Analysis of Common Problems of Vacuum Capacitors

What is a capacitor failure?

Capacitors are common on distribution systems and fail relatively often. Capacitor failures can cause other devices on the same circuit or other circuits to fail. Capacitor failures demonstrate important lessons for design of waveform analytics systems. Capacitor switching is generally controlled based on time of day, temperature, and / or voltage.

What are the common failure modes of capacitors?

Common and less well known failure modes associated with capacitor manufacture defects, device and product assembly problems, inappropriate specification for the application, and product misuse are discussed for ceramic, aluminium electrolytic, tantalum and thin film capacitors.

Do capacitor defects contribute to infant and latent failures in integrated circuits?

Capacitor defects significantly contribute to infant and latent failures in integrated circuits. This paper will address methods of locating capacitor defects and root cause determi-nation. Keysight Technologies’ failure analysis team investigated tens of failures in an externally purchased voltage controlled oscillator (VCO).

Do thin film capacitors fail?

In this respect the widest variety of failure modes are associated with thin film capacitors, and many of these failure modes are difficult to screen by using burn in tests, and in some cases even using accelerated stress testing.

What happens if a capacitor fails in open circuit mode?

The open circuit failure mode results in an almost complete loss of capacitance. The high ESR failure can result in self heating of the capacitor which leads to an increase of internal pressure in the case and loss of electrolyte as the case seal fails and areas local to the capacitor are contaminated with acidic liquid.

Why are capacitor failures important in waveform analytics?

Capacitor failures demonstrate important lessons for design of waveform analytics systems. Capacitor switching is generally controlled based on time of day, temperature, and / or voltage. Line capacitors typically switch ON and OFF one, or perhaps two times per day.