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PIC18F2550 current source total?

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Garyl

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Hey
The PIC18F2550 datasheet reads:
"High-Current Sink/Source: 25 mA/25 mA"
So I can connect, for example three pins to 20mA LEDs? Or six pins?
I mean, is there any "global current limit" for sourcing or sinking?

Also... I want to drive several 20mA LEDs with PIC18F2550, should I use sinking (LED between pin and VCC) or sourcing (LED between pin and GND)?
 

Hey
The PIC18F2550 datasheet reads:
"High-Current Sink/Source: 25 mA/25 mA"
So I can connect, for example three pins to 20mA LEDs? Or six pins?
I mean, is there any "global current limit" for sourcing or sinking?

Also... I want to drive several 20mA LEDs with PIC18F2550, should I use sinking (LED between pin and VCC) or sourcing (LED between pin and GND)?

Datasheet section 28.0 states that maximum current sunk or sourced by all ports is 200mA, so max 10 LEDs at 20mA if no other port pins used. This is absolute max value, probably best not to run at max all the time, but 6 LEDs should be perfectly good.
Sink or source - both are fine.
I find my head copes best with source, so that a '1' output lights the LED. (sink requires a '0' output to light the LED). This is not a design choice, simply personal preference where there is an equal choice available.
 
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    Garyl

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