Circuit Documentation

Summary

The circuit in question is designed to interface an Arduino 101 with a variety of components including a 5V relay, a DS18B20 temperature sensor, a 0.96" OLED display, and a 40mm 12V fan. The circuit is powered by a 12V power supply. The Arduino 101 controls the relay, which in turn controls the power to the fan. The temperature sensor provides input to the Arduino, which can be displayed on the OLED. The relay's operation is likely tied to the temperature readings, allowing for automated control of the fan based on the temperature data.

Component List

Arduino 101

• Microcontroller board based on the Intel Curie module.
• Provides I/O pins for interfacing with various components and sensors.
• Capable of PWM output, I2C communication, and analog input.

5V Relay

• An electromechanical switch that allows a low-power signal to control a higher power circuit.
• Has a Normally Open (NO) and a Normally Closed (NC) contact, along with a common terminal.

DS18B20 Temperature Sensor

• A digital temperature sensor that provides 9-bit to 12-bit Celsius temperature measurements.
• Communicates over a 1-Wire bus that requires only one data line (and ground) for communication.

0.96" OLED Display

• A small display that can show text and graphics in monochrome.
• Interfaces with the Arduino via I2C communication.

40mm 12V Fan

• A standard cooling fan used in electronics and computer applications.
• Operates on 12V DC power.

12V Power Supply

• Provides the necessary 12V DC power to the fan and the relay's common terminal.

Resistor

• A 200 Ohm resistor used likely for pull-up or pull-down purposes in the circuit.

Wiring Details

Arduino 101

• A5/SCL connected to OLED SCK for I2C clock.
• A4/SDA connected to OLED SDA for I2C data.
• D9 PWM connected to Relay In for relay control.
• D2 connected to DS18B20 signal through a 200 Ohm resistor.
• 5V connected to DS18B20 vcc, Relay VCC, and OLED VDD.
• GND connected to DS18B20 GND, Relay GND, and OLED GND.

5V Relay

• Normally Open connected to Fan +12V.
• Common terminal connected to 12V Power Supply +.
• In controlled by Arduino D9 PWM.
• GND shared with Arduino.
• VCC connected to Arduino 5V.

DS18B20 Temperature Sensor

• signal connected to Arduino D2 through a 200 Ohm resistor.
• GND shared with Arduino.
• vcc connected to Arduino 5V.

0.96" OLED Display

• GND shared with Arduino.
• VDD connected to Arduino 5V.
• SCK connected to Arduino A5/SCL for I2C clock.
• SDA connected to Arduino A4/SDA for I2C data.

40mm 12V Fan

• +12V connected to Relay Normally Open.
• -12V connected to 12V Power Supply -.

12V Power Supply

• + connected to Relay Common terminal.
• - connected to Fan -12V.

Resistor

• pin1 connected to DS18B20 vcc.
• pin2 connected to DS18B20 signal and Arduino D2.

Documented Code

No code was provided for the microcontroller. The expected code would handle reading temperature data from the DS18B20 sensor, controlling the relay based on temperature thresholds, and displaying the temperature on the OLED screen. It would also include setup for I2C communication and possibly debounce logic for the relay control.