A crystal oscillator uses a crystal to develop some electrical signal at a certain frequency. When mechanical pressure is applied on the crystal, it produces an electrical signal across its terminals with a certain frequency.
The crystal oscillators are used to provide stable and accurate radio frequency signals. One of most common circuits is used for crystal oscillators is the colpitts circuit. They are basically used in digital systems to provide clock signals.
The crystal operates in parallel resonant mode and generates output signal. The capacitor divider network of C1 and C2 provide the feedback path. The capacitors also form the load capacitance for the crystal. This oscillator can be biased in common emitter or common collector modes. Here the common emitter configuration is used.
A resistor is connected between the collector and source voltage. The output is obtained from the emitter terminal of the transistor through a capacitor. This capacitor acts as a buffer to ensure that the load draws minimum current.
So these are the basic circuits you will encounter in any electronic project. I hope this article has given you ample knowledge. So there is this little task for you. For all the circuits I have listed above, there are alternatives.
