Crystal Oscillator Circuit Design

Circuit and design description march 1 2016 by ajay kumar crystal oscillator is an electronic oscillator used to create an electrical signal of precise frequency by using the vibrating crystal mechanical resonance made of piezoelectric material.

Crystal oscillator circuit design.

Figure 2 4 shows the maximum drive power that can be put into a crystal without excessive heating and frequency shift in the crystal fig ure 2 5 shows the maximum permissible drive voltage across the crystal at exact series resonance. The exact frequency at which an oscillator will operate is dependent on the loop phase angle shifts within the oscillator circuit. In this type of crystal oscillator design the filter consists of the crystal s equivalent model and the external load capacitors. Series resonant oscillator circuits are fairly basic and are typically used because of their small component count.

It consists of ic 4060 and ic 4013 the ic 4060 single acting oscillator and counter. It will create an electrical signal with a given frequency. There s no need for capacitors in the feedback loop for this type of circuit. A series circuit crystal oscillator uses a crystal that s designed to operate at its natural resonant frequency.

These types of oscillator is practically invariably of the l c variety for functioning frequencies of a few hundred khz and above. Changes in the phase angle will result in a change in the output frequency. Of the frequency determined by the resistor and external capacitor. A crystal oscillator is obviously designed to offer high firmness at a single frequency and is useless if a tuneable wide range oscillator is needed.

References and additional reading are listed below. Ever wonder what goes in to the design of a crystal oscillator. My discrete pierce oscillator design tool can be found here. The design of a crystal oscillator is very similar to the design of the colpitts oscillator we looked at in the previous tutorial except that the lc tank circuit that provides the feedback oscillations has been replaced by a quartz crystal as shown below.

It can be used in the normal clock circuit. We ll examine the operational theory of crystal oscillators and design a discrete pierce crystal oscillator suitable for use as a local oscillator in an hf receiver. 3 cd4060 crystal oscillator circuit this is a 1hz oscillator circuit for a standard digital clock frequency size 1 hz or 2 hz. A crystal oscillator is an electronic oscillator circuit that is used for the mechanical resonance of a vibrating crystal of piezoelectric material.