100 years of Colpitts Oscillators: Ontology Review of Common Oscillator Circuit Topologies

The year 2018 marked 100 years since the introduction of a class of oscillatory circuits called Colpitts oscillators. Few other electronic circuits have survived for such a long time and affected the electronic technology as the Colpitts oscillator. Today, Colpitts oscillators are found in both communication systems and digital circuits as clock and frequency generators. In this paper, we provide a comprehensive overview over the development of the Colpitts oscillator, from the simple vacuum tube oscillator patented by Colpitts in 1918, to state of the art MEMS oscillators operating at high GHz region in today?s modern electronics. We review different types of Colpitts oscillators, including singleended, differential, complementary, gm-boosted and introduce a timeline for the development of these circuits.