EIA Class 2 dielectric
Encyclopedia
The EIA
Class 2 dielectric materials are ceramic
dielectric
materials used in ceramic capacitors.
The EIA Class 2 dielectrics in general are usually based on formulas with high content of barium titanate
(BT), possibly mixed with other dielectric electroceramics
. Due to its piezoelectric properties, they are subject to microphonics
. Other oxides added can be the same as used for Class 1 ceramics.
s they tend to have severe temperature drift, high dependence of capacitance on applied voltage, high voltage coefficient of dissipation factor, high frequency coefficient of dissipation, and problems with aging due to gradual change of crystal structure. Aging causes gradual exponential loss of capacitance
and decrease of dissipation factor
.
X5R performs better than other dielectrics, such as Y5V, and permits the construction of physically smaller capacitors than other dielectrics, such as NP0 and X7R. Typically its temperature variation of capacitance is +/-15% over a range of -55 to +85 degrees Celsius. The temperature variation is, however, non-linear.
X7R is designed for capacitors with capacity ranging typically between 3.3 nF
to 330 nF (SMT
: 100 pF to 10 µF). Good for non-critical coupling, filtering, transient voltage suppression, and timing applications. Has high dielectric constant
. It is an EIA Class 2 dielectric. Its variation over a temperature range of −55 to +125 °C is ±15%.
Y5P and Y5V are other such class 2 ceramics, with temperature range of −30 to +85 °C and wide capacitance change with temperature of ±10% or +22/-82%. Usually used for capacitances between 150 pF and 2 nF (SMT: 10 nF to 10 µF). Y5P is equivalent to the IEC
code 2B4.
Z5U is commonly found from 2.2 nF to 2.2 µF, 20%. Good for bypass, coupling applications. Low price and small size, poor temperature stability. This is equivalent to the IEC code 2E6.
Electronic Industries Alliance
The Electronic Industries Alliance was a standards and trade organization composed as an alliance of trade associations for electronics manufacturers in the United States. They developed standards to ensure the equipment of different manufacturers was compatible and interchangeable...
Class 2 dielectric materials are ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...
dielectric
Dielectric
A dielectric is an electrical insulator that can be polarized by an applied electric field. When a dielectric is placed in an electric field, electric charges do not flow through the material, as in a conductor, but only slightly shift from their average equilibrium positions causing dielectric...
materials used in ceramic capacitors.
The EIA Class 2 dielectrics in general are usually based on formulas with high content of barium titanate
Barium titanate
Barium titanate is the inorganic compound with the chemical formula BaTiO3. Barium titanate is a white powder and transparent as larger crystals...
(BT), possibly mixed with other dielectric electroceramics
Electroceramics
Electroceramics is a class of ceramic materials used primarily for their electrical properties.While ceramics have traditionally been admired and used for their mechanical, thermal and chemical stability, their unique electrical, optical and magnetic properties have become of increasing importance...
. Due to its piezoelectric properties, they are subject to microphonics
Microphonics
Microphonics describes the phenomenon where certain components in electronic devices transform mechanical vibrations into an undesired electrical signal...
. Other oxides added can be the same as used for Class 1 ceramics.
Comparison to Class 1 dielectrics
In comparison with the EIA Class 1 dielectricEIA Class 1 dielectric
The EIA Class 1 dielectric materials are ceramic dielectric materials used in ceramic capacitors of small values The EIA Class 1 dielectric materials are ceramic dielectric materials used in ceramic capacitors of small values The EIA Class 1 dielectric materials are ceramic dielectric materials...
s they tend to have severe temperature drift, high dependence of capacitance on applied voltage, high voltage coefficient of dissipation factor, high frequency coefficient of dissipation, and problems with aging due to gradual change of crystal structure. Aging causes gradual exponential loss of capacitance
Capacitance
In electromagnetism and electronics, capacitance is the ability of a capacitor to store energy in an electric field. Capacitance is also a measure of the amount of electric potential energy stored for a given electric potential. A common form of energy storage device is a parallel-plate capacitor...
and decrease of dissipation factor
Dissipation factor
In physics, the dissipation factor is a measure of loss-rate of energy of a mode of oscillation in a dissipative system. It is the reciprocal of Quality factor, which represents the quality of oscillation....
.
Marking code
The EIA three-character code is derived from the minimum and maximum temperature limit, and the amount of capacitance change permitted within that range.
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Common types
Although this code can describe a huge number of possible dielectrics, only a few are commonly manufactured.X5R performs better than other dielectrics, such as Y5V, and permits the construction of physically smaller capacitors than other dielectrics, such as NP0 and X7R. Typically its temperature variation of capacitance is +/-15% over a range of -55 to +85 degrees Celsius. The temperature variation is, however, non-linear.
X7R is designed for capacitors with capacity ranging typically between 3.3 nF
Farad
The farad is the SI unit of capacitance. The unit is named after the English physicist Michael Faraday.- Definition :A farad is the charge in coulombs which a capacitor will accept for the potential across it to change 1 volt. A coulomb is 1 ampere second...
to 330 nF (SMT
Surface-mount technology
Surface mount technology is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards . An electronic device so made is called a surface mount device...
: 100 pF to 10 µF). Good for non-critical coupling, filtering, transient voltage suppression, and timing applications. Has high dielectric constant
Dielectric constant
The relative permittivity of a material under given conditions reflects the extent to which it concentrates electrostatic lines of flux. In technical terms, it is the ratio of the amount of electrical energy stored in a material by an applied voltage, relative to that stored in a vacuum...
. It is an EIA Class 2 dielectric. Its variation over a temperature range of −55 to +125 °C is ±15%.
Y5P and Y5V are other such class 2 ceramics, with temperature range of −30 to +85 °C and wide capacitance change with temperature of ±10% or +22/-82%. Usually used for capacitances between 150 pF and 2 nF (SMT: 10 nF to 10 µF). Y5P is equivalent to the IEC
International Electrotechnical Commission
The International Electrotechnical Commission is a non-profit, non-governmental international standards organization that prepares and publishes International Standards for all electrical, electronic and related technologies – collectively known as "electrotechnology"...
code 2B4.
Z5U is commonly found from 2.2 nF to 2.2 µF, 20%. Good for bypass, coupling applications. Low price and small size, poor temperature stability. This is equivalent to the IEC code 2E6.
See also
- EIA Class 1 dielectricEIA Class 1 dielectricThe EIA Class 1 dielectric materials are ceramic dielectric materials used in ceramic capacitors of small values The EIA Class 1 dielectric materials are ceramic dielectric materials used in ceramic capacitors of small values The EIA Class 1 dielectric materials are ceramic dielectric materials...
- EIA StandardsEIA StandardsHere is a list of Electronic Industries Alliance Standards:* RS-170 Name? * EIA-222 Standards for antenna mast structural integrity...
- Ceramic Capacitors