Multilayer Ceramic Capacitor (MLCC) is one of the main passive chip components in electronic equipment
It was born in the 1960s, to this day, it still maintains its advantages in the global MLCC field, mainly manifested in the production of MLCC with characteristics such as high reliability, high precision, high integration, high frequency, intelligence, low power consumption, large capacity, miniaturization, and low cost.
Multilayer Ceramic Capacitor (MLCC), abbreviated as chip capacitor, is a ceramic dielectric film with printed electrodes (inner electrodes) that is stacked in a staggered manner. After one-time high-temperature sintering, a ceramic chip is formed, and then a metal layer (outer electrode) is sealed, Multilayer Ceramic Capacitor (MLCC) is also called monolithic ceramic capacitor
MLCC not only has the characteristic of "direct and direct connection" of capacitors, but also has the characteristics of small volume, large specific capacitance, long service life, high reliability, and suitable for surface installation. With the rapid development of the world electronics industry, as the fundamental component of the electronics industry, chip capacitors are also developing at an astonishing speed, increasing by 10% to 15% annually
With the improvement of reliability and integration of chip capacity products, their scope of use is becoming wider and wider, and they are widely used in various military and civilian electronic machines and equipment. Such as computers, telephones, program-controlled switches, precision testing instruments, radar communication, etc.
Structure of Multilayer ceramic capacitor mlcc
The structure of ceramic capacitors is generally composed of Ag or AgPd as the internal electrode conductor, BaTiO3 as the ceramic medium, and multi-layer ceramic structures are formed by high-temperature sintering. The device end coating (outer electrode) is generally sintered Ag/AgPd, followed by a layer of Ni barrier layer (to block the internal Ag/AgPd material and prevent it from reacting with external Sn), and then Sn or SnPb layers are prepared on the Ni layer for welding. In recent years, there have also been MLCC products using Cu at the termination
Classification of Multilayer ceramic capacitors mlcc
Ceramic capacitors mlcc can be mainly divided into two types based on their dielectric types, namely Class I ceramic capacitors and Class II ceramic capacitors.
Class I ceramic capacitor, formerly known as high-frequency ceramic capacitor, refers to a capacitor made of ceramic dielectric with low dielectric loss, high insulation resistance, and a linear change in dielectric constant with temperature. It is particularly suitable for resonant circuits and other circuits that require low losses and stable capacitance, or for temperature compensation.
Class II ceramic capacitors, formerly known as low frequency ceramic capacitors, refer to capacitors that use ferroelectric ceramics as their dielectric, hence also known as ferroelectric ceramic capacitors. This type of capacitor is larger than capacitance, and its capacitance varies nonlinearly with temperature, resulting in larger losses. It is often used in electronic devices for bypass, coupling, or other circuits with low requirements for loss and capacitance stability.
Class I Multilayer ceramic capacitors mlcc
Class I ceramic capacitors mlcc such as: NP0 and C0G are extremely stable media with extremely low temperature coefficient and no aging phenomenon. The loss factor is not affected by voltage, frequency, temperature, and time. The dielectric coefficient can reach 400, and the dielectric strength is relatively high. This medium is very suitable for high-frequency (especially high-frequency power capacitors for industrial high-frequency induction heating, high-frequency wireless transmission and other applications), ultra-high frequency, and working environments with strict requirements for capacitance and stability, such as timing and oscillation circuits. The only drawback of this type of dielectric container is that the capacitance cannot be large (due to the relatively small dielectric coefficient), Usually, the capacitance of 1206 surface mounted C0G dielectric capacitors ranges from 0.5PF to 0.01μF.
Class II Multilayer ceramic capacitors mlcc
Class II stable ceramic dielectric materials, such as standard X7R and X5R, have a significant variation in dielectric coefficient with temperature and are not suitable for occasions with high temperature coefficient requirements such as timing and oscillation. However, due to their large dielectric coefficient (up to 1200), their capacitance can be relatively large, making them suitable for coupling, bypass, and filtering with high temperature requirements for working environments (X7R: -55~+125 ℃). Typically, the capacitance of the 1206 SMD package can reach 10 μF or higher;
Class II usable ceramic dielectric materials, such as Z5U and Y5V, have a significant variation in dielectric coefficient with temperature and are not suitable for occasions with high temperature coefficient requirements such as timing and oscillation. However, due to their large dielectric coefficient (up to 1000-12000), their capacitance can be increased, making them suitable for coupling, bypass, and filtering in general working environment temperature requirements (-25~+85 ℃). Usually, 1206 surface mounted Z5U and Y5V dielectric capacitors can even reach a capacity of 100μF. In a sense, it is a strong competitor to replace tantalum electrolytic capacitors.
