ELECTRONIC PRINCIPLES - OD1647 - LESSON 1/TASK 1
Mica is an excellent dielectric and can withstand a higher
voltage than can a paper dielectric of the same thickness.
Common values of mica capacitors range from approximately 50
picofarads to 0.02 microfarads. Some different shapes of mica
capacitors are shown in figure 42, view B, on the previous page.
(3) Ceramic Capacitors. A CERAMIC CAPACITOR is so named
because it contains a ceramic dielectric. One type of ceramic
capacitor uses a hollow ceramic cylinder as both the form on
which to construct the capacitor and as the dielectric material.
The plates consist of thin films of metal deposited on the
ceramic cylinder.
A second type of ceramic capacitor is manufactured in the shape
of a disk. After leads are attached to each side of the
capacitor, the capacitor is completely covered with an
insulating moistureproof coating. Ceramic capacitors usually
range in value from 1 picofarad to 0.01 microfarad and may be
used with voltages as high as 30,000 volts. Some different
shapes of ceramic capacitors are shown in figure 43.
FIGURE 43. CERAMIC CAPACITORS.
(4) Electrolytic Capacitors. An ELECTROLYTIC CAPACITOR is
used where a large amount of capacitance is required. As the
name implies, an electrolytic capacitor contains an electrolyte.
This electrolyte can be in the form of a liquid (wet
electrolytic capacitor). The wet electrolytic
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