How to select capacitance quickly in switching power supply(II)

3, capacitor selections in switching power supply need to know the characteristic of capacitance itself.

In switching power supply design, the highest frequency capacitance is ceramic capacitor electrolytic capacitor and tantalum capacitor. It needs to understand their characteristic differences to select quickly.

Ceramic capacitor capacitance value is smaller high frequency characteristic good working temperature range wide ESR than electrolytic capacitor small volume no polarity;

Electrolytic capacitance can be large but the range of working temperature is narrow ESR is larger and polarity is relatively large;

Tantalum capacitor ESR is smallest, capacitance value is larger than ceramic capacitor, polarity, safety regulation performance is poor, easy fire.

Understanding the characteristics of these capacitors can be done easily when using them.

4, capacitance selections in switching power supply and understanding of usage environment.

The environment of capacitor is divided into circuit interior environment and circuit exterior environment. Circuit interior environment includes frequency voltage value current value capacitance in circuit main function etc.

According to circuit frequency, capacitance types can be determined;

According to voltage value, voltage value can be determined;

The main function of the circuit can be used to reference capacitance value of capacitor type etc.

According to the external environment of circuit selection capacitor selection product working environment temperature safety regulation requirements etc. can be used to reduce capacitor selection range.