As typical electrical tests may not detect internal flaws such as voids, cracks, de-laminations and electrode discontinuities, which can lead to latent and/or catastrophic failures in high power applications, Passive Plus, Inc. (PPI) offers the following high reliability screening for multilayer ceramic capacitors in production, at no extra charge:
100 percent automated sonoscan (CSAM) inspection on all larger case sizes. Performed on AQL basis for 0505 and 1111 case sizes. The primary benefit of 100 percent CSAM internal inspection is increased reliability, by screening out electrically undetectable internal defects such as voids, cracks, de-laminations or electrode discontinuities.
100 percent high voltage partial discharge testing on all leaded 2225 and larger case size capacitors; Partial discharge testing detects faint electrical discharges in multilayer ceramic capacitors under high voltage conditions. Unacceptably high levels of discharge indicate the presence of large or numerous voids internal to the capacitor, or other possible surface defects, which can lead to immediate or latent catastrophic failures. Low or zero levels of discharge indicate a robust and reliable dielectric structure, ensuring reliability under high stress conditions.
100 hour burn-in on all leaded 1111 and larger case size capacitors and assemblies ensures reliability; The PPI burn-in is done at extended voltage and 125°C, with capacitance, dissipation factor (inverse of Q), and insulation resistance measurements taken before and after burn in.