> On Sat, 17 Jun 2000, Greg Hastings wrote:
>
> > The PIC 16F84 spec says it can
> >
> > sink 25mA max
> > and
> > source 20mA max
> >
> > What is the difference between the two?
>
> Sink:
> Current flows into the PIC from an external source...
> ------
> PIC  |--/\/\/\------ GND
> ------
>
> Source:
> Current flows out from the PIC to an external load...
> ------
> PIC  |--/\/\/\------ +V
> ------
>
> Somebody please tell me I didn't get that bass-ackwards, it's been a long
> day.
>
> Dale

Sorry Dale, it's bass-ackwards. Your description is perfect but your
diagrams are muxed ip. Swap GND and +V and it's right. Good
effort though for a long day. Just to make sure:

Sinking current is when you connect one end of your load to +V
and the PIC pulls the other end to ground (current flows into PIC).

Sourcing current is when you connect one end of your load to GND
and the PIC drives the other end to +Vdd (current flows out of PIC).


Brent Brown
Electronic Design Solutions
16 English Street
Hamilton, New Zealand
Ph/fax: +64 7 849 0069
Mobile: 025 334 069
eMail:  brent.brown@clear.net.nz