Patent ID: 9000852
Filing Date: 2015-04-07
Classification: H03B,H03L

Abstract:
1. A circuit, comprising: a signal amplifying circuit coupled with a crystal component of a natural frequency to form a crystal oscillator; a signal generator circuit configured to generate a signal with an energy distribution about the natural frequency, and provide the signal to the crystal oscillator to assist the crystal oscillator to begin oscillating; a ring oscillator configured to feed back the signal via at least two or more inverters coupled in series to the ring oscillator, each inverter coupled with a group of capacitors, wherein a first capacitor in the group has a first capacitance which is greater than a second capacitance of a second capacitor in the group and wherein the first capacitor is physically adjacent to the second capacitor; and a noise generation control circuit configured to randomly generate control signals to switch on and off the capacitors to the ring oscillator.