In the electronics industry, the thermal testing of semiconductor devices is becoming increasingly important. This kind of measurements requires the use of a thermostat unit. In my thesis I describe the design and implementation of a thermostat system designed for such applications. The thermostat has 4 Peltier modules, and 5 thermistor-based temperature sensors. This thermostat has several hardware units including the switched-mode power supply which drives the Peltier modules, and the temperature measurement unit. There is a device measurement board as well, which can measure the characteristics of a diode. The complete system is able to do automated tests, measure the device voltage at different temperatures and device currents.
I summarize the results of research of the related scientific literature. I describe the theoretical basis of the PID controlling, the switched-mode power supplies, and the temperature measurement.
I give a description of the characteristics and functions of the components of this thermostat. I describe the design steps of the hardware units, and their results. I present the development of the firmware of the microcontrollers in the system, their functions and the solutions I used.
The operation of the thermostat, and the created automated test have been verified by measurements. In the last section of my work I show a comparison of the results and make a final evaluation.