On-chip rc oscillator, chip, and communication terminal

Abstract

Disclosed are an on-chip RC oscillator, a chip, and a communication terminal. The on-chip RC oscillator comprises a stabilized voltage supply module, an RC core oscillator module, a frequency sampling and conversion module, and a frequency trimming module. By means of the frequency sampling and conversion module, the clock frequency of the oscillator is sampled and detected in real time, and the sampled clock frequency is converted into a voltage signal, and then analog-to-digital conversion is performed to obtain a corresponding digital code, so that when the clock frequency changes, the frequency trimming module circuit converts said digital code into a control signal; a voltage having a suitable temperature coefficient is outputted for the RC core oscillator module; also, a zero temperature coefficient current of a suitable magnitude is outputted for the RC core oscillator module, so as to precisely calibrate the clock frequency.