DIGITAL THERMOMETER CIRCUIT SCHEMATIC DIAGRAM

DIGITAL THERMOMETER CIRCUIT SCHEMATIC DIAGRAM

At this thermometer circuit, the sensor (S8100) or diode (1S1588) is used as the thermo sensor. When using the IC thermo sensor, the thermometry to +100°C from -40°C is possible. Also, when using the diode, the measurement to +150°C from -20°C is possible. Both sensors are contained in the kit.

This time, the thermometer circuit used the diode as the thermo sensor to measure more than +100°C. ICL7136 is used for the thermometer and is measuring the change of the forward direction minute voltages of the diode by the temperature. The 3-1/2 digits liquid crystal display (SP521PR) is used for the display. The most significant digit can display only "1".

The consumption electric power of ICL7136 is very small and it is possible to operate about 3 months continuously with the 9-V cell.