Microcontroller based tester for semiconductor devices

The system presented in this paper represents an enhanced tester for active devices. It ensure the identification of the transistor type (PNP, NPN, JFET, n-MOS, p-MOS) connected to the test terminals, can detect the disposing of the component´s terminals in the package and also can measure the gain factor of the bipolar transistors. In addition, the proposed module can measure the channel resistance of field effect transistors (FET) and threshold voltage for metal-oxide transistors (MOS). The measurement results for the tested device are presented on an LCD display. The system is based on PIC16F872 microcontroller which manage the voltages applied to the three test terminals where is connected the semiconductor device. The system is battery operated. By using the microcontroller technology and very few external components, it is obtained a portable and versatile apparatus that allows quick and accurate measurements on active electronic components.