What is the temperature coefficient of C0G?
C: indicates that the effective number of the capacitance temperature coefficient is 0 ppm/℃
0: means that the multiplier of a significant number is -1 (i.e. 10 to the power of 0).
G: indicates a tolerance of ±30ppm with temperature
Is NP0 and C0G the same capacitor?
NP0 is the abbreviation for Negative Positive Zero, used to represent the temperature characteristics of. This indicates that NP0 has excellent capacitance temperature characteristics and does not exhibit capacitance drift with changes in positive and negative temperatures.
As we have already known, C0G is the most temperature stable type of Class I ceramics, with a temperature characteristic of approximately 0, satisfying the meaning of "negative positive zero". So C0G is actually the same as NP0, just two standard representations (of course, C0K, C0J, etc. with smaller capacitance and slightly lower accuracy are also NP0 capacitors).
NP0 capacitors have different characteristics of capacitance and dielectric loss with frequency variation depending on the packaging form. Large packaging sizes have better frequency characteristics than small packaging sizes.
Performance of Multilayer ceramic capacitors MLCC
(1) Capacity and tolerance: The maximum allowable deviation range between actual capacitance and nominal capacitance. The commonly used capacity tolerance are: J level ± 5%, K level ± 10%, and M level ± 20%. The allowable tolerance of precision capacitors is relatively small, while the tolerance of electrolytic capacitors is relatively large, and they adopt different tolerance levels. The accuracy level of commonly used capacitors is the same as the representation method of resistors. Expressed in letters: Level D - ± 0.5%; Level F - ± 1%; Grade G - ± 2%; Grade J - ± 5%; K-level - ± 10%; M-level - ± 20%
(2) Rated working voltage: The maximum DC voltage that a capacitor can withstand in a circuit for long-term stability and reliability, also known as withstand voltage. For devices with the same structure, medium, and capacity, the higher the withstand voltage, the larger the volume.
（3) Temperature coefficient: The relative change in capacitance for every 1 ℃ change in temperature within a certain temperature range. The smaller the temperature coefficient, the better.
（4）Insulation resistance (IR): Used to indicate the magnitude of leakage. Generally, small capacity capacitors have high insulation resistance, ranging from a few hundred megaohms to a few thousand megaohms. The insulation resistance of electrolytic capacitors is generally small. Relatively speaking, the higher the insulation resistance, the better, and the smaller the leakage. General C0G class>1000ΩF, X7R and Y5V class>500ΩF
（5）Loss (DF): The energy consumed by a capacitor during unit time heating under the action of an electric field. These losses mainly come from dielectric losses and metal losses. Usually represented by the tangent of the loss angle. The most standard writing method for loss is to use the percentage writing method, for example: COG <0.015%; X7R＜2.5%; Y5V<3.5%,
generally COG <10 * 10-4; X7R <250 * 10-4; Y5V<500 * 10-4.
（6）Frequency characteristic: The property of a capacitor's electrical parameters changing with the frequency of the electric field. Capacitors operating at high frequencies have a corresponding decrease in capacitance due to their lower dielectric constant at high frequencies compared to low frequencies. The loss also increases with increasing frequency. In addition, during high-frequency operation, the distribution parameters of capacitors, such as electrode resistance, resistance between leads and electrodes, electrode inductance, and lead inductance, can all affect the performance of capacitors. All of this limits the frequency of capacitor use.
Different types of capacitors have different maximum usage frequencies. Small mica capacitors within 250MHZ; The circular ceramic dielectric capacitor is 300MHZ; The circular tube type ceramic dielectric capacitor is 200MHZ; Disk shaped ceramic dielectric can reach 3000MHZ; 80MHZ for small paper capacitors; Medium paper capacitors only have 8MHZ.
