LASCR anyone?

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The recent posts about phototransistors got me remembering about working with LASCR's, maybe 30 years ago.  They are Light Activated SCR's & I used to make camera flash detectors for my friends.  They were pretty cool devices.  I thought maybe I might order a few to mess with, but can't seem to find any part numbers...does anyone know of any Light activated SCR part numbers (that you can order)?  I found a few "ancient" numbers, like GE-23 or similar.

 

Have the LASCR parts disappeared? 

 

I also thought Sensefets were pretty cool & used them in several designs, but sadly they seem to have largely evaporated as well.  Sensefets have/had two extra terminals to sense the current flow in a small copied array of internal fet cells..so no sense resistor needed.  There were more and more of them becoming available, but perhaps they never took off; now there are only ragged remnants.

 

Maybe they join the list of "former device types" (maybe EPROMS will someday join them)

When in the dark remember-the future looks brighter than ever.   I look forward to being able to predict the future!

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Yeah, I have fond memories of LASCRs, and I've noticed that they essentially disappeared.
I also never figured out whether they were good for anything OTHER than that ubiquitous flash slave...

Or whether they'd even work with a modern flash.  Or what the modern equivalent circuit it (other than "buy our intelligent flash system that costs as much as your camera.")

 

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Decap a C106 and see how you fare with its light properties.

 

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I found an old motorola LASCR  part number:  MRD920   ...but data is scarce.

There is an oddball place that has some "mrd920" in stock....but they could be something else, like screws.

 

It seems, as suggested, you might pop open a LASCR/photothyristor/photoscr coupler & pump in some light yourself.

 

There are some BIG devices (light triggered thyristor) out there, for very high power apps:

 

https://www.infineon.com/dgdl/In...

When in the dark remember-the future looks brighter than ever.   I look forward to being able to predict the future!