Abstract How to start oscillation and how to stabilize amplitude in SC oscillators are discussed. New methods for start-oscillation and amplitude-stabilization of SC oscillators are presented. The control circuitry with good stability for amplitude-stabilization is given. It is shown that the complexity of the amplitude-stabilization circuitry does not increase as the number of oscillator phases in the multiphase oscillator increases. The experimental results are in agreement with the presented theory.