Multilayer Ceramic capacitors MLCC failure causes
The failure causes of multilayer ceramic capacitors can be divided into external factors and internal factors.
a） internal factor
1.Void in ceramic medium
The main factors leading to the formation of voids are organic or inorganic pollution in the ceramic powder, improper control of the sintering process, etc. The generation of voids can easily lead to leakage, which in turn leads to local heating inside the device, further reducing the insulation performance of the ceramic medium and leading to an increase in leakage. This process occurs cyclically and deteriorates continuously, leading to serious consequences such as cracking, explosion, and even combustion of multi-layer ceramic capacitors.
The sintering of multilayer ceramic capacitors (MLCC) involves stacking and co firing of multiple layers of materials. The sintering temperature can reach over 1000 ℃. The weak interlayer bonding force, the volatilization of internal pollutants during the sintering process, and improper sintering process control can all lead to delamination. The hazards of delamination, voids, and cracks are similar, and they are important inherent defects in multi-layer ceramic capacitors.
b） External factors
1.Thermal Crack
The main reason is that the device is subjected to temperature shock during welding, especially wave soldering, and improper repair is also an important reason for temperature shock cracks.
The characteristic of multi-layer ceramic capacitors is that they can withstand large compressive stresses, but their resistance to bending is relatively poor. Any operation that may cause bending deformation during device assembly may lead to device cracking. Common stress sources include: chip alignment, circuit board operation during the process; Factors such as people, equipment, and gravity during the circulation process; Insertion of through-hole components; Circuit testing and board segmentation; Circuit board installation; Circuit board positioning riveting; Screw installation, etc. This type of crack generally originates from the upper and lower metallized ends of the device and extends towards the interior of the device at an angle of 45 ℃. This type of defect is also the type of defect that actually occurs the most.
Multilayer Ceramic capacitors MLCC of UF Capacitors
UF Capacitors is a well-known and respected capacitors manufacturer and factory based in China, with a history dating back to 1995. We have earned the prestigious ISO9001 certification, reflecting our commitment to quality and excellence in the production of electronic components.
Most of our team members hold graduate degrees. In our industry, we are at the forefront in both technology and management.
In summary, the MLCCs we produce are designed and manufactured to be on par with top brands like Murata and TDK, exhibiting excellent quality without any compromise.
At UF Capacitors, we take pride in our commitment to delivering top-quality ceramic capacitors that meet the diverse needs of our global clientele.
Whether it's a high-voltage MLCC or a compact disc ceramic capacitor, our capacitors are designed to exceed your expectations.
Partner with us for reliable, high-performance electronic components that power innovation and drive progress in various industries.
Here are some cross reference from UF Capacitors
|
P/N of UF Capacitors |
Description of UF Capacitors |
P/N of Competitor |
|
0805B105K100CR |
1uF 10V X7R +/-10% 0805 T&R RoHS |
C0805C105K8RACTU |
|
0805B106K100CR |
10uF 10V X7R +/-10% 0805 T&R RoHS |
0805ZC106KAT2A |
|
0603B273K160CR |
0.027uF 16V X7R +/-10% 0603 T&R RoHS |
C0603C273K4RACTU |
|
1210X225M101CR |
2.2uF 100V X5R +/-20% 1210 T&R RoHS |
HMK325BJ225MM-P |
|
1206N221J500CR |
220pF 50V NPO +/5% 1206 T&R RoHS |
12065A221JAT2A |
|
1812B102K102CR |
1000pF 4KV X7R +/-10% 1812 T&R RoHS |
HV1812Y102KXVATHV |
|
0402X225K100CR |
2.2uF 10V X5R +/-10% 0402 T&R RoHS |
C1005X5R1A225K050BC |
|
0603X474K100CR |
0.47uF 10V X5R +/-10% 0603 T&R RoHS |
CC0201KRX5R6BB474 |
|
1210X107M160CR |
100uF 16V X5R +/-20% 1210 T&R RoHS |
CC1210MKX5R7BB107 |
|
0201X105M100CR |
1uF 10V X5R +/-20% 0201 T&R RoHS |
CM03X5R105M10AH |
|
0402X106M100CR |
10uF 10V X5R +/- 20% 0402 T&R RoHS |
0402X106M100CT |
|
0603B102K101CR |
1000pF 100V X7R +/-10% 0603 T&R RoHS |
C0603C102K1RACTU |
How to Obtain a Quote from UF Capacitors?
You can easily send an email to lily@ufcapacitors.com, the engineering and sales team in UF Capacitors will help you select the correct polymer aluminum capacitors.
For more details, pls visit our website: www.ufcapacitors.com