Pi accessories from Farnell ... USB chargers?

Arggghh!!!!

Please check the things that John has pointed out.  Unless the leads are a complete disaster (easily corrected), that power supply is beneath contempt.  2A USB?  Hahahahahahaha

This Pi experience with alleged "USB-spec" chargers has been amazingly eye-opening.  It points out vividly how manufacturers treat specs with total disdain in the search for profit.

Morgaine.

@ Morgaine,

If it comes to an RPi board change it would seem to me that the best bet was either change over to nominal 12V in (possibly 9)  and use a switcher down to 5V on board or if compatibility is essential stick with the micro USB and nominal 5V in and fit a boost switcher on the RPi to take it up to 5V.

For my money the boost solution is the second best from an engineering point of view but probably the best overall solution since so many people are already locked into the micro USB power connector idea.

It won't be quick - board re-spin, prototype, test (EMC this time ?), feed into production ........ six weeks ?

Short term someone could pick up the pieces with special power supply - talking of which has anyone tried one of the supplies being offered specifically for the RPi ?

Michael Kellett

Will have a looksee over it again tonight when I get home, To be fair to the cable, it was a no-longer-used SE USB data cable, so probably not the biggest bit of cable around, or the best. Just what I happened to have at the time!

Hi all,

Just seen this - anecdotally, we've been using this poweredpowered USB hub (as expansion ports and power supply) at exhibitions to demo the Raspberry Pi and it has worked really well.

We've also been using smart-phone chargers (in particular for BlackBerry) which have also been more than capable.

To be fair we've probably not been pushing the Pi to its limits though. The heavy power consumption really seems to come from driving the GPU to its limits, so I expect it would be in these cases where you need to pay particular attention to the current delivery of whatever PSU you're using.

Hope this helps, again, it's only our own experience from exhibitions and demonstrations so I can't speak for all cases.

Joe Alderson - Technical Marketing Engineer (Farnell element14).

edit - made the product link work.

@Joe,

The data sheet for that part says it is a Bus powered hub but the Farnell listing says it comes with a UK plug. Does it have an external supply and what is it's spec ?

Michael Kellett

Hi Michael,

Looks to me like it's a mistake on the datasheet - the ones I've picked up to use with it have all come with a UK plug and external supply included (says on the description that it's powered so I guess that the datasheet wasn't updated). Will check up on the spec for you!

Thanks,

Joe

Looks like some manufacturers are being creative with the word "powered", and putting "host-powered" and "USB-powered" into the category of "powered hubs" as a marketing bullet point.  <sigh>

Yeah, looks like you're right - I've just sifted through the list of USB hubs. These are the ones that I've found with an external mains connection that isn't just a USB one:

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N.B. there are probably more but I didn't think there was much need for showing USB hubs > 13 ports , also there will be European plug variants for some of the hubs.

The interesting thing is that this setup allows for the next picture.....

Please ignore the mess, and the spider.... and the snakes.... and the complete lack of anything even vaguly like cable routing......

That is a RPi running off a USB hub without throwing a paddy (also had it running off the power supply that I was less than generous about a couple of days ago)