Will capacitors vibrate

What causes a capacitor to vibrate?

The piezoelectric effect can cause ferroelectric capacitors (class II and III with medium to high dielectric constants such as X5R, X7R, X8R, Y5V, Y5U, and Z5U) to vibrate. If this vibration occurs within audible frequencies (20 Hz to 20 kHz), the capacitor may "sing" and be audible.

Why do multilayer ceramic capacitors vibrate?

Abstract: Multilayer ceramic capacitors (MLCC) are present in every electronic device. Unfortunately, due to the dielectric material they are made of, they vibrate in the presence of an electric field. This vibration is transferred to the PCB via the solder joint creating the acoustic noise known as “singing” capacitor phenomenon.

Why do MLCC capacitors vibrate?

Unfortunately, the main dielectric material used for MLCCs, Barium Titanate, makes the capacitors vibrate due to the piezoelectric and electrostrictive effects. This vibration is transferred to the PCB, making it resonate in the audible range of 20 Hz–20 kHz, and in this way the singing capacitors phenomenon occurs.

What causes a singing capacitor?

The vibration is transferred from the inter electrodes to the capacitor terminals, from the terminals to the solder joint, and finally to the PCB, causing the singing capacitor phenomenon .

What is the risk of vibration damage to a capacitor?

There is most risk of vibration damage to capacitors in applications where high μF values are used where the parts are physically large, often with many paralleled. Examples would be in DC-link connections in inverters or motor controllers or output filters in high power AC-DC and DC-DC converters.

How to avoid singing capacitor acoustic phenomena?

The mirror or back-to-back configuration is considered the best solution in the literature. As mentioned before, it is better to prevent than to correct. By simulating the design, we can avoid the apparition of the singing capacitor phenomenon. To simulate the acoustic behavior, we need a harmonic analysis.