MOS Power IC Full Range

Filter 18.432M

As the "heart" of a satellite, the reliability of the power supply plays a critical role. The DC/DC module within the satellite's power system primarily serves to convert the 42V DC output voltage into various other DC voltage levels to cater to the power needs of diverse onboard devices. The input filter of the DC/DC module has two primary functions: first, it prevents electromagnetic interference generated by the module from propagating through the power lines and affecting other equipment; second, it ensures that high-frequency voltages on the power line do not pass through to the output of the DC/DC module. An LC passive filter fulfills these functions effectively. This design aims to achieve a balance between the size and cost of the filter.

Undamped LC Filter Figure 1 illustrates an undamped LC passive filter. Ideally, a second-order filter exhibits a 12 dB attenuation per octave beyond the resonant frequency \(f_0\). Before \(f_0\), there is no gain, and the gain peaks at \(f_0\).

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