BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an oscillator, and more particularly, an oscillator without crystals.

2. Description of the Related Art

The oscillator is one of the widely used circuits, which is utilized to generate a signal with an oscillation frequency for a frequency signal source of each electronic product. Since the present oscillator utilizes crystals for the signal source, the manufacturing cost of the oscillator increases and the circuit of the oscillator is complex.

Accordingly, it is urgent to provide an oscillator without crystals to solve the problem mentioned above.

SUMMARY OF THE INVENTION

To overcome the shortcomings, the present invention discloses an oscillator, including a voltage switching circuit, a voltage adjustment circuit, and a frequency generation circuit. The voltage switching circuit is electrically connected to a first output terminal and a second output terminal, and receives a first output voltage signal and a second output voltage signal generated by the first output terminal and second output terminal, whereby the first output voltage signal and the second output voltage signal switch the first input voltage signal to a first voltage level signal and switch the second input voltage signal to a second voltage level signal. The first voltage level signal is an inverted signal of the second voltage level signal, the first output voltage signal is an inverted signal of the second output voltage signal, and the first voltage level signal is an inverted signal of the second voltage level signal. The voltage adjustment circuit is electrically connected to the voltage switching circuit and receives the first voltage level signal and the second voltage level signal, whereby the first voltage level signal and the second voltage level signal generate a first adjustment voltage signal and a second adjustment voltage signal. The frequency generation circuit is electrically connected to the voltage adjustment circuit and receives the first adjustment voltage signal and the second adjustment voltage signal to generate the first output frequency signal and the second output frequency signal according to the first adjustment voltage signal and the second adjustment voltage signal.

As mentioned above, the oscillator of the present invention can generate an adjustable oscillation frequency without the crystals by the simple circuit. Therefore, the oscillator of the present invention has the advantages including low cost, simple design, and adjustable architecture.

