The DS18B20 sensor has 3 pins (from right to left): VCC (or VDD), data and GND where: VCC is connected to Arduino 5V and GND is connected to Arduino GND.

The DS3231 RTC module SDA (serial data) and SCL (serial clock) pins are respectively connected to Arduino A4 and A5 pins (ATmega328P hardware I2C module pins). The digital pins 10, 11, 12 and 13 are hardware SPI module pins of ATmega328P microcontroller (Arduino UNO microcontroller). The last pin of the micro SD card module (CS) is connected to Arduino digital pin 10. The fifth pin of the micro SD card module (SCK) is connected to Arduino digital pin 13. The fourth pin of the micro SD card module (MOSI) is connected to Arduino digital pin 11. The third pin of the micro SD card module (MISO) is connected to Arduino digital pin 12. The second pin of the micro SD card module (VCC) is connected to Arduino 5V. The first pin of the micro SD card module (GND) is connected to Arduino GND. The microSD card module is connected to the Arduino as follows (from left to right):

Also this module contains an IC which is 74LVC125A and it’s used as level translator (from 5V to 3.3V). This module contains AMS1117-3V3 voltage regulator which is used to supply the SD card with 3.3V. In this project I used micro SD card module, this module is supplied from circuit 5V source that comes from the Arduino UNO board. The image below shows project hardware circuit diagram.

10k ohm variable resistor or potentiometerĪrduino temperature data logger with SD card circuit:.

DS18B20 temperature sensor -> datasheet.

micro SD card with FAT16 or FAT32 file system.

Arduino UNO board -> Atmega328P datasheet.

This is a list of all components required to build this project. To see how to interface Arduino with DS18B20 sensor, take a look at this post:ĭigital thermometer using Arduino and DS18B20 sensor To see how to interface the Arduino with SD card, visit the following post:Īrduino and SD card example – Read and write files

Time, date and temperature values are displayed on 20×4 LCD screen and sent to PC serial monitor. The DS3231 real time clock chip is used to get time and date information. The Arduino reads temperature from the DS18B20 sensor and saves them (with date and time) to a text file stored on the SD card. This Arduino project shows how to build a temperature data logger using SD card, DS18B20 digital temperature sensor and DS3231 real time clock board.

Arduino log data to file