Ceramic Capacitors (Fixed Capacitors)

Ceramic materials work well as dielectrics. Sheets of metal are stacked alternately with wafers of ceramic to make these capacitors. The meshing/layering geometry of following Figure is used. Ceramic, like mica, has low loss and allows for high efficiency.

A cross-sectional drawing of a capacitor consisting of two meshed sets of several metal plates, separated by layers of dielectric material.

For small values of capacitance, only one layer of ceramic is needed, and two metal plates can be glued to the disk-shaped material, one on each side. This type of component is known as a diskceramic capacitor. Alternatively, a tube or cylinder of ceramic can be employed, and metal ink applied to the inside and outside of the tube. Such units are called tubular capacitors. Ceramic capacitors have values ranging from a few picofarads to about 0.5 μF. Their voltage ratings are comparable to those of paper capacitors.