin1

• pin 2 is connected to:

  • LED: Two Pin (red) cathode
  • LED: Two Pin (green) cathode
  • Temperature Sensor (LM35) GND
  • NPN Transistor (CBE) emitter
  • ESP32 GND
  • Tower Pro SG90 Servo GND
  • MQ 135 GND

Diode

• cathode is connected to:

  • DC Motor pin 1

• anode is not connected to any other component.

MQ 135

• D OUT is connected to:

  • ESP32 D18

• A OUT is connected to:

  • ESP32 VP

• GND is connected to:

  • Piezo Buzzer pin 2
  • LED: Two Pin (red) cathode
  • LED: Two Pin (green) cathode
  • Temperature Sensor (LM35) GND
  • NPN Transistor (CBE) emitter
  • ESP32 GND
  • Tower Pro SG90 Servo GND

• VCC is connected to:

  • DC Motor pin 1

Tower Pro SG90 Servo

• Signal is connected to:

  • ESP32 D5

• +5V is connected to:

  • DC Motor pin 1

• GND is connected to:

  • Piezo Buzzer pin 2
  • LED: Two Pin (red) cathode
  • LED: Two Pin (green) cathode
  • Temperature Sensor (LM35) GND
  • NPN Transistor (CBE) emitter
  • ESP32 GND
  • MQ 135 GND

ESP32

• D4 is connected to:

  • Resistor (220 Ohms) pin2

• D2 is connected to:

  • Resistor (220 Ohms) pin2

• D15 is connected to:

  • Resistor (220 Ohms) pin2

• VN is connected to:

  • Temperature Sensor (LM35) Vout

• VIN is connected to:

  • DC Motor pin 1

• GND is connected to:

  • Piezo Buzzer pin 2
  • LED: Two Pin (red) cathode
  • LED: Two Pin (green) cathode
  • Temperature Sensor (LM35) GND
  • NPN Transistor (CBE) emitter
  • Tower Pro SG90 Servo GND
  • MQ 135 GND

• VP is connected to:

  • MQ 135 A OUT

• D5 is connected to:

  • Tower Pro SG90 Servo Signal

• D18 is connected to:

  • MQ 135 D OUT

• D13 is connected to:

  • Resistor (1000 Ohms) pin2

Documented Code

ESP32 Code

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

}

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

}

This code is a basic template for the ESP32 microcontroller. The setup function is where you initialize your components and configurations, and the loop function is where you place the code that needs to run continuously.