[sdiy] anti pop mosfets in minibrute

[Chris McDowell]

Hehe that would be funny as they're even drawn in the schematic symbol! and labelled 2n7002. Yves Usson did this fella, if I'm understanding the internet correctly. 


> On Apr 24, 2024, at 4:30 PM, Mike Bryant <mbryant at futurehorizons.com> wrote:
> 
> My guess would be those are the actually specialist MOSFETs without the body diode.  Rare but they do exist.
> 
> Or it's just a poor design 🙂
> From: Synth-diy <synth-diy-bounces at synth-diy.org> on behalf of Chris McDowell via Synth-diy <synth-diy at synth-diy.org>
> Sent: 24 April 2024 21:14
> To: SDIY List <synth-diy at synth-diy.org>
> Subject: [sdiy] anti pop mosfets in minibrute
>  
> <preview.png>
> MiniBrute-10-OUTPUT
> PDF Document · 339 KB
>  <https://hackabrute.yusynth.net/MINIBRUTE/digital-board/schematics/MiniBrute-10-OUTPUT.pdf>MiniBrute-10-OUTPUT <https://hackabrute.yusynth.net/MINIBRUTE/digital-board/schematics/MiniBrute-10-OUTPUT.pdf>
> PDF Document · 339 KB <https://hackabrute.yusynth.net/MINIBRUTE/digital-board/schematics/MiniBrute-10-OUTPUT.pdf>
> 
> hello list, I've been looking at minibrute schematics today and I'm puzzled by the anti pop circuitry in the headphone driver. it -seems- like the body diode of the mosfets would conduct when the signal went below 0.6ish volts (something I've run into this using mosfets for dc signal muting).
> 
>  From the vca page, that signal can be up to 2Vpp.  https://hackabrute.yusynth.net/MINIBRUTE/analog-board/schematics/MiniBrute-08-VCA.pdf
> 
> What am I missing here? Is 2Vpp just fine in this case? Now reading the 2n7002 datasheet I see the forward voltage of the source-drain diode is typ 0.88V, 1.5V max. Did I just answer my own question? 😜
> 
> Cheers,
> Chris McDowell

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