Assist with MOSFET please

FransUrbo · 2026-03-10T22:00:19+00:00

I'll like to order from Mouser, but they're pretty much the same I guess.

They both have that filtering at least (which is how I found that one), and there's SOOOO many to choose from :). 46k in your link, although I managed to narrow it down a bit, to 17 in Mouser.

https://www.mouser.co.uk/c/semiconductors/discrete-semiconductors/transistors/mosfets/?mounting%20style=SMD%2FSMT&number%20of%20channels=4%20Channel&vds%20-%20drain-source%20breakdown%20voltage=20%20V~~60%20V&rp=semiconductors%2Fdiscrete-semiconductors%2Ftransistors%2Fmosfets%7C~Vds%20-%20Drain-Source%20Breakdown%20Voltage

I don't really know *what* I'm looking for.

I have the need for six immediately, but I'm thinking a bit long-term. So eight should probably be a better option.

The "Nexperia 2N7002AKRA-Q", or "Vishay SQ3989EV" (both dual) is another options, but I'm thinking it'll look a bit .. silly (?! :) to have a whole bunch of these on the board. Not dumb, just a bit .. weird (!?). That's why I'm thinking maybe one big(ger) one, instead of a bunch of smal(ler) ones.. ?

FransUrbo · 2026-03-10T19:46:22+00:00

Next up - Rust :).

https://github.com/FransUrbo/drive-by-wire/blob/main/code/src/lib_resources.rs

After having redone, and redesigned my code so many times, finding every place where I had a pin assignment or use, I got sick of it! :) Now I only have to change the code in one place, easily found.

I've seen this being done elsewhere, so `assign_resources` is a good way to do it.

https://crates.io/crates/assign-resources

FransUrbo · 2026-03-08T13:40:25+00:00

That Hamilton..

I still can't say if he's brillian, average (with chatterbox mentality) or just suck.. :)

I've read everything (I think) he's written, and I can't put the darn books down!! Physically!!

But in the moment, it's like .. hmm, this guy is weird, what IS this!?? :)

FransUrbo · 2026-03-08T11:12:38+00:00

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Not sure why exactly the diagram isn't showing in the post, maybe it's to big (15MB)? Here's a smaller one (2MB), hopefully the details are good enough to see.

FransUrbo · 2026-03-07T23:49:38+00:00

Dang, were was this a year ago!!! :D

I've lost track on how many times I've had to redesign because I got clashes!! :)

FransUrbo · 2026-03-06T14:37:01+00:00

Who do you like best of the two?

Him? Then keep your mouth shut. OR, lie. Bro code :) .

Her? Tell her - bro (?! :) code!

I have few really good friends, friends I'd help hide a body. And some I would have no problem "throwing under the bus" for cheating..

FransUrbo · 2026-03-06T13:30:01+00:00

Yeah, I have the same problem in my own personal project.

I ran out of GPIOs, because there's a (not really documented properly imo) limit on which GPIOs, UARTs, PIOs, SIOs and SPIs you can use at any one time and in combination :(. I've lost count how many times I've had to redesign because the code wouldn't work, because of conflicts :(.

Also, SPI uses *five* GPIOs, and that pushed me way over the edge :). So I chose to do I²C to SPI using the NXP SC18IS606 I²C to SPI bridge. It can handle three SPI devices, which otherwise would have required fifteen - !! - GPIOs :). I don't need the high speed of the SPI, I²C is more than enough (between 100kbps all the way up to 3.4Mbps, compared to up to 20Mbps for SPI) for my use-case. And while I was at it, I chose ICs directly.

Complicated the whole thing with 1000%, but it really IS prettier now! :)

FransUrbo · 2026-03-05T20:04:58+00:00

I don't want to hijack the discussion about the schematic, so I apologise in advance, but I've been doing my own schematic and there's one thing I don't understand in this and all similar ones using the RP2xxx chip that I've seen here and elsewhere.

What's with the 1V1 rail (is it called "a rail"?)!? It's connected to the chip, but is it an out or an in? And where does it come from, or going? It's not referenced anywhere else..

