pcb factory: four classifICations and characteristics of chip capacitors
SMD capacitor is calLED multilayer chip ceramic capacitor, which is equivalent to an insulator. It can open circuit in DC circuit and is one of the most commonly used electronIC components in SMT processing industry. Chip capacitors are mainly divided into NPO capacitors, X7R capacitors, Z5U capacitors and Y5V capacitors. The difference between them is mainly due to the different filled media. With the same volume, the capacity of capacitors formed by different filled media is different, and the resulting dielectric loss and capacity stability of capacitors are also different. Therefore, different capacitors shall be selected according to their different functions in the circuit
SMD capacitor is called multilayer chip ceramic capacitor, which is equivalent to an insulator. It can open circuit in DC circuit and is one of the most commonly used electronic components in SMT processing industry.
Chip capacitors are mainly divided into NPO capacitors, X7R capacitors, Z5U capacitors and Y5V capacitors. The difference between them is mainly due to the different filled media. With the same volume, the capacity of capacitors formed by different filled media is different, and the resulting dielectric loss and capacity stability of capacitors are also different. Therefore, when using capacitors, different capacitors should be selected according to their different functions in the circuit.
1、 NPO capacitor
NPO is one of the most commonly used monolithic ceramic capacitors with temperature compensation characteristics. Its filling medium is composed of rubidium, samarium and some other rare oxides.
Chip capacitor
NPO capacitor is one of the most stable capacitors in capacitance and dielectric loss. When the temperature is from - 55 ℃ to 125 ℃, the change of capacitance is 0 ± 30ppm/℃, and the change of capacitance with frequency is less than ± 0.3 Δ C。 The drift or hysteresis of the NPO capacitor is less than ± 0.05%, which is negligible compared with the film capacitor larger than ± 2%. The change of its typical capacity relative to service life is less than ± 0.1%. The capacitance and dielectric loss of NPO capacitors vary with the frequency depending on the packaging form. The frequency characteristics of large package size are better than those of SMAll package size. The following table shows the available capacity ranges of NPO capacitors.
Encapsulated DC=50V DC=100V
0805 0.5---1000pF 0.5---820pF
1206 0.5---1200pF 0.5---1800pF
1210 560---5600pF 560---2700pF
2225 1000pF---0.033 μ F 1000pF---0.018 μ F
NPO capacitors are suitable for slot capacitors of oscillators, resonators, and coupling capacitors in high-frequency circuits.
2、 X7R capacitor
X7R capacitors are called temperature stable ceramic capacitors. When the temperature is between - 55 ℃ and 125 ℃, the capacity change is 15%. It should be noted that the capacitor capacity change is nonlinear at this time.
Chip capacitor
The capacity of X7R capacitor is different under different voltage and frequency conditions, and it also changes with time, about 1% every 10 years Δ C. It shows that it has changed by about 5% in 10 years.
X7R capacitor is mainly used in industrial applications with low requirements, and its capacity change is acceptable when the voltage changes. Its main feature is that the electric capacity can be relatively large under the same volume. The following table shows the available capacity range of X7R capacitor.
Encapsulated DC=50V DC=100V
0805 330pF---0.056 μ F 330pF---0.012 μ F
1206 1000pF---0.15 μ F 1000pF---0.047 μ F
1210 1000pF---0.22 μ F 1000pF---0.1 μ F
2225 0.01 μ F---1 μ F 0.01 μ F---0.56 μ F
3、 Z5U capacitor
Z5U capacitor is called "universal" ceramic monolithic capacitor. The first thing to consider here is the temperature range. For Z5U capacitor, its small size and low cost are the main factors. For the above three ceramic monolithic capacitors, Z5U capacitor has the largest capacitance under the same volume. However, its capacitance is greatly affected by the environment and working conditions, and its aging rate can drop by 5% every 10 years at most.
Chip capacitor
Although its capacity is unstable, it has a wide range of applications due to its small size, low frequency response of equivalent series inductance (ESL) and equivalent series resistance (ESR). Especially in the application of decoupling circuit. The following table shows the value range of Z5U capacitor.
Encapsulation DC=25V DC=50V
0805 0.01 μ F---0.12 μ F 0.01 μ F---0.1 μ F
1206 0.01 μ F---0.33 μ F 0.01 μ F---0.27 μ F
1210 0.01 μ F---0.68 μ F 0.01 μ F---0.47 μ F
2225 0.01 μ F---1 μ F 0.01 μ F---1 μ F
Other technical indexes of Z5U capacitor are as follows:
Operating temperature range 10 ℃ - 85 ℃
Temperature characteristic 22% ------ 56%
Maximum dielectric loss 4%
4、 Y5V capacitor
Y5V capacitor is a kind of universal capacitor with a certain temperature limit. Its capacity can vary from 22% to - 82% in the range of - 30 ℃ to 85 ℃. The high dielectric constant of Y5V allows up to 4.7 μ F Capacitor.
Chip capacitor
The value range of Y5V capacitor is as follows
Encapsulation DC=25V DC=50V
0805 0.01 μ F---0.39 μ F 0.01 μ F---0.1 μ F
1206 0.01 μ F---1 μ F 0.01 μ F---0.33 μ F
1210 0.1 μ F---1.5 μ F 0.01 μ F---0.47 μ F
2225 0.68 μ F---2.2 μ F 0.68 μ F---1.5 μ F
Other technical indexes of Y5V capacitor are as follows:
Operating temperature range - 30 ℃ - 85 ℃
Temperature characteristic 22% ------ 82%
Maximum dielectric loss 5%
When selecting the chip capacitor, we should not only see the quality and price, but also see which type the chip capacitor belongs to. Different capacitors should be selected according to the different roles of capacitors in the circuit to achieve the highest value of the chip capacitor.
The Circuit board manufacturer and circuit board designer will explain the four classifications and characteristics of chip capacitors.