Pi 3B vs Pi 4 power delivery?

Does anyone know if the pi 4 deliver more power than the pi 3 or is it all about the power supply? Trying to figure a way to power the picade, 10 inch screen, usb encoder, and a 3 amp 5v amplifier.

The power supply is the main limiting factor, as far as how much current you have on offer. The official Pi 3 power supply is max 2.5A and the official Pi 4 supply is 3A max.

You’re looking at either using multiple supplies, or one large capacity supply with custom wiring. I have one of these 5V 10A switching supplies.
5V 10A switching power supply : ID 658 : $29.95 : Adafruit Industries, Unique & fun DIY electronics and kits
I cut the barrel jack off and soldered Pi compatible cables on the end.
I can run up to 4 Pi’s at once, depending on the model and what’s connected to them.

Thanks.I am just looking to keep it simple.

Where does the 3 amp 5v amplifier get its 5V from?

Having just gone through a power delivery issue with my Pi 4 and an LED project I ended up getting one of these which I can recommend.

I’m powering both my Pi and my LEDs from this unit, though you will have to do some wiring.

It is plugged into the pi. Here it is. https://www.amazon.com/dp/B077MKQJW2/?coliid=I2GG9UD1YQ3F29&colid=34NX46HTLI89D&ref_=lv_ov_lig_dp_it_im&th=1

So that amp, the 10 inch picade screen, and a usb encoder.

I am using an older pi 3b. I was wondering is a pi 4 would make a difference.

I don’t know that the Pi 4 would make much difference in this scenario.

The current from the USB ports is almost certainly limited. You might see an improvement powering the amplifier from the 5V/GND pins directly.

At the end of the day it’s all going to depend on the supply to the Pi.

I think I found my small simple solution. I ordered it and it will arrive Monday. I will respond with results. I got this.



This says it can do the trick. RPi Powered USB Hubs - eLinux.org

The reason I think it will work is my small 4 port usb charging station works fine. I just rather not use it since it’s a little bulky in the picade. See below.

So I am using the Petrockblock power block to work with the power button on the side. So I have usb power from the usb charger and the audio amplifier. The only thing I have plugged into the usb’s on the pi is the 10 inch screen and the usb encoder. With this setup I get no under voltage. So I will try the same approach when I get that usb hub. Since it is externally powered I think it will work. I will just only use 2 ports…The audio amp and pi. Should work.

12.5 Watts is only 2.5 Amps @ 5V. P = I x E

P / V = I

Well the Rav power I used is 5v/2.4a and it worked fine.

JFYI, The Official Micro USB Power Supply is Rated for 12.5W.
And the Official USB C Power Supply is rated for 15W
Buy a Raspberry Pi 12.5W Micro USB Power Supply – Raspberry Pi

Granted, you don’t get all those useful extra USB ports.

Good point. I also have this coming. It’s 20w 5v 4a…i would assume it will do.

Geekworm Raspberry Pi 4 Power Supply, 20W 5V 4A USB C Power Adapter Type C Fast Charger UL Listed Support Raspberry Pi 4 Model B/NASPi/DACPi/X-C1/X825/X735/X728/X708/X706/X703/X930 https://a.co/d/b0Ll5bC

Well this seemed to do the trick. No low voltage warning. I have the 1 plug from this 20watt 5v 4a power supply that goes to the power block. Then I have the USB encoder, 10 inch screen, and audio Amp plugged into the pi usbs. Worked great. No low voltage warning.

Is it better to have a power supply with 18w 5.25v,3.5a or 20w 5v,4a?

There is a Max Voltage limit on the +5V. I can’t at the moment find where its documented, but 5.25 V might be too high?
It should be listed here somewhere.
Raspberry Pi Documentation - Raspberry Pi Hardware

Would 30w 5v 6a be too much? I was thinking of maybe trying this.

with this adapter going into my Pi. This adapter is only for 5v so it’s perfect.

This is what is on the back of my picade to connect to my pi.

As long as it’s 5V and can supply enough current to drive what’s connected, all is good. Being able to supply more current than what is needed isn’t a problem. The load (Raspberry Pi etc) will only draw what current it needs.
The usual problem is all you blinky bits want more current than the Power Supply can deliver.

Short answer, no it won’t be too much.

OK that’s perfect. Currently my 20w5v4a solution is working fine but when I add the fanshim or crank the volume up it does low voltage. It’s OK for now I think long term I will go that 30w5v6a route. I can’t go higher because the petrockblock power block can only handle up to 7a. Thank you for your replies. I also hope it helps other that may read this.

It’s counter intuitive, but the undervoltage indication is often caused by an overcurrent event. A good quality Power Supply will automatically reduce the voltage to prevent an overcurrent. If you try to exceed its rated maximum current, it throttles back the voltage to prevent it.

There are a few other threads along these lines. Also dealing with the Picade Console.
I’m not knocking the Picade Console per say, just that powering what you build can be an issue. And trying to have “one” on off button / “one” power supply.

Even more so if you’re trying to run something from a battery. Especially if it’s Pi based. You have to boost the LIPO’s voltage to 5V. Most times, with an RP2040, you can power it directly from the battery.
I’m lucky in that I can modify what I buy to make it fit for purpose. Getting out the wire cutters, soldering iron, and heat shrink, is not a big deal for me. I do get that it is an issue for some though.
My best advice is, if there is any skill that will help you the most, its learning to properly solder components etc.

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