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The capacitors are there to resonate with the crystal inductance and cause the crystal to oscillate on its fundamental parallel-resonant mode.
The reason that there are two capacitors in series is to create a network that creates a 180 degree phase inversion at resonance, because the amplifier (inverter) has a 180 degree phase inversion between its input and output. This makes the loop gain have a net phase shift of 360 degrees, which is what causes it to oscillate
The difference between a crystal with two capacitors compared to a ceramic resonator is that the capacitors happen to be integrated into the ceramic resonator. From an analysis standpoint, a ceramic resonator is equivalent to a crystal and two capacitors, except that the crystal has a higher Q and better frequency stability.
if ceramic resonator is alternative for crystal and series capacitors, then can i connect ceramic resonator to a microcontroller instead of crystal and series capacitors?
if ceramic resonator is alternative for crystal and series capacitors, then can i connect ceramic resonator to a microcontroller instead of crystal and series capacitors?
Usually yes. Bear in mind that crystals are much more stable and accurate in frequency. This can be very important in timing applications or communications (say, serial port, timers and others).
DC voltage bias between the electrodes can accelerate the initial aging, probably by induced diffusion of impurities through the crystal. Placing a capacitor in series with the crystal and a several-megohm resistor in parallel can minimize such voltages, and hence reduce aging to obtain accurate Oscillations.
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DC voltage bias between the electrodes can accelerate the initial aging, probably by induced diffusion of impurities through the crystal. Placing a capacitor in series with the crystal and a several-megohm resistor in parallel can minimize such voltages, and hence reduce aging to obtain accurate Oscillations.
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