In the precise electronic circuit design, CBB capacitors have gradually replaced the traditional polystyrene and cloud -made capacitors due to their volume advantages and performance. However, in some application scenarios, CBB capacitors and security capacitors play a role at the same time. Understanding the differences between the CBB22 capacitance and the security capacitance and their own use methods are very important for circuit designers.
From a performance perspective, the most significant difference between security capacitors and CBB22 capacitors is the outer packaging and electrical structure. Safety capacitors usually use a box structure, which has good flame retardant performance and sealing. Most of the modern CBB22 capacitors use immersion structures to solve sealing problems. In terms of materials, some manufacturers of CBB22 series of capacitors use aluminum film, while some are made of zinc and aluminum film. Zinc and aluminum film products are similar to security capacitors in terms of electrical properties, and have strong DC pressure resistance. The characteristics of aluminum film products are low loss and stronger high -frequency AC pressure resistance, although its DC pressure resistance capacity is slightly inferior to zinc aluminum film.
In terms of usage, due to the relatively low cost, CBB22 can replace security capacitors on many occasions (almost all occasions), provided that it meets the actual DC pressure resistance. For example, in the output power calculation of the semi -bridge circuit, the power of the two 0.47UF CBB22 in DC can approximately consider zero.
The differences in applications are also very obvious. Safety capacitors are mainly used for EMI entry filtering, while CBB capacitors are widely used in circuits such as oscillation, coupling, and blocking volume. Although CBB22 capacitors can replace security capacitors under the conditions of methamphetamine in terms of electrical performance, they have differences in the resistance of voltage resistance. The rated voltage of security capacitors is usually 250/275VAC (level X2), and its DC voltage can reach 2000VDC2S. In contrast, the resistance voltage of the CBB22 capacitor is only 1.6 times the rated voltage.
When choosing, you also need to consider the insulation performance of two kinds of capacitors. CBB22 capacitance uses a polyphonic membrane medium. Due to small loss and low heat, the temperature rise in the use should not exceed the ambient temperature 6 ° C, and the temperature rise of many circuit boards in the actual application is controlled within 4 ° C. If Wen Sheng exceeds this standard, it may indicate that the capacitor's working power is too high. In this case, both capacitors are easy to fail.
In summary, although the security capacitance and CBB22 capacitors are both the type of safety capacitance, there are significant differences in the packaging method, electrical performance structure, cost, use, and selection standards. Understanding these differences is very important for the design of the power filter and the stability of electronic equipment.