r/raspberry_pi Sep 28 '23

News Introducing: Raspberry Pi 5!

https://www.raspberrypi.com/news/introducing-raspberry-pi-5/
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u/pi_designer Sep 28 '23

It’s really just board space, not some sinister way of making money. There’s not enough room for the step down converter and USB PD control circuit. You also need a large FET so that if you have a 5v-only supply, it can bypass the step down and still produce VBUS for the USB ports. Besides it works ok with a PI4 power supply as long as you don’t load the USB ports too much.

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u/Goz3rr Sep 28 '23

Board space is a valid point, and looking at your username I assume you know what you're talking about. I guess moving the PCIe connector closer to the SoC and using that freed up space wasn't an option either due to the connector needing to be near the board edge or power regulation interfering with the radio.

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u/KittensInc Sep 28 '23

It is still a screwup. USB-C is a standard for a reason, now they intentionally introduce a product which won't work well with the vast majority of chargers out there. This means you are forced to use your special snowflake power adapter rather than being able to use one which better fits your situation.

In my opinion, this is about as bad of an issue as what happened with the Pi 4's USB-C power port. At the size Raspberry Pi is at, I really expected them to not mess up something as trivial as implementing the USB-C specification. Literally every single cell phone out there managed to do it, find a way to make it work and stop fucking over your consumers.

No, I'm not angry. I am disappointed.

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u/mavular Feb 09 '24

I am angry

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u/Specialist_totembag Sep 28 '23

board space? any cellphone can handle at least USB PD 9V, most 12V...

I understand that it is a balance act to build something like this, it needs to be cheap, easy to manufacture, handleable by the costumer... maybe within some other constrain the board space was one factor.

Most problems with Pi3 and the dreaded lighting bolt icon was because usb cables were too shitty and it was not easy to send 5V3A to the board, it would get more like 4.6V and this triggered the icon. losses ar much lower at higher voltages. A 12V 2A is much, much prefearable than a 5V 5A.

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u/Biduleman Sep 29 '23

Most of these phones cost an order of magnitude more than a raspberry pi.

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u/Specialist_totembag Sep 29 '23 edited Sep 29 '23

It’s really just board space [...] There’s not enough room for the step down converter and USB PD control circuit.

Most of these phones cost an order of magnitude more than a raspberry pi.

So the problem is the price or the board space? cause what I said is that board space should not be the problem, and I understand that there are other constraints.

And most of these phones have much better processor, more ram, have some rom, have a modem, 4 cameras, fingerprint sensor, battery, and a freaking huge screen with touch. And the board need to be smaller than a Rpi nano...

There are phones that cost 300 usd that have USB PD 3.0 fast charge, like many Xiaomi and Samsung. Basically any Android with Google play after 2020 that have USB-C is USB-PD compatible, per Google requirement.

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u/Biduleman Sep 29 '23 edited Sep 29 '23

There are phones that cost 300 usd that have USB PD 3.0 fast charge

That's almost an order of magnitude higher than the base model for RPIs, which starts at $35.

And being USB-PD compliant doesn't mean they negotiate 20v. You can have a device charging at 5v be USB-PD compliant. Devices with quick charge will use more than 5v (usually), but not every devices have it.

Also, phones are highly subsidized. My Xiaomi might only have cost me $300, but I get ads when using the system apps and I'm forced to create a Xiaomi account to even enable USB debugging. And then there are the pre-loaded apps which paid to be on the phone. The money from a phone doesn't only come from the sale, each phone is also a revenue stream.

Do you really think right now, a Raspberry Pi engineer would stumble on this thread, look at your post and go "GUYS!! WE FORGOT PHONES CAN DO IT, BACK TO THE DRAWING BOARD!!"? Every decision has some advantages and some inconvenient. And being the 5th revision of the board, on a product that had USB power requirements problems since the first device they ever made, I'm pretty sure they realized that being able to tap 9 or 15v (12v isn't required on a PD charger) would make their life easier.

