Thyristor Gate in a camera flash

[PhilC]

Hello,
First time poster here, I recently replaced the Xenon flash tube in a friends Yongnuo YN600EX-RTII camera flash, it has been working great.
However it developed a louder pop than usual recently and I found the the magic smoke has been released from a small SMC capacitor that is across the Thyristor gate and Cathode and in parallel with an SMD LED. The flash is still working.

I have removed the damaged capacitor from the board to stop the sparking/electrical flash (the loud pop).
My question is what is the purpose of this capacitor is it just for the LED, e.g can I just remove it and not have to replace it. The LED is not functioning either.
As from my limited knowledge it is not essential for the Thyristor gate
I have requested the circuit diagram from the manufacture, however I don't expect a response from them.

Included is a photo of the component and the link to the spec sheet for the thyristor.
https://www.renesas.com/us/en/doc/products/transistor/005/r07ds0332ej0301-cr5as12a.pdf

Any guidance would be greatly appreciated.
Many thanks
Phil

[schmitt trigger]

I can't read any numbers from the "thyristor" package.

Are you sure it is a SCR and not an IGBT?

IGBTs allow tho control of the flash duration, thus controlling its total integrated light output.

[PhilC]

According to the linked spec sheet it is a Thyristor it is a CR5AS12A

[schmitt trigger]

I have read the datasheet...it is a SCR.

Let me re-phrase my question: Since there are no visible numbers or letters in the DPak device, how did you surmise it was that particular Renesas part number?

[PhilC]

The photo doesn't show the part number unfortunately, but the part number is clearly visible and hence my reference to the data sheet.
Thanks for being so through and checking.

[flolic]

Take a look here:
https://impulsite.ru/viewtopic.php?f=10&t=1222&sid=26c9b95fb40a8e994bbeb722c57a7d46

You can use google translate

[PhilC]

Thanks @flolic for the link, that has help with the circuit diagram now attached to this post.

I my instance it is the capacitor 302 that has failed. What I am trying to identify is what is the purpose of this capacitor is, is it only there for the LED D303.

Thanks all so far for you help
Phil

[TerminalJack505]

The cap is there to dump a little extra charge into the gate so that the thyristor turns on fully.  I'm guessing it is around 100nF.  The LED must be there as a poor-man's voltage clamp so that in the case the thyristor doesn't trigger the voltage on the gate (and across the cap) is limited.  Most thyristors will trigger at ~800mV so the cap doesn't need to have a particularly high voltage rating and the Vf of the LED will need to be greater than this.  The circuit may work fine without these components but I would replace them just to be on the safe side.