FLY BACK OUTPUT CAPACITOR SELECTION CRITERIA

Hi Vivek,

Thank you for your interests. The 6kHz is the loop bandwidth (see Figure 7 of the document), and the step load response should recover in about 1/6kHz time window. and before it is recovered the output capacitor should supply the additional current of the step. By satisfying (21) the output capacitor will maintain the output voltage from dipping below 200mV.

Thanks,
Youhao Xi, Applications Engineering

Thanks for the reply

I have two qurestions

But i dont have Loop Small Signal Response graph, then how to decide Fbw.

1) From below figure marked area is correct?

2) In general how to take Fbw value any formula or thumb rule?

i need little more clarity , how to arrive fbw value consider the situation designer dont have loop signal response graph