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Practical Electronics/Finding component information/Capacitors

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Ceramic Numbering Code

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Generally, they use an alphanumeric marking system. The number part is the same as for SMT resistors, except that the value represented is in pF. They may also be written out directly, for instance, 2n2 = 2.2 nF. For capacitors the tolerance code is:

Tolerance Code Tolerance
A ± 0.05 pF
B ± 0.1 pF
C ± 0.25 pF
D ± 0.5 pF
E ± 0.5%
F ± 1%
G ± 2%
H ± 3%
J ± 5%
K ± 10%
L* ± 15%
M ± 20%
N* ± 30%
P* −0% +100%
S* −20% +50%
W* −0% +200%
X* −20% +40%
Z −20% +80%

letters with * are not used consistently.

how similar is this to resistors?

For example, .047K = .047 µF 10%.

The dielectric material is sometimes designated by another code: (note: the materials in the table below are not ceramic capacitors as implied, but plastic and paper)

Marking Material
KT Polyester Film / Foil
MKT Metallized Polyester (PETP)
KC Polycarbonate Film / Foil
MKC Metallized Polycarbonate
KS Polystyrene Film / Foil
KPS foil/pps?
MPS Metallized pps
KP Polypropylene Film / Foil
MKP Metallized Polypropylene
MP Metallized paper

Please note that the table above is valid most of the time but not always because it is not a real standard. To be real sure you may check the data sheet from the manufacturer in mind.

The cap color can also indicate the dielectric:

Black Brown Red Orange Yellow Green Blue Violet Red/Orange Orange/Orange Yellow/Orange Green/Orange Blue/Orange Red/Violet
C0G/NP0 N030 N080 N150 N220 N330 N470 N750 N1000 N1500 N2200 N3300 N4700 P100

more info at http://my.execpc.com/~endlr/markings.html

Axial ceramic capacitors

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These often have a yellow body, and use the same color band system as resistors, except that the value indicated is in pF.

Multilayer Ceramic capacitors

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These usually use the same alphanumeric system.