Nakedible
Posts: 2
Joined: Mon Oct 01, 2012 11:54 am

Maximum power input via the 26-pin GPIO header on Rev 2.0?

Mon Oct 01, 2012 12:06 pm

Hello,

I am wondering, what is the maximum current that should be provided if powering the entire Raspberry Pi board over the +5V pins on the 26-pin GPIO header?

This is on the Rev 2.0 board, where the USB polyfuses have been removed. The input power obviously bypasses the 1.1A polyfuse on the normal USB power input. It has been said separately, that providing 2.5A from the USB-A ports should be safe, but there was no mention whether the PCB traces are the same width going to the GPIO header.

Is it safe to input 2.5A on the +5V pin, having the Raspberry Pi take 700mA and each USB port giving out 900mA? If not, what is a safe value? It is assumed, that inputting 1.1A on the +5V pin should atleast be supported, but that leaves only 200mA for each USB port.

I would love to get a definitive answer, as I have already received guesswork answers saying that it should probably be safe.

Thank you in advance.

techpaul
Posts: 1512
Joined: Sat Jul 14, 2012 6:40 pm
Location: Reading, UK
Contact: Website

Re: Maximum power input via the 26-pin GPIO header on Rev 2.

Mon Oct 01, 2012 1:26 pm

Well I can really add is that the GPIO header and its associated connectors are normally rated as 1A pins.

As to whether the USB connector can handle 2.5A is a matter for find out the specs of the connector.

Unfortunately only foundation can answer question on PCB trace widths, it may well be an inner layer then it
is dependant on the via paths you would be using.
Just another techie on the net - For GPIO boards see http:///www.facebook.com/pcservicesreading
or http://www.pcserviceselectronics.co.uk/pi/

Nakedible
Posts: 2
Joined: Mon Oct 01, 2012 11:54 am

Re: Maximum power input via the 26-pin GPIO header on Rev 2.

Tue Oct 02, 2012 9:05 am

Does the foundation answer questions like this here? Or is there another way to try and get a reply?

There is a commercial project possibility involved, too, so it would be nice to get a definitive answer.

simplesi
Posts: 2327
Joined: Fri Feb 24, 2012 6:19 pm
Location: Euxton, Lancashire, UK
Contact: Website

Re: Maximum power input via the 26-pin GPIO header on Rev 2.

Tue Oct 02, 2012 9:08 am

If there is a commercial product, then I'd recommend just testing one to 200% of what your project needs and seeing if your RPi survives as you'd only be down £30:)

Simon
Seeking help with Scratch and I/O stuff for Primary age children
http://cymplecy.wordpress.com/ @cymplecy on twitter

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