Q: What if I have more than two outputs?
A: Just extrapolate, using the two output case as a guide!

Suppose you have a third output with N4 turns and Output Capacitor C11. Then add (N4/N2)squared times C11 to C4 plus (N3/N2)squared times C5.

Likewise, if the additional output inductor is L4, you would parallel (N2/N4)squared L4 with L2 || (N2/N3)squared L3.

Q: This all seems like a lot of capacitors!
A: Remember that your Energy Transfer Caps and Output Caps will be film, monolithic, or ceramic surface mount, with values <100uF. Even the Damping Caps will be <1000uF, and you don't have to worry about esr & esl since they do not handle switched currents!
The caps on the (high voltage) input side are even smaller in value which makes up for their being higher voltage parts.

Q: Why do most designs using other converters feature huge banks of electrolytic caps?
A: The multiple oversize capacitors are necessary to bring down the impedance of the whole bunch. Electrolytics are not much good for switched waveforms, since they are inductive in impedence at the switching frequency and its harmonics. They usually cease to be capacitive before 10KHz.

By the time you reach fs, they are acting as very small DC blocked inductors. This often produces a significant square wave voltage ripple at the output, which is caused by the voltage square wave from the switch being divided between the large output inductor and the esl of the output caps.

In addition to great size and weight, these store considerable amounts of energy, and will dump into a load short, often starting a fire and ruining the load board. The current limit is unable to stop this, since such output caps are fully charged to Vout.

Calculate the stored energy of your output electrolytics via (1/2)LIsquared sometime, and convert to Joules of energy. You will find it's something like dropping a heavy book onto your desk from over a foot up! Quite a thump, and even something of a safety hazard.

Q: Would these other converters benefit from the damping technique suggested here?
A:  Yes, shunt damping, as it is called, works well with all switching converters. This was shown in Dr. R.D. Middlebrook's papers re damping and the Canonical Model.

But, the topological shortcomings of the other converters are still there, as discussed at length further on in this site!

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