Ceramic Capacity Noise

When capacitors are used for power supply decoupling they serve two roles.

Ceramic capacity noise.

Piezoelectric noise piezoelectric effect in mlccs multilayer ceramic chip capacitors mlccs multi layer ceramic capacitor have several advantages low equivalent series resistance esr low equivalent series inductance esl small size non polarized a disadvantage of the mlcc can be thepiezoelectric nature of the. Protecting the power source from electrical noise generated within the circuit and protecting the circuit from electrical noise generated by other devices connected to the same power source. Most dielectrics of ceramic capacitors exhibit a characteristic identified as piezoelectric effects than can cause unexpected signals in certain circuits. Capable of replacing 2 or more conventional devices the x2y ceramic capacitors are ideal for high frequency filtering or noise suppression of supply voltages in digital circuits and can prove invaluable in meeting stringent emc demands in dc motors in automotive audio sensor and other applications.

There is almost no noise generated by the capacitor itself. For example the noise sounds like a hum hiss or a high pitched tone. In some cases the piezoelectric effect may result in the appearance of electrical noise while in other cases.