7:03 PM
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Can an external defibrillator, used medically to restore normal heart rhythm, deliver a continuous charge? I've been trying to find references to how a defibrillator works, whether it sources with batteries or capacitors, and so on, but the information seems to be evading me.

What is continuous charge? As far as i know, it delivers a relatively short voltage pulse, how is it related to battery or capacitors? Probably there are both in the system...

@JImDearden Unless there's something there I missed, the wiki doesn't answer anything. It mentions that the original defibrillators used capacitor banks, but then goes on to show a simplified diagram of modern defibrillators that use batteries. No dice.
@GregoryKornblum If I wanted to produce a 30-second charge for instance, and were able to get past any software limits restricting that action, is the device itself capable of doing so?

First, it's not charge. It's either voltage or current. Charge- is simply number of electrons. If you want to supply certain number per second- this is current. If you want to maintain their number on outputs- this is voltage. In any case, defibrillator works in 10-100msec range. if you want so much more- the system must be very different.

Yes, you missed that a difibrillator delivers a one off shock (not continuous charge). It has a short duration. If you wanted to deliver a current for 30 seconds just use a taser.

7:03 PM
@GregoryKornblum. Incorrect.....Defibrillators are designed to deliver a fixed charge (usually accumulated on a capacitor bank). Read this: resuscitationcentral.com/defibrillation/biphasic-waveform
@JImDearden . Tasers are almost the same as defibrillators since they deliver pulses of charge either capacitively or inductively accumulated. They do NOT deliver a 30 second pulse.

@JackCreasey i can only see several milliseconds pulses.
@JackCreasey by the way, fixed charge on capacitor means fixed voltage. Moreover, although capacitor is what makes the linkage between charge and voltage, in system design charge means nothing, voltage does.

@GregoryKornblum. Correct, your point being what? It delivers enough voltage to break through the outer skin layer, then you have a low value resistor (internal human structure) across the capacitor bank so you get a large current discharge. Advanced defibrillators attempt to do some waveform control.

Classical xy problem. Please explain in more depth what you need to know, and why, and what you plan to do.

@GregoryKornblum. So Joules means nothing?

@JackCreasey my point? What's yours :) You said fixed voltage- it's not.

7:03 PM
@GregoryKornblum. At no time did I say fixed voltage.

@JackCreasey Joules may mean whatever they need to mean, they are not equal to coulombs. Same as volts are not.
@JackCreasey i am sorry, probably it was someone else. I was sure this is what i am arguing with.

@GregoryKornblum. Perhaps some training will help: micunursing.com/defib.htm

You know, i am lucky to exit medical electronics, so i will concentrate on something else. Don't want to risk people lives :)

3 hours later…
10:11 PM
@MarcusMüller I assume you were talking to me with the XY Problem comment. I clarified the question to be a bit more specific. What I'm asking is whether defibrillators are capable only of delivering one-off "charges" or shocks, essentially (read the comments above for why I'm double quoting that), or whether a defibrillator can deliver it's intended waveform continuously, with no pauses to recharge between shocks

10:52 PM
@TheEnvironmentalist What is the goal of your project (even if it's only a mental exercise)? What are you ultimately trying to accomplish?
These are the questions that can dispel the XY problem.

11:51 PM
There's a scene in the TV show Dexter wherein the titular character electrocutes two people simultaneously with external defibrillators. He doesn't cause arrhythmias, as far as I can tell. He actually electrocutes them with extended shocks. My first thought upon seeing this was, "that's not how defibrillators work." I wanted to do some additional research just to be sure. I asked it here after googling around and not finding anything of note that actually describes modern defibrillator function.
@NickAlexeev See above.