Crystal oscillator is a crystal[trade_no] (quartz) piezoelectric effect that causes oscillation accuracy by using high frequency when using one of the passive components. Sometimes abbreviated as XTAL. Quartz watches, wireless communications, computers and other essential components of modern electronic equipment.
The circuit design of crystal oscillator must provide load capacitance[trade_no]; There are different types of oscillator electronic circuits used, namely: linear oscillator Hartley oscillator, phase shift oscillator, Armstrong oscillator, Clapp oscillator, Colpitts oscillator. Relaxation oscillator – Royer oscillator, ring oscillator[trade_no], multivibrator [trade_no]and voltage controlled oscillator (VCO).
Quartz crystal[trade_no] has a very important characteristic, which is called piezoelectric effect. When mechanical pressure is applied to the crystal surface, a voltage proportional to the mechanical pressure appears on the crystal. This voltage will cause crystal distortion. The amount of distortion will be proportional to the applied voltage and to the AC voltage applied to the crystal, causing the crystal to vibrate at its natural frequency.
A voltage is applied to the piezoelectric element of the quartz crystal (Application of an electric field), and the deformation occurs in the piezoelectric body. Jacques and Pierre Curie, the discoverers of this phenomenon, are brothers. Electrical performance is usually a capacitor as its natural frequency near a specific frequency band only coil as inductive reactance. The electronic component applying this principle is a crystal resonator[trade_no].
Due to the size of the crystal, many crystal oscillators actually used are about 1-20 MHz. When a higher frequency is required, overtone oscillation will be performed (or a crystal unit for high frequency can be used for overtone), or a frequency multiplier will be used.
