Almost every electronic device is equipped with oscillators. Ranging from quartz watch, AM radio transmitter, computers, and metal detectors to stun gun, all uses oscillators. To understand the concept of oscillators, it is quite essential to understand their basic functionality. The most common example of oscillators is the pendulum of a clock. If you push on a pendulum to start it swinging, it will oscillate at same frequency and swing back and forth a certain number of times per second.
An oscillator is basically a mechanical or electronic device that works on the theory of oscillation which results from the periodic variation between two things based on changes in energy. There are many types of electronic oscillators; however they work on the same principle. An oscillator always employs a sensitive amplifier whose output is fed back to the input in phase which results in regenerating and sustaining the signal. This is also known as positive feedback.
On the basis of the output signal produced by
oscillators, they are basically categorized into two classes, namely harmonic oscillators and relaxation oscillators. These oscillators are differentiated on the basis of waveform produced i.e. sinusoidal and square waveforms. Harmonic oscillators are used where sinusoidal waveform needs to be generated. Amplifier in harmonic oscillators delivers gain and a resonant circuit supply a back signal to the input. Whereas, relaxation oscillators generate triangular waveform that is usually used in monolithic integrated circuits. These oscillators help to get operational frequencies with least number of external components.
Every electronic device utilizes particular frequency or we can say that every electronic device works at specific frequency. The frequency at which oscillators work is usually determined by
quartz crystal. When a direct current is applied to such a crystal, it vibrates at a frequency that depends on its thickness and on the manner in which it is cut or shaped. Also, some oscillators make use of combinations of inductors, resistors and capacitors to determine the frequency. However, the best stability in oscillators can be obtained through the use of quartz crystals. These are some concepts that need to be understood in order to grasp the basic functionality of oscillators.
