MICROVARISTOR-BASED OVERVOLTAGE PROTECTION

A method is disclosed for producing a non-linear powder having microvaristor particles which have a non-linear current-voltage characteristic. The production steps includes mixing non-metallic particles with the microvaristor particles, thermally treating the non-metallic particles for decomposing them into electrically conductive particles and fusing the electrically conductive particles onto the microvaristor particles. Embodiments, among other things, relate to: breaking up agglomerates of the non-metallic particles during mixing; keeping the decomposition temperature below a sintering or calcination temperature of the microvaristor particles; and choosing micron-sized or nano-sized non-conductive particles for microvaristor decoration. The production method produces varistor powder with improved reproducibility of the non-linear electric current-voltage characterstic and with reduced switching fields (Es).