A capacitor consists of two conductive metal plates separated by an insulating dielectric.
The dielectric can be made of glass, ceramic, Tantalum oxide, or plastics such as polyethylene or polycarbonate.
Even air can be used as the dielectric.
When the capacitor holds some energy in the form of extra electrons on one plate and electron holes on the other we say that the capacitor is charged.
Farads
Capacitance (C) is the amount of charge per volt of potential that a capacitor holds.
(C =Q/V where Q = coulombs (the unit of charge) and V = Volts)
Capacitance is measured in farads, but most often a small fraction of a farad thus:
* micro-farads uF millionths (10-6) farads
* pico-farads pF (10-12) farads
###L (Three numbers and a letter) Numbers 1 and 2 are value digits.
Number 3 is a multiplier: 0 = × 1, 1 = × 10, 2 = × 100, 3 = × 1000, 4 = × 10,000.
Letter denotes tolerance: J = 5%, K = 10%, L = 20%
##p or ##n Numbers 1 and 2 are value digits.
p denotes pF, n denotes nF.
Letter symbol Tolerance of capacitor
D +/- 0.5 pF
F +/- 1%
G +/- 2%
H +/- 3%
J +/- 5%
K +/- 10%
M +/- 20%
P +100% ,-0%
Z +80%, -20%
Eg: 103J is a 10,000 pF with +/-5% tolerance
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