An Oscillator Circuit with External Synchronization

Abstract

An oscillator circuit with an external synchronization function belongs to the technical field of electronic circuits. By adding an external resistor in the oscillator circuit, adjusting the size of the external resistor to adjust the frequency of its own oscillator; in addition, a synchronous circuit is added to force the synchronous oscillator frequency through the synchronous control signal SYNC to obtain a stable and reliable clock signal CLK; at the same time Since a constant current source is used to discharge the capacitor of the oscillator, the discharge time, that is, the time when the clock signal CLK is at a high level, is controllable, and there will be no problem that the circuit cannot respond due to too short a high level time of the clock signal CLK. The oscillator circuit proposed by the invention has adjustable oscillation frequency, can realize external synchronization, has high stability, and can effectively suppress problems such as intermodulation interference and electromagnetic interference existing in the circuit.

Description

technical field [0001] The invention belongs to the technical field of electronic circuits, and in particular relates to an oscillator circuit capable of realizing external synchronization. Background technique [0002] In the field of electronic circuit technology, oscillators are usually used to provide stable and reliable clock signals for system circuits to ensure stable and coordinated work of the circuit system. [0003] Traditional oscillator circuits such as figure 1 shown. The circuit is composed of: a charging and discharging capacitor C0, a current limiting resistor R0, a lower limit comparator COMP1, an upper limit comparator COMP2, an RS latch, and a discharge MOS tube MN0. Among them, the non-inverting input terminal of the lower limit comparator COMP1 is connected to the lower limit threshold voltage Vth_L, the inverting input terminal is connected to the upper plate of the capacitor C0, and the output terminal is connected to the R terminal of the RS latch;...

AI Technical Summary

Problems solved by technology

[0005] but for figure 1 Traditional oscillator circuit, its charging and discharging frequency cannot be controlled

Moreover, since each circuit module in the electronic system has its own unique oscillation frequency, there will be problems such as intermodulation interference and electromagnetic interference in the circuit, which may affect the circuit function in severe cases.

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