Classification of oscillation circuits
Oscillator can be divided into two categories: one is a sine wave oscillator, and its output waveform is a sine wave, which is extremely versatile. Such as sine wave signal generator of various frequencies, local oscillator, carrier oscillator and so on. The other type is a non-sinusoidal oscillator whose output waveform is obviously not a sine wave but contains abundant harmonics. Such as square wave, apex pulse, sawtooth wave, triangular wave and so on. They are widely used in counting, timing, and RC oscillator circuits and crystal oscillators.