Ceramic dielectric capacitors are available in values up to several μF in the high-K dielectric formulations of X7R and Z5U, at voltage ratings up to 200 V. NP0 (also called COG) types use a lower dielectric constant formulation, and have nominally zero TC, plus a low voltage coefficient (unlike the less stable high-K types).
A capacitor comes with a set of characteristics. All these characteristics can be found in datasheets that are provided by capacitor manufacturers. Now let us discuss some of them. One of the most important one among all capacitor characteristics is the nominal capacitance (C) of a capacitor.
It is easy to find the value of electrolytic capacitors because they are clearly printed with their capacitance and voltage rating. The voltage rating can be quite low (6V for example) and it should always be checked when selecting an electrolytic capacitor.
All capacitors have a tolerance rating that ranges from -20% to +80%. The working voltage is one more important characteristic of all capacitor characteristics. The maximum amount of voltage which is applied to a capacitor without failure during its working life is called as working voltage (WV).
The nominal value of the Capacitance, C of a capacitor is the most important of all capacitor characteristics. This value measured in pico-Farads (pF), nano-Farads (nF) or micro-Farads (μF) and is marked onto the body of the capacitor as numbers, letters or coloured bands.
Smaller ceramic capacitors can have a nominal value as low as one pico-Farad, ( 1pF ) while larger electrolytic’s can have a nominal capacitance value of up to one Farad, ( 1F ). All capacitors have a tolerance rating that can range from -20% to as high as +80% for aluminium electrolytic’s affecting its actual or real value.