Circuit Documentation

Summary

This circuit is designed to control a defogging system for a camera lens. It uses a DHT11 humidity sensor to monitor humidity levels near the lens. When the humidity surpasses a threshold, a buzzer sounds and a relay is activated to turn on a fan. The camera module (OV7670) captures images which can be viewed using the serial port reader. The circuit is controlled by an Arduino UNO microcontroller.

Component List

1. 120 Fan 12V

   • Pins: 12V+, GND
   • Description: A 12V fan used for defogging the camera lens.
   • Properties: None

2. Resistor (4700 Ohms)

   • Pins: pin1, pin2
   • Description: A resistor with a resistance of 4700 Ohms.
   • Properties: Resistance: 4700 Ohms

3. Resistor (200 Ohms)

   • Pins: pin1, pin2
   • Description: A resistor with a resistance of 200 Ohms.
   • Properties: Resistance: 200 Ohms

4. Arduino UNO

   • Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0, A1, A2, A3, A4, A5, SCL, SDA, AREF, D13, D12, D11, D10, D9, D8, D7, D6, D5, D4, D3, D2, D1, D0
   • Description: A microcontroller board based on the ATmega328P.
   • Properties: None

5. KY-015 DHT11

   • Pins: 5V, S, GND
   • Description: A humidity and temperature sensor.
   • Properties: None

6. OV7670

   • Pins: RET, PWDN, D1, D0, D3, D2, D4, D5, D6, PLK, XLK, D7, VS, HS, SCL, SDA, 3.3V, DGND
   • Description: A camera module for capturing images.
   • Properties: None

7. Resistor (10000 Ohms)

   • Pins: pin1, pin2
   • Description: A resistor with a resistance of 10000 Ohms.
   • Properties: Resistance: 10000 Ohms

8. 12V Battery

   • Pins: -, +
   • Description: A 12V battery used to power the fan and other components.
   • Properties: None

9. 5V Relay

   • Pins: Normally Open, Common terminal, Normally Closed, In, GND, VCC
   • Description: A relay used to control the fan.
   • Properties: None

10. LM340T5 7805

    • Pins: Vout, Vin, GND
    • Description: A voltage regulator to convert 12V to 5V.
    • Properties: None

11. Buzzer

    • Pins: PIN, GND
    • Description: A buzzer used to alert when the humidity surpasses the threshold.
    • Properties: None

Wiring Details

120 Fan 12V

• 12V+ connected to 12V Battery +
• GND connected to 12V Battery -

Resistor (4700 Ohms)

• pin1 connected to OV7670 DGND
• pin2 connected to OV7670 XLK

Resistor (200 Ohms)

• pin1 connected to Arduino UNO D11
• pin2 connected to Arduino UNO D11

Arduino UNO

• 3.3V connected to OV7670 3.3V
• 5V connected to KY-015 DHT11 5V
• GND connected to OV7670 DGND, KY-015 DHT11 GND, 5V Relay GND, LM340T5 7805 GND, Resistor (4700 Ohms) pin1, Buzzer GND
• A0 connected to OV7670 D0
• A1 connected to OV7670 D1
• A2 connected to OV7670 D2
• A3 connected to OV7670 D3
• A4 connected to Resistor (10000 Ohms) pin2, OV7670 SDA
• A5 connected to Resistor (10000 Ohms) pin2, OV7670 SCL
• D13 connected to Buzzer PIN
• D12 connected to 5V Relay In
• D8 connected to OV7670 HS
• D7 connected to OV7670 D7
• D6 connected to OV7670 D6
• D5 connected to OV7670 D5
• D4 connected to OV7670 D4
• D3 connected to OV7670 VS
• D2 connected to OV7670 PLK
• D1 connected to KY-015 DHT11 S

KY-015 DHT11

• 5V connected to Arduino UNO 5V
• S connected to Arduino UNO D1
• GND connected to Arduino UNO GND

OV7670

• RET connected to OV7670 PWDN, OV7670 DGND, LM340T5 7805 GND, Resistor (4700 Ohms) pin1, Buzzer GND, 5V Relay GND, Arduino UNO GND
• PWDN connected to OV7670 RET
• D0 connected to Arduino UNO A0
• D1 connected to Arduino UNO A1
• D2 connected to Arduino UNO A2
• D3 connected to Arduino UNO A3
• D4 connected to Arduino UNO D4
• D5 connected to Arduino UNO D5
• D6 connected to Arduino UNO D6
• D7 connected to Arduino UNO D7
• PLK connected to Arduino UNO D2
• XLK connected to Resistor (4700 Ohms) pin2
• VS connected to Arduino UNO D3
• HS connected to Arduino UNO D8
• SCL connected to Resistor (10000 Ohms) pin2, Arduino UNO A5
• SDA connected to Resistor (10000 Ohms) pin2, Arduino UNO A4
• 3.3V connected to Arduino UNO 3.3V
• DGND connected to OV7670 RET

Resistor (10000 Ohms)

• pin1 connected to Resistor (10000 Ohms) pin1, OV7670 3.3V, Arduino UNO 3.3V
• pin2 connected to Arduino UNO A4, OV7670 SDA
• pin2 connected to Arduino UNO A5, OV7670 SCL

12V Battery

• + connected to LM340T5 7805 Vin, 120 Fan 12V 12V+, 5V Relay Normally Open, 5V Relay Common terminal
• - connected to 120 Fan 12V GND

5V Relay

• Normally Open connected to 12V Battery +
• Common terminal connected to 12V Battery +
• Normally Closed not connected
• In connected to Arduino UNO D12
• GND connected to Arduino UNO GND
• VCC connected to LM340T5 7805 Vout

LM340T5 7805

• Vout connected to 5V Relay VCC
• Vin connected to 12V Battery +
• GND connected to OV7670 RET

Buzzer

• PIN connected to Arduino UNO D13
• GND connected to OV7670 RET

Code Documentation

/*
 * This Arduino Sketch controls a defogging system for a camera lens.
 * It uses a DHT11 humidity sensor to monitor humidity levels near the lens.
 * When the humidity surpasses a threshold, a buzzer sounds and a relay is
 * activated to turn on a fan. The