Capacitor function

Bypass

The bypass capacitor is an energy storage device that supplies energy to the local device, which equalizes the output of the regulator and reduces the load requirements. Like a small rechargeable battery, the bypass capacitor can be charged and discharged to the device. To minimize impedance, the bypass capacitor should be as close as possible to the power supply and ground pins of the load device. This can well prevent ground potential elevation and noise caused by excessive input values. The ground bounce is the voltage drop when the ground connection is passed through a large current glitch.

Filter

Theoretically (that is, assuming the capacitor is a pure capacitor), the larger the capacitance, the smaller the impedance and the higher the frequency of passing. However, in fact, the capacitance of more than 1μF is mostly an electrolytic capacitor, which has a large inductance component, so the impedance will increase after the frequency is high. Sometimes you will see a small capacitor with a larger capacitance and a small capacitor. At this time, the large capacitor passes through the low frequency and the small capacitor passes through the high frequency. The function of the capacitor is to pass the high impedance and low frequency. The larger the capacitance, the easier the low frequency passes, and the higher the capacitance, the easier it is to pass. Specifically used in filtering, large capacitor (1000μF) filter low frequency, small capacitor (20pF) filter high frequency.

Energy storage

The energy storage capacitor collects charge through the rectifier and transfers the stored energy through the converter lead to the output of the power supply. Aluminum electrolytic capacitors (such as EPCOS B43504 or B43505) with a voltage rating of 40 to 450 VDC and a capacitance between 220 and 150 000 μF are more commonly used. Depending on the power requirements, the devices are sometimes used in series, in parallel, or a combination thereof. For power supplies with power levels greater than 10 kW, bulky screw-type terminal capacitors are typically used.

If you want to know more, our website has a product specification for capacitor, you can go to ALLICDATA ELECTRONICS LIMITED to get more information