Relaxation oscillator and electronic device

Abstract

The invention provides a relaxation oscillator and an electronic device. The relaxation oscillator comprises: a charge and discharge unit; a switch unit, configured to control the charge and dischargeunit to charge and discharge periodically; a comparator unit, configured to compare the voltage on the charge and discharge unit with a reference voltage; and a trigger unit, configured to generate an oscillating signal based on an output signal of the comparator unit and output the oscillating signal to the switch unit to control the charge and discharge unit to charge and discharge periodically; wherein the comparator unit uses a hysteresis comparator, the hysteresis voltage of the hysteresis comparator is Vh, the swing voltage of voltage signals on the charge and discharge unit is Vs, thecycle when the relaxation oscillator works is T, and the reaction time t of the trigger unit satisfies: Vh > 2Vs x t / T. The relaxation oscillator can eliminate self-excitation of a potential fast feedback loop, so that the stability of the relaxation oscillator is improved. The electronic device has similar advantages.

Description

technical field [0001] The invention relates to the technical field of semiconductor integrated circuits, in particular to a relaxation oscillator and an electronic device. Background technique [0002] In many integrated circuit applications, the clock generation circuit is an essential module. According to the requirements of different application scenarios, there are many types of clock generation circuits. figure 1 Shows a common clock generation circuit: the relaxation oscillator. Such as figure 1 As shown, the relaxation oscillator 100 includes capacitors C1, C2, four MOS transistors M1-M4, comparators 101 and 102, and an oscillating circuit composed of an RS flip-flop 103, and a current source and a voltage source 104 provide a reference current for the oscillating circuit Ir and reference voltage Vr, the latch 103 includes two inverters 1030 and 1031 . figure 1 The relaxation oscillator 100 shown uses a current source to periodically charge and discharge capacitor...

AI Technical Summary

Problems solved by technology

But there are at least two disadvantages in doing so: 1) During normal operation, the delay introduced by the comparator's slow response is to be calculated in the total output, and the delay has a greater impact on high-frequency clock output

2) This phenomenon is not completely eliminated, but the probability of this phenomenon is reduced

Images