Electronic – What are quartz crystal oscillators

basiccomponentscrystaloscillator

I'm a beginner in electronics and I found two quartz crystal oscillators, each one has two pins. Their numbers are:

sjc4.000a
ee4.000

Is it possible to know the frequency by knowing the numbers? If not, how can I know the frequency?

How do I use them in a very simple circuit?

Best Answer

Quartz crystal is not the same thing as crystal oscillator.

Quartz crystal consists of real physical crystal that has precise dimensions. The higher the desired frequency, the smaller the crystal must be. So it is practical to make them only in certain range (common values are 4 MHz - 40 MHz, and then low-frequency 32 kHz for RTCs).

It works by piezoelectric principle. Applied voltage causes it to contract and vice versa. At certain frequency, it gets into mechanical resonance which is projected into electrical resonance.

Quartz crystal oscillator is circuit that contains a quartz crystal and produces periodic signal. It can be integrated or constructed from individual components. One example is single-inverter oscillator.

pic

The part numbers you provided are almost certainly form an 4MHz crystal.