Different types of dielectric materials have varying responses to electric field changes due to their distinct polarization mechanisms. This leads to differences in capacitance, dielectric loss, and stability under the same volume. Based on temperature stability, ceramic capacitors are generally divided into two categories: Class I and Class II. Class I ceramics, such as NPO, offer high stability and low loss, making them ideal for high-frequency applications. On the other hand, Class II ceramics like X7R, X5R, Y5V, and Z5U provide higher capacitance but with less stable performance over temperature.
Class I ceramic capacitors, also known as high-frequency capacitors, are made from non-ferroelectric or paraelectric materials, typically containing titanium dioxide (TiOâ‚‚) with a dielectric constant below 150. These capacitors exhibit excellent stability, low loss, and high insulation resistance, making them suitable for applications requiring precise and stable capacitance, such as oscillators and resonant circuits. Some Class I ceramics, like C0G, may include small amounts of ferroelectric oxides to slightly increase the dielectric constant while maintaining linear temperature characteristics.
The temperature coefficient of Class I capacitors is usually expressed in parts per million per degree Celsius (ppm/°C). For example, the EIA standard uses codes like C0G, where "C" indicates a zero temperature coefficient, and "G" represents a tolerance of ±30 ppm. This means that the overall temperature coefficient is effectively 0 ± 30 ppm, providing exceptional stability. Other codes, such as U2J, indicate different coefficients, like -750 ± 120 ppm, which are still considered Class I but with slightly lower precision.
NPO and C0G are essentially the same type of capacitor, though they come from different standards. NPO is a military designation (MIL), often written as NP0, while C0G follows the EIA standard. Both represent capacitors with near-zero temperature coefficient, meaning their capacitance remains stable across a wide temperature range. Other similar codes like C0K or C0J also fall under this category, offering slightly smaller capacitances but still maintaining good stability.
Class II ceramic capacitors, commonly referred to as ferroelectric capacitors, are designed for applications where high capacitance is needed, even if stability is compromised. These capacitors have larger dielectric constants and nonlinear temperature characteristics, resulting in greater dielectric loss. They are often used for bypassing, coupling, or filtering in low-frequency circuits. Class II capacitors are further divided into stable grades (like X7R and X5R) and general-purpose grades (like Y5V and Z5U).
The main difference between X5R, X7R, Y5V, and Z5U lies in their operating temperature ranges and the degree of capacitance variation. For instance, X7R operates from -55°C to +125°C with a maximum capacitance change of ±15%, while Y5V has a narrower range (-30°C to +85°C) and a much larger variation (±22% to -82%). Z5U offers a moderate range (+10°C to +85°C) with a variation of ±22% to -56%. Choosing the right type depends on the specific application's requirements for stability and temperature range.
HE series hood is suitable to small heavy duty connectors, it is widely used in machinery, wind energy, rail transportation, power systems, photovoltaic industry, communications industry, engineering equipment and other fields. Heavy Duty Connector is designed for modular production pre-wiring and satisfying severe environmental conditions, applied in rail transit,industrial automation and equipment manufacturing fields. Compared with traditional wiring methods,use of heavy duty connector can reduce site wiring operation after equipment or vehicle leaves the workshop,enhance production efficiency and reduce quality risk of site wiring.
He Series Connector,32 Pin Heavy Duty Connector,32Pin Rectangular Connector,500V Heavy Duty Connector
Kunshan SVL Electric Co.,Ltd , https://www.svlelectric.com