The so-called capacitance is the electronic components that contain and release the charge. The basic principle of capacitance is charge discharge, and of course rectification, oscillation and other functions. In addition, the structure of the capacitor is very simple, mainly composed of two positive and negative electrodes and insulating medium sandwiched in the middle, so the type of capacitance is mainly determined by the electrode and the insulating medium. There are many uses of capacitors.
The 1. way is DC: the function is to prevent DC passing and let the communication go through.
2. bypass (decoupling): provides a low impedance path for some parallel components in the AC circuit.
3. coupling: as a connection between two circuits, it allows AC signals to pass through and transmit to the next level.
4. filtering: This is very important for DIY. The capacitance on the graphics card is basically the same.
5. temperature compensation: compensate for other components' inadaptability to temperature, and improve the stability of the circuit.
6. timing: capacitor and resistor are used together to determine the time constant of the circuit.
7. tuning: tuning the frequency dependent circuits, such as mobile phones, radio and TV sets.
8. rectifier: open or close half closed conductor switch element at a predetermined time.
9., energy storage: storage of electric energy for release when necessary. For example, camera flash, heating equipment and so on. Nowadays, the energy storage level of some capacitors is close to the level of lithium battery. The energy stored by a capacitor can be used by a cell phone for a day.