Resistance capacitance (RC) oscillator with low power consumption

Abstract

The invention provides a resistance capacitance (RC) oscillator with low power consumption, which can generate clock control signals with a duty ratio of which the accuracy is increased required by an internal circuit. The RC oscillator comprises a bias circuit, a first inverter, a second n-channel metal oxide semiconductor (NMOS) transistor, a first capacitor, a second inverter, a third NMOS transistor, a second capacitor, a third inverter, a fourth inverter, a fifth inverter, a sixth inverter, an RS trigger, a nor gate and a fourth NMOS transistor, wherein the bias circuit comprises a resister and a first NMOS transistor; a first input end and a second input end of the RS trigger are respectively connected with a first input end and a second input end of the nor gate; the output end of the nor gate is connected with a grid electrode of the fourth NMOS transistor; a first output end of the RS trigger is connected with a drain electrode of the fourth NMOS transistor; and the source electrode of the fourth NMOS transistor is grounded.

Description

technical field [0001] The invention relates to an oscillator in a CMOS integrated circuit, in particular to an RC oscillator with low power consumption, which can generate a clock control signal with improved duty cycle precision required by an internal circuit. Background technique [0002] Commonly used oscillators are generally divided into three types: RC oscillators (ie, resistance-capacitance oscillators), ring oscillators, and crystal oscillators. The RC oscillator has the advantages of short start-up time, easy frequency adjustment, and easy design and manufacture using common CMOS integrated circuit technology. [0003] figure 1 and figure 2 A schematic diagram of a prior art RC oscillator is shown. [0004] Such as figure 1 and figure 2 As shown, the RC oscillator includes a bias circuit, two comparators COMP1 and COMP2, an RS flip-flop and some digital logic. [0005] The bias circuit in the RC oscillator includes a resistor R and a diode-connected NMOS t...

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