Ceramic Resonator Oscillator Circuit

Before we look at the ceramic and crystal resonators let s take a look at the lc oscillator so we need a coil and capacitor.

Ceramic resonator oscillator circuit. Remember from the inductance meter tutorial that an lc tank will resonate at its natural frequency. In a colpitts circuit an inversion of 180 is used and it is inverted more than 180 with l and c in the feedback circuit. The most common oscillator circuit for a ceramic resonator is a colpitts circuit. On the left the crystal right the ceramic resonator.

The table briefly describes the characteristics of various oscillator elements. The active part which makes the oscillator work is an amplifier which supplies the energy to keep the oscillation going. The design of the circuit. A 7 mhz oscillator with a variable crystal oscillator vxo operates very stably but it allows only a small frequency variation approx.

Highly stable oscillation circuits can therefore be made without the need of adjustment. 5 4 equivalent circuit for a ceramic resonator in the frequency range of fr f fa fig. What is a ceramic resonator. The crystal oscillator and ceramic resonator are both electronic oscillator circuits.

Unlike rc or lc circuits ceramic resonators use mechanical resonance. 5 3 electrical equivalent circuit for a ceramic resonator fig. These frequencies are utilized in many ways for their measurement of wavelength. 5 5 impedance and phase characteristics for ceramic resonators fig.

They both use mechanical resonance from piezoelectric material like quartz crystal and ceramics and both create electrical signals of frequency when energized. The material can have two or more electrode which when connected to an oscillator circuit gets mechanical. Vfo with ceramic resonator. Another oscillating circuit is the one that use resonators.

When connected in an electronic oscillator circuit resonant mechanical vibrations in the device generate an oscillating signal of a specific frequency like the similar quartz crystal they are used in oscillators for purposes such as generating. Hartley circuit in a ceramic resonator oscillator the inductor is replaced by a ceramic resonator taking advantage of the fact that the resonator becomes inductive between resonant and anti resonant frequencies. A ceramic resonator is an electronic component consisting of a piece of a piezoelectric ceramic material with two or more metal electrodes attached. See that tutorial for more information.

The most commonly used circuit is the colpitts circuit. In contrast a vfo with an lc resonant circuit can be tuned over a range of several hundred khz but its frequency stability will depend upon its construction. This means it is not basically affected by external circuits or by the fluctuation of the supply voltage. 5 6 spurious characteristics for a typical ceramic resonator csb455e fig.

The operation with a ceramic resonator can be considered as the same. The resonator or crystal itself has two connections. 5 7 basic configuration for an lc oscillation.