Hi team,
Could you please advise how to derive equation (9) in the datasheet 27 page for
calculating Output capacitor considering load step?
regards,
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Hi team,
Could you please advise how to derive equation (9) in the datasheet 27 page for
calculating Output capacitor considering load step?
regards,
Hi Shinji,
I'm not particularly familiar with this equation, but basically it is a function of the crossover frequency that will give the maximum phase boost, the gain of the error amplifier & feedback network at that particular crossover frequency, and some relation between the pole of the inductor and output load. In general it is quite complicated, and it may be better to dive into some literature.
If you just want a quick and practical way to estimate a value, equation 12 should work.
Thanks,
Richard
Hi Richard-san,
equation (12) in the apps note seems minimum capacitance to meet certain ripple voltage.
The equation (9) in the datasheet is the minimum capacitance at load step condition.
Is there a equation to calculate load step condition?
regards,
Hi Shinji,
Load-step is usually selected or specified in the design.
Usually you can start with 50% of the maximum output current.
Thanks,
Richard