OnOff shim maximum current, stacked header, Pibow coupe?


#1

Searching the product page for the OnOff shim, and this forum, I couldn’t find answers to my questions, so hopefully someone here can answer them:

  1. What is the maximum current the OnOff shim can handle? Does it allow a Pi 3B with official 7" Touch LCD? Does it handle 2.5A?

  2. When using a stacked GPIO header, but not the extra tall one, with 10/11mm headers, can I use the OnOff shim with such a header, place a pHAT or HAT on top with its own female block, and does this still fit with a Pibow coupé casing? (the pictures suggest that the Pibow coupé works, but I want to be sure with using an extension header…)


#2

The OnOff shim will handle 2.5A yes. It’s designed with the official Pi power supply in mind.

I’m not sure about the stacked GPIO header- my brain is mushy today and I’m having trouble visualising what you describe :D (and, of course, have none of the above to hand to test it :D)


#3

What if I have a power supply of maximum 3A?
Can I expect to fry it or any other side effects?


#4

You aren’t advised to use 3A power supplies with a pi. I don’t know whether it would work. If you try it you may be subject to magic blue smoke though!


#5

Hi

Why?

The Pi will only draw what current it requires from the power supply. You could use a 5A supply so long as it’s only giving 5v.

Cheers

Paul


#6

supports up to 2.5A power supply

is what it says on the product page and to be honest I am more or less talking from that.


#7

Hi

Ah that’s different to what you put in your post which stated “you arn’t advised to use a 3A power supply with a Pi”.

You can use a 3A supply and there is no reason why you shouldn’t, however if you are powering the Pi via the on/off shim then it is only rated at 2.5A. Should the pi draw more than 2.5A due to any added peripherals then you could have an issue.

Cheers

Paul