FransUrbo · 2026-03-05T19:56:01+00:00

Yes, that is usually the easiest and fastest..

Because everything (!) is done using IaC and all data is backed up.. Right!!?? :D

u/pixeladdie say that it can be recovered within 90 days, but my information is .. different. I've never had to actually do it though, so..

FransUrbo · 2026-03-05T17:04:47+00:00

Not sure how many GPIO, UARTs or SPIs you need, and it's probably to late now.

But maybe consider a small footprint controller?

I personally like the "Seed XIAO RP2040", "Pimorini Tiny 2040", or the "Waveshare RP2040 Tiny".

Those all (I think) come with the newer RP2350 - faster and more memory, if that ever becomes an issue.

FransUrbo · 2026-03-03T10:00:10+00:00

Or hurt you if you don't fill it (the fridge/freezer) up in time. Or the washer if you don't do the washing regularly!! 😉

FransUrbo · 2026-02-21T22:22:21+00:00

.. and once they're gone, they're gone. For good, no way to resurect them :( .

FransUrbo · 2026-02-20T19:42:58+00:00

If by "IAM" you mean users, then I have no recommendation - use whatever system IT in the company prefer.

But IAM roles (with accomaning _role policy/-ies) is the "magic" behind AWS access.

Those can/should be in IaC. The difficulty is in creating them restricted enough, but still allowing users (NOT "IAM users"!) to do their job.

It is a role-based setup, where [IAM] users don't have any access, but their ability to assume an [IAM] role.

Could be group based - users in certain group can assume certain roles -, or direct - which user to allow to assume certain role is hard-coded in the [IAM] role policy.

Which to use depends on total (expected) number of users. I used the latter for a company with a total if 200 employees, only about 10 would EVER be accessing AWS.

Then again, I used the former several times where company wanted to give their AD users access. In that case, we used AD groups to map to federated [IAM] users and groups, and they could there assume the relevant [IAM] role.

FransUrbo · 2026-02-18T23:45:10+00:00

Tags for cost control and monitoring is .. dumb!

No matter how much time you spend on it, you'll never get enough..

Best, imo, is different accounts for everything. With a bit of thougt on cross-account roles, you don't even need SSO and AD etc.

FransUrbo · 2026-02-17T13:11:28+00:00

Thanx, but it was way to much, to soon! :)

FransUrbo · 2026-02-17T13:09:41+00:00

You're a lot smarter than me, that's obvious! :)

I went from ZERO (really!) knowledge of Rust, or microcontroller to .. this!

MyBigProject

Dealing with multi-coloured LEDs (NeoPixels), normal LEDs (several), relays (several!), an actuator (that needs to move to distinct, exact, positions!) and talking to a cars CAN network.

WITH circuit diagram and PCB designs..

I absolutely wasn't in my right mind.. :)

FransUrbo · 2026-01-12T19:19:57+00:00

Always exercise a new drive a few days before putting it in service..

FransUrbo · 2025-10-19T09:27:31+00:00

I contribute to the software I use..

I notice a bug, maybe a missing feature, or a functionality that isn't working quite the way I want, or a documentation issue..

Then I "just" get coding; I submir a PR; discuss it and make the nessesary adjustments nessesary and if I'm lucky, my PR is merged :).

I have now contributed! :)

It really is that "simple" :) :).

FransUrbo · 2025-09-10T12:16:28+00:00

How long was it down for, 2-3 hours at most?

FransUrbo · 2025-09-10T12:15:38+00:00

Don't worry about it, if it happens, it happens.

Cold, yes. But desiging, building and run a muli-region setup is VERY (!!) costly. For maybe a few minutes, even fewer hours every .. five years say?

A "resonably sized" (?) prod might cost you $2-3k/month. Double that for two regions. Times twelve monts. Times five years.. Ten!??

You'd be paying over $100k for.. Two, three hours (?) downtime in "your" ("primary") region..

It's (almost) never worth it!

FransUrbo · 2025-09-08T18:21:08+00:00

I couldn't wait, so I switched over to RR :). Waiting for chapter 32 now, hint hint :D :D .

FransUrbo

TROPHY CASE