Design of electronic system with programmable logic levels of digital signals

Ovaj rad opisuje postupak projektiranja elektroničkog sustava u svrhu dobivanja različitih napona logičkih razina koji se dalje mogu koristiti za napajanje osjetljivijih digitalnih sklopova. Rad elektroničkog sustava temelji se na tri digitalna primopredajnika koji imaju ulazni i izlazni krug te dva priključka za napajanje. Na ulazni krug se s mikrokontrolera dovode signali i napajanje u iznosu od 5 V. U sklopovima koji imaju napon napajanja manji od 5 V, logičke razine signala moraju se smanjiti na prikladne razine koje ovise o napajanju. To se obavlja pomoću regulatora koji na izlazu ima spojen promjenjivi otpornik s kojim se, u ovisnosti o vrijednosti otpora, napon mijenja od 1,2 V do 1,8 V. S tim naponom se napaja izlazni krug sklopa. Na kraju su dani rezultati mjerenja kojima je potvrđena ispravnost i rad elektroničkog sustava.This paper describes the design of the electronic system which can be used to get programmable logical voltage levels. This electronic system has three translating transceivers. Each of the translating transceivers consists of the input and output circuit and two connections for supply voltages. The input circuit is supplied with 5 V from a microcontroler which is also used as a signal source. In the circuits that have a supply voltage less than 5 V, logical levels of signals must be reduced to the appropriate levels that depend on the supply voltage. For that purpose a voltage regulator which has a trimmer on its output is used. Depending on the resistence of the trimmer, the voltage can be changed in the range from 1,2 V to 1,8 V. This voltage is used as the supply voltage of the output circuit of the electronic system. The measurements confirm that the designed system is functional