Re: [Gumstix-users] How much current can GPIO pins source?

[Doug S. <do...@pr...>]

Chris,

You should take a look at
PXA255 Processor Electrical, Mechanical, and Thermal Specification
http://www.intel.com/design/pca/products/pxa255/techdocs.htm

Section 4.4 Targeted DC Specifications
Table 10 shows the specs for IO pins

You can connect wires to breakout-gs, thin wire hehe. Those holes
will fit 50 mil (1.27 mm)pin headers. They are exactly half the
size of the regular 0.1" spaced headers on most boards, like this:

http://www.gradconn.com/1.27mm_board_to_board_connectors.html

The GPIOs are not intended to sink or source much current.
Looks like 10mA is okay but on the edge, if you need to source
more current you'll need to trigger a circuit with the output
from the pins.

   -- Doug




Chris Dew wrote:
> I haven't been involved with electronics for 10 years now...
> 
> How much current can GPIO pins on the breakout-gs board source.  I have 
> lit LEDs in series with resistors, which draw 10mA, and the gumstix did 
> not break.  I would like to make them brighter, without frying the 
> gumstix. What is the maximum current I am able to draw?
> 
> How do I connect wires to the breakout board?  The holes are too small 
> to push wires through, let alone trying to solder them.  Is there a 
> connector available (UK)?
> 
> Can I connect the GPIO pins directly to GND when using them as an 
> input?  I have previously limited them by resistor to 10mA also.  This 
> is enough current to make the input readable.  Is an inline resistor 
> completely unnecessary when using a GPIO pin as in input?
> 
> Regards,
> 
> Chris.