From printed circuit boards to systems-on-a-chip

This paper reviews the technical evolution of one episode in the development of systems manufactured on printed circuit boards to systems realized on an IC (Integrated Circuit) chip. The replacement of LC filters by inductorless circuits is anything but trivial, and is the reason why the replacement of discrete-component LC filters by filters on a semiconductor chip took many decades to achieve. In fact, LC filters were among the last holdouts in the process of replacing discrete-component printed-circuit boards by IC system chips.