Analysis of NPO, c0g, X7R, x5r, Y5V, z5u of SMD Ceramic Capacitors

What is the difference between NPO and X7R, x5r, Y5V, and z5u Shenma?
MainlyDifferent media materials.The main polarization types of different media types are different., Its pairResponse speed of electric field changesAndPolarization RateAlso different. The capacity varies under the same volume, and the dielectric loss and capacity stability of the capacitor are also different. The temperature stability of the media based on capacity can be divided into two types: Class I Ceramic Capacitor and Class II ceramic capacitor,NPO belongs to Class I CeramicsWhile otherX7R, x5r, Y5V, z5u and so on all belong to Class II Ceramics.

 

What are the characteristics of Class I ceramics?
Class I Ceramic CapacitorHigh frequency ceramic capacitor(High-frequency ceramic capacitor ),Medium UsedNon-iron (shundian)RecipeTake TiO2 as the main component (dielectric constant less than 150), so it has the most stable performance; or by adding a small amount of other (iron oxide), such as O3 or srtio, constitute"Extended" temperature compensated CeramicsApproximate Linear Temperature Coefficient, The dielectric constant increases to 500. These two types of media have low loss, high insulation resistance, and good temperature characteristics. It is particularly suitable for oscillator, resonant circuit, coupling capacitance in high-frequency circuit, and other circuits that require low loss and stable electrical capacity, or for temperature compensation. 

How to express the Temperature Characteristics of Class I Ceramics
The temperature and capacity characteristics (TCC) of Class I ceramics are very small, and the Unit is usually in ppm/℃. The variation of the capacity compared with the reference value is often far less than the 1 skin method. The American Electronics Industry Association (EIA) standard uses the "letter + digit + Letter" code form to express class I ceramic temperature coefficient. For example, the common c0g. 

C0gWhat is the temperature coefficient?
C indicates that the effective number of the capacitance temperature coefficient is 0 ppm/℃.
0 indicates that the multiplier factor of the valid number is-1 (that is, the power 0 of 10)
G indicates that the temperature variation tolerance is ± 30ppm

After calculation, the final TCC of the c0g capacitor is 0 × (-1) ppm/℃ ± 30ppm/℃. The temperature coefficient of other class I ceramics, such as the u2j capacitor, is calculated as-750 ppm/℃ ± 120 ppm/℃.

 

NPO and c0g are the same type of capacitors.?
NPO is the term in the US Military Standard (MIL). It should actually be np0 (zero), but we are generally used to writing it as NPO (euro ). This is short for negative-positive-zero, used to represent the temperature characteristics. It indicates that the NPO capacitor has good temperature characteristics and does not drift along with the positive and negative temperature changes.
We already know from the beginning,C0g is one of the best temperature stability in class I ceramics, and its temperature characteristic is approximately 0., Which satisfies the meaning of "negative-positive-zero.SoC0g is actually the same as NPO, But yesTwo standard Representation Methods(Of course, c0k and c0j, which have a smaller capacity and a lower precision, are also NPO capacitors ). Similarly, the u2j corresponds to the group code in the Mil standard as n750.

The characteristics of the NPO capacitor vary with the encapsulation form, and the electrical capacity and dielectric loss change with frequency. The frequency characteristics of the large encapsulation size are better than that of the small encapsulation size.

 

What are the characteristics of Class II ceramics?
Class ⅱ ceramic capacitor was previously calledLow frequency ceramic capacitor(Low frequency ceramic capacitor), usedFerrite CeramicsAs a medium capacitor, it is also called a Ferrite Ceramic Capacitor. This type of capacitor is larger than the capacitor, And the capacitance varies with the temperature.Non-linear variation, large loss, Often used in electronic devicesBypass and CouplingOr usedOther circuits that do not require high loss and low stability of electrical capacity. Among them, Class II ceramic capacitors are classified into stable and available levels.X5r and X7R are stable class II Ceramics, AndY5V and z5u are available.

 

What are the differences between x5r, X7R, Y5V, and z5u?
The main difference lies in the change of temperature range and capacity with temperature. The following table shows the meanings of these codes.

Take X7R as an example.
X indicates that the capacitance can work at-55 ℃ at least.
7 indicates that the capacitor can work at a maximum of + 125 ℃.
R represents the variation of the volume value with the temperature as ± 15%
Similarly, the normal operating temperature of Y5V ranges from-30 ℃ ~ + 85 ℃, the corresponding capacitance capacity changes to + 22 ~ -82%; while the normal operating temperature of z5u ranges from + 10 ℃ ~ + 85 ℃, the corresponding capacitance capacity changes to + 22 ~ -56%.