This paper aims to present a mathematical model of a DC-DC boost converter based on index matrices. The last ones represent electronic components, electrical nodes and loops, and also a switching topology as a result of summation of index matrices of different sizes on such entities. The proposed methodology is shown to be extendable to wide class of electronic devices. Arrangement of rows and columns in usual matrices is substituted by proper index sets. Index matrices with real number elements are used in matrix equations in order voltage and amperage values to be obtained in step-wise manner.