Control Circuits for Adjustable Digitally Programmed DC Power Supplies

This paper presents and compare two methods for digital output programming and regulation of Switched Mode Power Supplies. One method is based on shunt regulator TL431 emulation, while the other uses injected current into the reference resistor divider. Both methods are tested on LM3481-EVM commercial module and have shown good linearity and satisfactory control performances on output voltage regulation. Finally, control accuracy of the two methods is discussed.