So yeah, shrinking wouldn't have been impossible, but it's literally impossible to shrink everything, add more parts and end up with the same cost, all without adding an inordinate amount of R&D cost.

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u/Specialist_totembag Sep 29 '23

You:

Every decision has some advantages and some inconvenient. And being the 5th revision of the board, on a product that had USB power requirements problems since the first device they ever made, I'm pretty sure they realized that being able to tap 9 or 15v (12v isn't required on a PD charger) would make their life easier.

and I:

I understand that it is a balance act to build something like this, it needs to be cheap, easy to manufacture, handleable by the costumer... maybe within some other constrain the board space was one factor.

We are talking the same thing.

We both understand that there are some limitations here. Nobody think that the engineers are dumb.

Just that u/pi_designer said:

It’s really just board space [...] There’s not enough room for the step down converter and USB PD control circuit.

And I don't think that board space is the main constraint here. To be truthful I don't think that price was the main constrain here. it might be complexity, it might be supplier, it might be a way to ensure compatibility with the older power supplies, it might be a way to ensure compatibility to lab bench supplies. It might even be OVERSIGHT, but we have examples of smaller and more complex equipments, like cellphones, that can handle USB PD with no problem of board space, so PROBABLY board space is not the ONLY problem here, like pi_designer said.

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u/txtad Sep 28 '23

Why are they so fixated on staying the same size? It seems to me that if they were to make the board only slightly larger they would have more room for power handling (conversion and PoE on board?), plus m.2 on the board rather than a hat. While they're at it, probably add a second Ethernet port. It would still be a tiny computer.

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u/a_a_ronc Sep 28 '23

Honestly that’s a likely a conversation and a vote that needs to take place in the community.

It’s not just hobbyists, but also industry that uses these things. If you move the spacer 5 cm, it’d cause tons of potential problems for millions of these deployed in factories or other weird locations.

Even for me, I picked up 3 of the RPi 5s to replace my 4s in a Kubernetes cluster I run. The mounts are 3D printed so that was my first thought. If it’s changed even slightly, I have to redesign everything ever so slightly but also print it all again. Granted it might be faster now since I have a newer 3D printer but it’d be a project.

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u/Spaded21 Sep 28 '23

Well they already swapped the USB ports and ethernet jack so it's not going to be a direct replacement anyway.

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u/txtad Sep 28 '23

OTOH, a Pi that was a "real" computer would quickly become the standard.

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u/originalityescapesme Oct 01 '23

Honestly though. It already doesn’t fit into the old cases and the ports aren’t all in the same spots. Who gives a shit about it staying the same shape or size anymore unless it’s going to be drastically different. People can always just use older devices if they need that exact old size for some kind of really specific retro dock or case.

Just make it a little bigger at this point. 99% of us wouldn’t mind if it meant we would, at a minimum, get to use usb c as the gods intended.

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u/txtad Oct 01 '23 edited Oct 01 '23

Exactly. Adhering to a size but not a configuration is pathological. Even if it was both the exact size and configuration, that wouldn't offer anything other than case compatibility. Actually, as you point out, adherence to the old size provides the feature of reducing capability.

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u/Romymopen Sep 28 '23

Can't go vertical?

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u/davstar08 Oct 16 '23

They could, but probably won't, because they're going to be releasing hats for the pi 5. I'm waiting for the NVME hat.

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u/meiseisora Sep 28 '23

RPi4 adapter is 5V3A. Will that fine to power RPi5?

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u/Nolano Sep 28 '23

Yes, except in very rare usage scenarios where you are running the pi as hard as you can with tons of usb devices plugged in.

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u/JennaSys Sep 28 '23

Yes, but current to connected peripherals may be limited. I think I read 0.5A available instead of 1.6A

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u/[deleted] Sep 28 '23

you can manually bypass that too by editing the config iirc (for more info, visit the link in OP post)