Dont undersant capacitor's basic principe

alphadog said:

OK i read about this step-up voltage circuit (i didnt know about it before),
But still there's something wrong with your theory.

If the capacitor's charge is 10^-5 * 350, and the discharge time (5*RC) is 0.01sec, then it doesnt mean that the current that will flow through the flash is 10^-5 * 350 / 0.01, becaues the current is not constant, but exponantial, so how can you say that, and afterwards compare it to a battery which DOES produce constant current?

EDIT:
and what does that mean:
"Let the eff=100% for the step up ratio of 350/10 = 35 times, assuming 350Vdc on the cap
"

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If you read my posts carefully, I'm not comparing the 'constant' voltage of a battery with the 'exponential' discharge voltage of the capacitor.
I'm comparing 'Q'

The efficiency is assumed to be 100% for the circuit that converts from battery to capacitor charging voltage for the purpose of explanation ONLY,
as is the step up ratio.

You dont seem to have a grasp of basic electronics theory.
Exactly what course in electronics are you studying in your 3rd year.???

ericgibbs said:

If you read my posts carefully, I'm not comparing the 'constant' voltage of a battery with the 'exponential' discharge voltage of the capacitor.
I'm comparing 'Q'


The efficiency is assumed to be 100% for the circuit that converts from battery to capacitor charging voltage for the purpose of explanation ONLY,
as is the step up ratio.

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Its so hard, i just dont get it.
I'll read about how flash works now and will reply to you on that when i finish reading it.

ericgibbs said:

You dont seem to have a grasp of basic electronics theory.
Exactly what course in electronics are you studying in your 3rd year.???

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I finished second year with 95% of success (havent start 3rd year yet), and taken courses in semiconducters (basic - diodes, BJTs, MOSFETs) and electrical circuits (basic - inductors, capacitors, etc.).

I know all about the mathematics of the electronics, but i dont know how to use it for things that i havent earned an experience in them.

hi,
It can be hard to pick up, but you seem quite determined to understand which is good.

Ask away, we will do our best to fill in those gaps.

ericgibbs said:

hi,
It can be hard to pick up, but you seem quite determined to understand which is good.

Ask away, we will do our best to fill in those gaps.

Click to expand...

Thank you, and i very appreciate you helping me out.

I've read about how flash works.
The capacitor is used in order to apply fluctuating current on a transformer, which boosts the 200V capacitor's voltage to 4K voltage applied on the metal plate of the flash which inonizes the xenon gas and creates a flash.

What i dont understand is where is the "high-speed use" in the capacitor?
If the time it took to the capacitor to discharge was longer, then for the transformer to work you will need the secondary coil to have more loops, because dΘ/dt would have been lower?

alphadog said:

What i dont understand is where is the "high-speed use" in the capacitor?
If the time it took to the capacitor to discharge was longer, then for the transformer to work you will need the secondary coil to have more loops, because dΘ/dt would have been lower?

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The time it takes the cap to discharge thru the flash tube is much shorter than the charging time.

The step up transformer does have more turns on the secondary winding than the primary winding.

ericgibbs said:

The time it takes the cap to discharge thru the flash tube is much shorter than the charging time.

The step up transformer does have more turns on the secondary winding than the primary winding.

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Thank you very much.
I understand now very well the flash issue.
One day when i tell my kids about it, i'll tell them that some Eric Gibbs dude has taught me that

Next thing on my target: Buck & Boost converters

better start with a complete understanding of how an inductor works

OutToLunch said:

better start with a complete understanding of how an inductor works

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yes

Hey, do you live near the place where Dawsons Creek was filmed?