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I'm not aware of any pulse machine which uses a photocoupler in the MOSFET drive circuit for the coil. Anyone ever explore such a thing.
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I'm sure I have seen schematic that used a photocoupler between a microcnntroller and the coil MOSFET.
Probably saw it on this forum.
The only reason it was used was because the microcontroller and MOSFET were on very different 'grounds'.
It was used more as a 'domain level shifter'.
Then there is KingJL's Bipolar PI that uses transformers to isolate the control processor from the TX Coil MOSFETs.
https://www.geotech1.com/forums/show...-and-Front-End -
I saw there are specially designed optocouplers for driving mosfets. The power supply for the mosfet are separate as you pointed out in the example you cited.Comment
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There are a few circuits that use them, https://docplayer.org/23853098-Pulsd...inipuls-3.htmlComment
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I did some searching on combined optocouplers+mosfet drivers a while back and found the FOD3182 which I liked the most based on specs. 10 V min supply voltage and good rise/fall times among other things.
Used it for TX like this in my direct preamp sampling with ADC experiment:
https://www.geotech1.com/forums/attachment.php?attachmentid=49249&d=1579710666
From what I could tell it worked well and simplified the drive circuit a lot. Can't comment on the performance though as I don't have a scope and my ADC sampling circuit wasn't particularly sensitive. I'll use it again for my next detector build where I'll go the usual analog integrator route.Comment
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Yes, that looks nice and simple solution for driving the MOSFET from a micro source, provided that it actually works good. Otherwise you might require 2 or 4 transistors for a proper drive circuit, depending on the topology.
Perhaps it's something worth exploring further, although I'm sure other more experienced members may have done so already.Comment
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