HELP with flash quenching IGBT/MOSFET

[KD]

Hey guys,

Need help in finding an appropriate MOSFET/IGBT to pulse my hi energy flash
lamp.

I currently have a 100Ws rated flash lamp running at 330V / 1620uF (88Ws)

I'm want to do pre-flash followed by the main flash so I decided to use a
MOSFET to drive the trigger transformer and pulse shapping directly.

http://optoelectronics.perkinelmer.com/content/ApplicationNotes/flashlightingappnote.pdf
(page 3)


I've been using a MOSFET with ratings of 500V and 48A continuous/192A
pulsed. However, these MOSFETS have been dying on me after around 100
flashes... I did a current test flash pulse on them and found that it drew
about 70A peak with a pulse duration of around 15ms.

Is my MOSFET rated correctly???

If not, what rated MOSFET should I use??

What's the difference between an IGBT and MOSFET? I also used an IGBT (rated
for 85A continuous ) in place of the MOSFET and it failed to trigger with a
logic signal directly from the microcontroller (5V). I then tried to
manually trigger the IGBT with a 7V source and it only flashed once -
assumed I blew the IGBT... what am I doing wrong?

thanks...

 

[Phil Allison]

"KD"


** Stop SHOUTING !!!


Plan on blowing a lot of fets up.

Or electrocuting yourself.

Or both.


......... Phil

 

[KD]

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:40mhn1F1amg20U1@individual.net...

"KD"


** Is that an IXFK48N50 at circa $75 each ??

YES

Is my MOSFET rated correctly???

If not, what rated MOSFET should I use??


** A bigger one.

HOW MUCH BIGGER?

What's the difference between an IGBT and MOSFET?


** Oh dear.........

I KNOW... BUT CAN YOU USE THE SAME DRIVER CIRCUIT? ARE THEY INTER CHANGABLE?

I also used an IGBT (rated for 85A continuous ) in place of the MOSFET
and it failed to trigger with a logic signal directly from the
microcontroller (5V).


** Oh deary me ........

YEAH I KNOW.... I PLAN TO USE OPTO-ISOLATORS...