RMS Current Through the Output

Figure 12-14 The RMS Current Through the Output Capacitor of a Buck...

All the basic design equations we can write for the RMS, dc, ac, or peak currents in the input/output capacitors and the switch, when operating in conventional CCM, apply to the converter in FCCM too (though there may be some additional losses, as for example when the current flows through the body diode of the top mosfet). This, despite the fact that r can now exceed 2. In other words, the CCM equations do not get invalidated in FCCM. 

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