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I need to use a supercapacitor to power a circuit for short pulses evenly. So with the same current out every pulse. To do this, I thought to use a boost converter to get a constant current out every pulse, just using Ohm's law, but when I tried this the output current got lower and lower every pulse. This to me doesn't really make sense, but boost converters to me are a mystery, so I thought maybe I could get some answers? If this is the case, that I cant get constant current out, I was thinking of fixing this with some capacitors that I then unload instead. Could anybody explain this phenomenon?

Edit: Sorry for the lack of information!. Ok, I'd need a constant current source, but wouldn't I be able to charge capacitors to a certain voltage to get a similar "burst" of current every time then? It was wrong to describe the current as "constant", more that the current pulse (by my estimations about 12uS) needs to be similar every time. What I was testing was the circuit added below. I was thinking of powering a coil for something similar to a coilgun: circuit without capacitors

But since that circuit is based on logic that doesn't work (it does seem to go against conservation of energy), maybe charging up capacitors to a certain voltage inbetween would work? Something similar to this: circuit with capacitors

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    \$\begingroup\$ You'll have to show us details. Your question makes little sense as stated. "Ohm's law" and "boost converter" don't really go together. \$\endgroup\$
    – John Doty
    Commented Jan 25 at 14:33
  • \$\begingroup\$ I would use Cap-Bank ->Buck/Boost DC/DC -> Decoupling for transients -> Pulse switching. To charge the caps extra circuits are required ofc. \$\endgroup\$
    – ElectronicsStudent
    Commented Jan 25 at 14:40
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    \$\begingroup\$ As mentioned by John Doty this question doesn't really make sense. I think you mean that you want a short pulse of a defined current out of a super capacitor. A super cap drops voltage as it is discharged, so you need your constant current source to compensate for this. You haven't told what your super capactor is, anything your boost converter, what load you're powering, what current you want to produce or how long for. A schematic of what you've got would probably help us understand what you're trying to ask as well. Without this information you risk your question being closed. \$\endgroup\$
    – Puffafish
    Commented Jan 25 at 15:23
  • \$\begingroup\$ Capacitors by law don't work this way. Batteries don't work this way, there is always a voltage drop when you draw current from any non-ideal device. If you want constant current, then you'll need a constant current regulator. \$\endgroup\$
    – Voltage Spike ♦
    Commented Jan 25 at 16:14
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    \$\begingroup\$ To make a narrow constant current pulse into an inductor, you need a narrower very high voltage pulse to get the current going, and another to stop it. What are you trying to do here? \$\endgroup\$
    – John Doty
    Commented Jan 25 at 21:17

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