PIC temperature, when is it too hot

[HenrikOlsson]

provided that the current is spread over a number of i/o pins and that no individual pin is overloaded

Yes, the voltage drop across the switch increases as the current goes up. That's why I was being conservative with the 1V voltage drop.
But really, as long as the voltage drop isn't MORE than 1V it wouldn't matter (from a power dissipation standpoint) if the 110mA exits the device thru one pin or 25. Of course, you'll likely destroy the pin but it's still 110mW dissipated.

Point is, 600mW isn't being dissipated in the PIC. Keep the current to within specification and you'll be fine. No heatsinks, fans or watercooling needed. If you think you need that (chip is burning hot) something is wrong.

BTW: Am I the only one not being able to edit my posts? All I get is a blank "edit box" as if I was making a new post.
EDIT: Hmmm, not this time, on this machine. Weird.

[Ioannis]

What I was thinking... Henrik is right as all that current is flowing out of the PIC and not to ground.

So indeed, the only power loss is the voltage drop on the output buffer times the specific pin current.

Sorry about that, guess it was too late at night to post anything...!

Ioannis

[richard]

BTW: Am I the only one not being able to edit my posts? All I get is a blank "edit box" as if I was making a new post.
EDIT: Hmmm, not this time, on this machine. Weird.

not anymore

i cannot edit my posts either

[Ioannis]

Maybe clearing cache, or a different browser resolves the problem?

Ioannis

[richard]

Maybe clearing cache, or a different browser resolves the problem?

tried all that. problem still comes and goes, seemingly at random

[Ioannis]

Then only boss can check that...

Ioannis

[Ioannis]

It got me too... I really cannot understand what is going on.

It showed me an empty text box. Was it the same with you too?

Ioannis

[richard]

That's it, an empty box

[richard]

That's it, an empty box

But not this time, but reason for edit box has gone missing


Third try reason box is back