Comparison of Two Different High Performance Mixed Signal Controllers for DC/DC Converters

Abstract

Mixed signal controllers based on a cheap microcontroller and a few analogue components can deliver high performance digital control of DC/DC converters through an optimized software design. The mixed signal controllers have the same versatility as DSP controllers and can be adapted to any DC/DC converter topology and application. A comparison, both theoretically and experimentally, of two different mixed signal controller designs based on the same 8-bit microcontroller is presented for a low voltage Buck converter. A 16-bit digital PID controller using lookup tables with a sampling frequency as high as 200 kHz implemented on the 16 MIPS, 8-bit ATTiny26 microcontroller is demonstrated and an exhaustive description of the software is given