I have a feeling auto-correct was also trying to help...
Spectacularly stupid software fails are all around us every day, and people are still eager to believe that, any minute now, software will drive cars more safely than humans can.
-Gnobuddy
I guess not, as the recharge current is then only limited by the caps DCR which i suppose to be lower then the power stage impedance/resistance of the amp.
Beside this, your writing-style appears very rough and unfriendly to me, not only in this thread.
What's the problem about this sentence construction? "If you only have.." is proper english, is it not?
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This deduction is a complete mess. DCR is an unsuitable term here. I guess you ment ESR, since it is a low value, while DCR would be a very high value. But even if you compare ESR to resistance of the amplier it doesn't give any information about the current, since the voltage on ESR is very much lower but unknown.
A correct way of thinking must involve a discharging time (lets call it Td) and then a recharging time (Tr). During Td the voltage is decreasing, during Tr voltage is increasing. Ipsu=Iload+Icap. The voltage level during charging and discharging is basically the same, just with reversed order in time. Since charging current of the capacitor is negative during Td (Icap=C*dV/dt, <0), Iload must be higher than Ipsu. For first approximation lets assume the PSU output characteristics is time-invariant. Then Ipsu is the same during Td and Tr. Conclusion: Ipsu during recharge (or at any time actually) must be lower than the maximal load current.
Now you may ask what if the previous approximation is not true. There are theoretically 2 options. 1st: The current limit is decreasing with time. This is very typical. In this case the recharging current is even more lower. 2nd: the current limit is increasing with time. This is a behaviour that no SMPS shows. It is hard to implement and harmful, so you can easily get rid of the idea having such an intentionally ruined design.
Please note:
I did not guess when I suggested trying a big cap. I analized and successfully implemented such arrangements many times. Denying this based on ignorance and making obviously false statements against it hurts me.
Can be proper English syntactically. The problem is about the meaning (semantics). The world "only" indicates a restriction for the following subject. "Only one" means no more than 1. "Only with a spoon" means without knife, fork, stick etc... but what could "Only have" mean? What is the restriction? To be more precise: what would be the denial of it? It's impossible for me to imagine any meaning for it that doesn't create an other problem in the context.
Yes, and in this case recharge current was higher than load current. But this case is completely unreal. There are at least 2 serious mistake in the premises, but unfortunately Im not sure what you mean duty cycle, therefore before correcting mistakes I would have to know what do you mean exactly. Duty cycle can refer to the internal switching operation of the SMPS, but this is not something you can observe outside, switching freq stays inside, and you can see only the average current.
You may also refer to the varying nature of the load (music signal controlled) by this duty cycle term, but then the way it work is completely twisted: discharging lasts to 0.1, charging lasts as long as it needed, and the rest of the time no or very low current flows. The situation you described could happen only if the PSU was controlled by the music, but it is definitely not the case here.
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