The role of chip capacitors:? In the DC circuit, a capacitor is the equivalent of disconnection. A capacitor is a device capable of storing electric charge, is one of the most commonly used electronic components. It must start with the structure of the capacitor. The simplest is by the capacitor plates and the intermediate ends of the insulating dielectric (including air) configuration. After energization, the charged plate, forming a voltage (potential difference), but since the intermediate insulating material, so the entire capacitor is not electrically conductive. However, this situation is not exceeded in the threshold voltage of the capacitor (breakdown voltage) of preconditions. We know that any substances are relatively insulated, to increase when the voltage across the substance to a certain extent, the material can be electrically conductive, we call this voltage is called the breakdown voltage. Capacitance is no exception, after the capacitor is the breakdown, it is not an insulator of. However, at the secondary level, this voltage is not seen in the circuit, so are operating below the breakdown voltage, can be used as an insulator to see. Ceramic capacitor? However, in AC circuits, because the direction of the current over time as a function of certain changes. The process of charging and discharging the capacitor is a time, and this time, the changing electric field between the plates is formed, and this is also a time-varying electric field is a function. In fact, the current through the field in the form of a capacitor between adopted. At the secondary level, there is a saying, called through exchanges, DC resistance, that is the capacitance of this nature. Multilayer ceramic chip capacitors advantages and features: 1. Can be used to make a small, powerful product. 2. Help to improve production efficiency, automated production. 3. The use of precious metals production, high stability, high temperature, high reliability and long life. 4. You can replace the CBB, aluminum electrolytic, so that miniaturization of electronic products, save space. Products more attractive and better performance. 5. Small ESR ceramic capacitors can be used in some high-frequency circuits, higher efficiency products. Characteristics of high-voltage chip capacitors: the use of thin-layer and multi-layer stack technology SMD ceramic capacitor dielectric layer, so that the capacitance value greatly expand 2. monolithic structure ensure excellent mechanical strength and high reliability 3 accuracy, during automatic assembly due to a high degree of accuracy 4. Just ceramics and metal, so even if no gradual decline phenomenon at a high temperature, low temperature, has a strong reliability and stability 5. Low Distributed capacitance characteristic can be done close to the theoretical value of 6. The circuit design of residual induction coefficient, to ensure a good frequency characteristic 7. The field also received by electrolytic capacitor capacitance, therefore longer life, more built in having high reliability 8. Due to the low power ESR frequency characteristics of a good, it is best suited for high-frequency, high-density high-voltage chip capacitors types of power features:? 1. The equivalent series resistance (ESR) is small, the impedance (Z) is low, with the same tantalum Compared capacitors or electrolytic capacitors, ESR small few times, high energy efficiency, low heat, low prices. 2. Variety, complete specifications, small size. Capacity from 10pF to 47uF, pressure from 10V-6000V, the smallest can reach 1X0.5mm.? 3. polarity, can be used in the presence of very high ripple circuit or AC circuits, and assembly easier. ? 4. stable performance, even if the breakdown would not burn, safe. ? Used in electronic precision instruments. A variety of small electronic devices as resonators, coupling, filtering, bypass. ?? NP0 low capacitance material (10-6800pF): Applicable frequency 1-100MHz 1. Temperature coefficient:? 0 ± 30ppm / ℃, -55 ℃ ~ 125 ℃ ;? 2. capacitance drift: less than ± 0.3% or ± 0.05pF (whichever is greater). ? 3. aging characteristics: no high-capacity capacitors X7R material (6800pF or more): no more than 10KHz 1. applicable frequency temperature characteristics: no more than ± 15%, - 55 ℃ ~ 125 ℃???. ? 2. aging characteristics: 1% ΔC change every 10 years, the performance of 10-year variation of about 5%. Operating temperature is the ambient temperature and the temperature rise of the element and the body. ? Derating design? Designers work in the selection of the capacitor voltage should be considered when applying a DC voltage across the capacitor and the peak AC voltage can not exceed the rated voltage. To ensure the reliability of the line products and recommended derating actual design? Cautions? Operating temperature? Capacitor design category temperature range -55 ℃ ~ 125 ℃, -55 ℃ ~ 85 ℃ two kinds, the designer must ensure compliance with the operating temperature range. To extend the life of the capacitor, recommended operating temperature limits below the upper category temperature 10 ℃ ~ 15 ℃. ? Designers to consider the high voltage capacitor chip capacitors for: lighting power products, high-frequency induction lamp power supply, communication power switch, LED fluorescent constant current drive power, automotive HID lamps (ballast), power modules, medical supply, LED resistance Buck ,, ASDL voice splitter, RJ45 Ethernet interface, digital camera flash, LED Christmas lights, energy saving lamps and a variety of electronic products, mainly used for power supply filtering, power down, voltage, absorb surges protection IC, the basic working principle is to charge and discharge, and of course the rectifier, oscillation and other role. Applied to the power supply circuit, bypass, decoupling, filtering and energy storage MLCC (SMD ceramic capacitor) production process:? 1, the raw material - a key part of the ceramic powder ingredients (raw materials determines the performance of the MLCC) ;? 2 Milling - ;? 3 ingredients by a ball mill (about 2-3 days after the porcelain parts milled ingredients reach micron particle diameter) - a variety of ingredients mixed in a certain proportion; 4, and pulp - additive mixing? Materials and into a paste;? 5, flow along - the mushy paste evenly coated onto the film (film for special materials, ensure the smooth surface) ;? 6, printed electrodes - electrode material printed with certain rules to the stream After the paste-like slurry along (dislocation of the electrode layer in this process to ensure that different size MLCC guaranteed by this process) ;? 7, the laminate - to flow along the slurry was good printing block in accordance with the capacitance value of the electrode Different together, and forming a capacitor body Edition (specific dimensions of the capacitance value is determined by different layers) ;? 8, lamination - the multilayer green body version capable of binding tightly;? 9, cutting - the body body version cut monomer;? 10, ranked glue - the bonding adhesive materials with 390 degrees Celsius to exclude;? 11, roasting - with 1300 degrees Celsius temperature sintered ceramic powder ceramic material is formed into ceramic particles (which lasted a few days, if the temperature control during the firing of bad capacitors prone to embrittlement) ;? 12, chamfered - the rectangular edges worn away, and the electrode exposed, chamfered ceramic particles; 13, capped - the exposed ceramic particles chamfering electrode with copper or silver erected decapitated seal material to form copper (or silver) electrode, and good links adhesive electrodes? ceramic particles to form a capped version (the process determines the capacitor) ;? 14, burning end - will be capped ceramic particles placed inside furnaces copper end (or silver side) electrodes sintered make contact with the electrode version careful; forming First body ceramic capacitors;? 15, nickel-plated - the beginning of the ceramic capacitor body the electrode terminal (silver or copper end side) a thin layer on the electroplated nickel layer, the nickel layer must be completely covered by a copper or silver electrode terminal forming a ceramic Capacitor secondary body (mainly the nickel layer shield electrode and the outermost layer of copper or silver tin interpenetration occurs, resulting in capacitance old bad) ;? 16, tin - the ceramic capacitor body times after nickel plating well on a plated Think of tin layer ceramic capacitors adult (tin is easy to weld materials, tin craft decided capacitance weldability) ;? 17 test - four indicators of the process must be measured: the resistance, voltage, capacitance, DF value of the loss, leakage current Ir and insulation resistance Ri (the process to distinguish between the withstand voltage of the capacitor, the capacitance of the accuracy, etc.)?