The capacitor can be used to reduce the ripple and absorb noise generated by the switching regulator, stabilize the background voltage and improve the stability and transient response ability of the equipment. There shall be no ripple noise or residual jitter when outputting power. Tantalum capacitors are usually used to reduce the ripple of these circuits, but tantalum capacitors may be affected by the noise of switching regulators, resulting in unsafe transient phenomena.
Bare board power supply is used to control these power supplies. Due to the significant advantages of bare board power supply, bare board power supply has become the standard power supply of most electronic products. The capacitor can be used to reduce the ripple and absorb noise generated by the switching regulator. It can also be used to stabilize the background voltage and improve the stability and transient response ability of the equipment. The output power shall be free from ripple noise or residual jitter. Tantalum capacitors are often used to reduce the ripple of these circuits, but tantalum capacitors may be affected by the noise of switching regulators, resulting in unsafe transient phenomena.
How to select the capacitor voltage of bare board power supply? The most important applications of capacitors in power supply are energy storage, surge voltage protection, electromagnetic interference suppression and control circuit. We can understand the competitive or complementary relationship between these dielectric technologies in different application fields.
How to select the capacitor voltage of the bare board power supply, the energy storage capacitor collects the charge through the rectifier, and transmits the stored energy to the output of the power supply through the converter lead. The rated voltage is 40 ~ 450 VDC and the capacitance is 220 ≤ 150000 μ F aluminum electrolytic capacitor. According to different power requirements, the device sometimes adopts the form of series, parallel or combination. For the power supply with power level more than 10 kW, the storage tank spiral terminal capacitor with large volume is usually used. How to select the capacitance voltage of bare board power supply? In order to select the appropriate capacitance value, its rated DC voltage, allowable voltage pulsation and charge discharge cycle must be checked. However, the following parameters should be considered when selecting the applicable electrolytic capacitor. The capacitive ripple current in a typical power supply is the combination of waveform currents of various frequencies. The root mean square (RMS) value of the wave current determines the temperature rise of the capacitor.
A common mistake in selecting the capacitor voltage of bare board power supply is to calculate the RMS current load by increasing the square value of wave current at each frequency. In fact, it must be considered that the ESR of the capacitor decreases with the increase of the mature frequency. The correct method is to estimate the wave current of high frequency (to 100Hz) according to the frequency diagram of wave factor. The estimated square value of the current is used to determine the wave current. This is the real current load. Since the ambient temperature determines the life of the capacitor under load conditions, the famous manufacturers have accurately defined the relationship between the wavy current load, ambient temperature and the probability life. Under actual working conditions, the probability life is determined by pulsating current load and ambient temperature, and the published probability life is taken as the absolute value.
