MODIFIED: Is it advisable to group two (or more) GPIO out pin to obtain more mA?

Started by flavigny, October 13, 2012, 07:33:20 AM

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I have to drive external load at 3V, 24 mA.
In the design, I will insert an Uln2803 driver.
BTW, is it possible to simply use more than one GPIO pin ?

I dream about this schema:
[modified to limit current on EACH pin.]
    GPIOx------>|----(resistor 470 Ohms)----------+
    GPIOy------>|----(resistor 470 Ohms)----------+-(load)--Gnd
    GPIOz------>|----(resistor 470 Ohms)----------+

so, current from each pin is approximatively limited to 7mA.

Does anyone could confirm ?

Post-Scriptum: According to the answer below from Olimex, I read Chapter 37 and table 2.8 in: . At this time I have not found the maximum power available.


generally yes, just look in the user manual or datasheet what is the max current which could be sourced from one port group.