General selection of materials for capacitors

A capacitor is a basic component of an electronic system and is a basic unit of a circuit that can perform a predetermined function and can no longer be divided. Due to the large number and variety of capacitors, their performance, reliability and other parameters have a great impact on the technical performance, reliability, life cycle and other technical indicators of the entire electronic product.

The general selection of materials for capacitors is as follows:

1. The selected device follows the company's normalization principle and selects the type of material as little as possible without affecting the function and reliability.

2. The material with the "preferred grade" of "A" in the material code library is preferred.

3. The preferred life cycle is a growing, mature device.

4. Select the special batch process for the device that was born and dropped.

5. Carefully select devices whose life cycle is in decline. It is forbidden to use discontinued devices.

6. The power device is preferably a package type with a smaller RjA thermal resistance and a larger Tj junction temperature.

7. It is forbidden to select devices with package size less than 0402 (inclusive).

8. Anti-ESD capability is at least 100V, and it is required to design anti-static measures.

9. The selected component MSL (moisture sensitivity level) cannot be greater than 5 (inclusive).

10. The model of sealed vacuum packaging is preferred. If the MSL (moisture sensitivity level) is greater than grade 2 (inclusive), it must be sealed with vacuum.

11. The model of tape and packaging and tray packaging is preferred. In the case of devices with a moisture sensitivity level of 2 or higher, a disc-shaped plastic braided package is required, and the disc-shaped plastic braid must be able to withstand a high temperature of 125 °C.

12. For key components, at least two brands of models can be substituted for each other, and some should also consider solution-level replacement.

13. The materials used are required to meet the requirements of antistatic, flame retardant, anti-corrosive, anti-oxidation and safety regulations.