Temperature controller using DS1820 and LCD display

This Project is used to indicate the temperature and it is also used as controller. The system will get the temperature from the DS1820 and it will display the temperature over the LCD display. There are 2 preset levels, one is low preset and the other is High preset. The temperature was compared with the value stored by the user and if the temperature goes beyond the High Preset temperature then an relay is switched ON until the temperature comes below the Low preset temperature.

The System is fully controlled by the microcontroller AT89S52. It is a popular 8 bit microcontroller. The circuit consists of four switches, in which two buttons are used to increment and decrement the High limit temperature value and the other two buttons are used to increment and decrement the Low limit temperature value.

The temperature limits are stored inside the EEPROM, since 89s52 dont have inbuilt eeprom. The IC 24C02 is the eeprom chip and it is connected to the microcontroller through the I2C bus. The DS1820 is the temperature sensor chip which is connected to the microcontroller through 1 wire bus.


Download the microcontroller code and PC application: Temperature-controller