This project shows the temperature on a three digit 7-segment display, it measures the temperature from -9.5 to 99 degrees Celcius in 0.5 C steps, or from 0 to 210 degrees Fahrenheit in 1.0 degrees steps. Because of the LED display the temperature is also readable in the dark.
The LM35 of National Semiconductors that is used in this project is a precision centigrade temperature sensor, which has an analog output voltage. It has a range of -55潞C to +150潞C and a accuracy of 卤0.5潞C . The output voltage is 10mV/潞C . The output voltage is converted by the AD convertor of the AT Mega8. The temperature is displayed on an LCD module. In this example the thermometer has a range of 0潞C to 40潞C and a resolution of 0.5潞C. If you want to have a readout in Fahrenheit you can use the LM34.
