Xenon Tube, using flyback transformer in LtSpice?

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Joined Jul 3, 2021
Hey @ericgibbs, thanks for the schematic, saves me a lot of time :)

Yeah, I'm looking at these amazing xenon phtoflash chargers ICs available in here -

Seems like all of them have an LTspice simulation circuit included, going to check these out later after work. This is awesome!

Not a lot of strict requirements, just this three below:
1. Portable and compact (very important) - preferably powered at 12V (3S 18650 cells) - this charger will be used to power a camera ring flash xenon tube for hand-held shooting outside.

2. 200W output - I saw some photoflash capacitors recently and they are very huge in size and I feel like aiming for a higher energy output will impact the overall size of the charger. This photoflash caps are only 1000uF but easily 3.5cm x 5.5cm in size.

3. Charging / recycling time preferably as low as possible (aiming for 3 seconds or less for a full 200W charge)
Is the charging time possible to simulate in LTspice with accuracy?

Looking at the above link of xenon charger ICs, I wonder what will be the important design specs and functionality of those ICs that I should focus on based on the requirements.

And does the choice of a flyback xfmr specs matter as well?, or I could just use a generic one as long as it would reach the required voltage of the photoflsh capacitor (340V~360V) ?


Joined May 20, 2015
You're wrong about power. You need to operate on the energy of the charged capacitor.
LTspice calculates the charging time correctly.
The type of transformer is important.