This master’s thesis is about design and realization of a digital controlled power supply. In the introduction there is defined a basic princip and division of the power supplies. Furthermore, there are considered two design realisations of digital controlled power supllies. The first one will be controlled by D/A converter and the second one will be controlled by digital potentiometers. Consequently, there is in the master’s thesis designed controlled part which controls output parameters of supply. The core of the controlled part is microcontroller ATmega16. Output parameters are displayed on LCD display and are set by 4x4 matrix keypad. In the last part there is designed connection between PC and microcontroller by the help of converter FT232BM. Subsequently, there is designed the rectifier with a filter and electronic switching of the fan. At the end of the thesis is resolved the placement of the various component parts to the component box.

This master´s thesis deals with the design of the control circuits for digital potentiometers and their application in analog systems. Digital potentiometers are three-terminal resistors with an adjustable center connection. The digital potentiomneters enable to drive logic gates, LED drivers, LCD drivers, analog switches etc. Controlling of these mentioned devices is possible by the I2C 2- wire serial bus (invented by Philips). The digital potentiometers are used to control of the primary parameters like cut-off frequency and quality factor in the state variable filter and cut-off frequency in a passive filter. Both filters are simulated in PSpice and then compared with the measured results. Next parts of this master's thesis are a computer program and a exemplary protocol.