Relaxation oscillator

Abstract

The invention provides a relaxation oscillator which comprises a reference current / voltage generator, a capacitor, a first comparator, a second comparator, a latch, and a temperature compensation circuit. The reference current / voltage generator generates first bias current, first bias voltage, and second bias voltage. The capacitor carries out charging based on the charging current generated by the first bias current, and charging voltage is generated. The first comparator compares the charging voltage and the first bias voltage and generates a first comparison result. The second comparator compares the charging voltage and the second bias voltage and generates a second comparison result. The latch generates a clock signal based on the first comparison result and the second comparison result. The clock signal is used for controlling the charging and the discharging of the capacitors, and the frequency of the clock signal is the output frequency of the relaxation oscillator. The temperature compensation circuit senses a temperature change and adjusts the bias current of the first comparator and the second comparator based on the sensed temperature change.

Description

technical field [0001] The present invention relates to the field of circuits, and more particularly relates to a relaxation oscillator. Background technique [0002] There are many types of oscillators, one of which is an RC oscillator with an odd number of stages of amplifiers. A traditional RC oscillator generates a periodic clock signal by charging or discharging a capacitor, and its output frequency depends on the RC time constant. However, because the output frequency of the traditional RC oscillator is often affected by semiconductor process changes and external temperature, and contains large errors, the traditional RC oscillator is not suitable for scenarios that require a more accurate output frequency. Contents of the invention [0003] The present invention provides a novel relaxation oscillator. [0004] A relaxation oscillator according to an embodiment of the present invention includes: a reference current / voltage generator, a capacitor, a first comparator...

AI Technical Summary

Problems solved by technology

However, because the output frequency of traditional RC oscillators is often affected by semiconductor process changes and external temperature, and contains large errors, traditional RC oscillators are not suitable for scenarios that require more accurate output frequencies

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