Suppression for the output ripple and noise / Selection of output filter capacitance| Ahhesionpower.com
Suppression for the output ripple and noise / Selection of output filter capacitance In general applications, the output end does not need the external capacitance, and the DC-DC Converters can work well, but in some applications that are more sensitive to ripple, the additional filter capacitance is needed. The frequency of the ripple (f) depends on the switching frequency of the DC-DC Converters . Reducing the ripple can be solved by increasing the value of filter capacitance. According to the switch frequency, the capacitance of different materials can be used. If the frequency is less than 100KHz, the high frequency aluminum capacitance or tantalum capacitance can be used; the frequency range of 100kHz-500kHz can be used by tantalum capacitance or polymer capacitance ; the frequency range of 200kHz-5MHz can use large-capacity multi-layer stone (X7R or X5R) to filter noise peaks. The output should not be increased with a large electrolytic capacitance. Due to...