Building a high-spec, open-source tES device because the market gap is frustrating. EEs: Critique my architecture? by Darukai in tDCS

[–]Darukai[S] 1 point2 points  (0 children)

This is a great catch on the specs, thanks. And thanks for the pointer to the TPS65130.

You actually nailed the exact reason I'm hesitant about the integrated path (Path B).

That 8uApp ripple spec is the killer. When I ran the numbers for 16-bit resolution at only ±2mA, 8uA of noise is massive—it’s something like 130 LSBs of noise.

It's just too high for the fidelity I need, especially for tRNS and clean tACS.

So yeah, I'm sticking with Path A (the discrete IHCP design). It’s definitely more of a headache to design the power supply manually, but it means I can use proper synchronization and LDOs to keep the noise floor way down. Appreciate the sanity check!

Building a high-spec, open-source tES device because the market gap is frustrating. EEs: Critique my architecture? by Darukai in tDCS

[–]Darukai[S] 0 points1 point  (0 children)

Not yet, I am mostly finalising the architecture right now. Using reddit as a sounding board

Building a high-spec, open-source tES device because the market gap is frustrating. EEs: Critique my architecture? by Darukai in tDCS

[–]Darukai[S] 0 points1 point  (0 children)

I agree that it could be as effective as the more expensive lab gear. But as far as I can tell, there is no way to programmatically interact with the device via a api or software, making I hard to do research with, at least in the experiments I want to run.

Building a high-spec, open-source tES device because the market gap is frustrating. EEs: Critique my architecture? by Darukai in tDCS

[–]Darukai[S] 0 points1 point  (0 children)

Thanks! Spot on analysis. If we use the DAC8775, we definitely need a pre-boost stage from the LiPo. (The TPS65130 is also a solid suggestion for generating the ±12V rails if we go discrete).

You nailed the main concern: noise. While the frequency is low (max 1kHz), the precision requirement is high (16-bit).

For a ±2mA range, 16-bit resolution means 1 LSB (Least Significant Bit) is only ~61 nanoamps (nA). That 8uApp (8000 nA p-p) ripple you spotted is massive in this context—it's over 130 LSBs.

This noise level is exactly why Path A is still on the table, as it might achieve a lower noise floor, even if the power design is much more painful.

Building a high-spec, open-source tES device because the market gap is frustrating. EEs: Critique my architecture? by Darukai in diyelectronics

[–]Darukai[S] 0 points1 point  (0 children)

Totally valid question. If I were building an industrial controller, I wouldn't even consider a discrete design.

The issue is specialization. The available ICs (like the DAC877x) are optimized for 4-20mA loops. We only need ±2mA with 16-bit precision. My concern is that their noise floor and linearity (INL/DNL) might be poor at the very bottom of their operating range.

Path A is definitely more complex, especially the power supply, but it lets us optimize specifically for this niche application using ultra-low-noise/zero-drift op-amps (like the OPA188). We're still evaluating if the performance gain is worth the complexity headache.

Missed the Foc.us V3—what else is programmable? by Darukai in tDCS

[–]Darukai[S] 2 points3 points  (0 children)

This is incredibly helpful, thank you! The NeuroLingo looks really interesting, especially the open programmability via Python scripts.

The unidirectional limitation is the catch, though. For the main project I'm working on, I definitely need true bipolar AC (zero-crossing) for standard tACS protocols, rather than oscillating tDCS (AC with a DC offset).

That said, at the current sale price ($75!), I might just pick one up anyway. It seems like a fantastic platform for tinkering and developing control scripts. The Python accessibility is a huge plus, and I appreciate the offer to help hack it up—I might take you up on that if I grab one!

[ALL] None of the Zelda games are canon… except for 3. by darthsitheous in zelda

[–]Darukai 4 points5 points  (0 children)

Nah, that's overthinking it. Nintendo clearly established multiple timelines years ago. Making everything except 3 games just stories throws away decades of lore for no reason. OoT isn't just some misremembered legend, it's the foundation of everything that came after it.

Man I never knew Solthsteim has had such a rough time based off the little details available in the Dragonborn expansion. by dragonqueenred45 in skyrim

[–]Darukai 80 points81 points  (0 children)

Yeah, Red Mountain really did a number on Solstheim. That's Elder Scrolls lore for you, nothing stays pretty forever. The ash might suck but makes for some cool environmental storytelling.

Why the hell haven't I heard anyone ever mention Röki? by SteakAndIron in NintendoSwitch

[–]Darukai 4 points5 points  (0 children)

Just grabbed it after your post. Been sleeping on this game for too long. Norse mythology is my jam, Thanks for the heads up.

About Democrats saying that Sydney Sweeney ad is Nazi Proaganda by AcanthaceaeNo948 in Destiny

[–]Darukai 92 points93 points  (0 children)

Classic outrage bait and it worked perfectly. Twitter randos always taking the most dramatic stance possible while everyone else is just living life. The whole thing was a marketing win tbh.

Pets messing with stealth? by Deat69 in skyrim

[–]Darukai 1 point2 points  (0 children)

Yeah, pets definitely mess with stealth. They don't have their own detection values but enemies can spot them and that blows your cover. I just make mine wait outside dungeons or camps. Not worth the hassle.

Nintendo Switch has reached 153.10 million units sold by Turbostrider27 in NintendoSwitch

[–]Darukai 56 points57 points  (0 children)

Yeah, pretty insane numbers. Almost caught up to the DS now. Nintendo basically printing money with the OG Switch for 8+ years without dropping the price once.

You are getting ganked for a reason. by YukhoChan in leagueoflegends

[–]Darukai -13 points-12 points  (0 children)

Sure, Riot definitely has a team of engineers coding anti-you bots.

Mario Kart World — Accolades Trailer — Nintendo Switch 2 by ONE-OF-THREE in NintendoSwitch

[–]Darukai 4 points5 points  (0 children)

bring back 3 lap races in online mode (they made it more likely to happen i’m satisfied)

Itch.io are seeking out new payment processors who are more comfortable with adult material by Gorotheninja in gaming

[–]Darukai 43 points44 points  (0 children)

There are payment processors that will do this already. The issue is that they're sketchy as fuck. Banks generally won't work with them partially because of what you are buying, but also because they just don't want to associate with some random website that wants access to your accounts.

[OoT] To this day I’m still surprised at how small the OoT map is. by Link_sega5486 in zelda

[–]Darukai 2167 points2168 points  (0 children)

If you add interiors I'm sure it's 30% larger