US Patent 9584133 Temperature compensated oscillator with improved noise performance

An oscillator system addresses power supply noise and temperature dependence. The system includes a multi-stage regulator circuit that receives a supply voltage and generates a lower voltage oscillator supply voltage that is less noisy than the supply voltage. A charge pump circuit receives the oscillator supply voltage and the oscillator output signal and supplies the regulator circuit with a boosted voltage. A reference generator circuit supplies a reference signal that is used to determine the oscillator supply voltage. The reference signal varies with temperature and is used to offset the temperature coefficient of the oscillator.