Pin max current - short duration?

[mister_e]

that's the real beauty to build some home-brew prototype before sending the Gerber file to the PCB shop

[duncan303]

Hi,

This relates to something I have been thinking about for while, and how i might be able to contribute back.

I too place through vias in tracks simply for the purpose of amending a design I will also place a Tee configuration of smd resistor pads especially on pins that I am not using, alowing me to tie down/up. However carefull I am to try and finalise a layout there will inevitably be a better way to execute a task, a constant cyclic routine of firmware vs components re-evaluation.

I recall a post recently, "why don't people use breadboards"....... well ,for me, breadboards are great for quiick evaluation of simple circiuts but inevitably they get crowded and the connections can be unreliable. The point for me is that the bench has far too may loose cables, clips, probes, blue tack. Actually my breadboard is handy because I can clamp it overhanging the bench and increase my working space...... and then I can hang even more cables over it when I'm not using it. The breadboard is a great tool, but can be given looks of derision when off the bench, it is also worth noting that some people can be a little scared of an electronics especially when you have invented something marvelous for the home environment.
"whats that thing doing, dear? are you sure its safe"!..........

anyway my point is that I have had in mind to create a panelised pcb layout for most of the pin count PICS and provide these as gerbers or jpgs for people to either have made up locally, or to be created with the most basic minimal equipment for example; exposure by the sun, increased footprint pad length (make smd easier with basic soldering iron),

from memory was it not sparkfun who started me on reflow with a domestic frying pan



OR are there just too many differrent permutations of the way people use PICS to make it worth while..

Or just put your breadboard in box!! simple solutions always best

Discuss

ps this should probably be in shematics

[Acetronics2]

from the Midrange Databook $30.5

Example Absolute Maximum Ratings†
Ambient temperature under bias........................................................................... . -55 to +125°C
Storage temperature .......................................................................................... -65°C to +150°C
Voltage on any pin with respect to VSS (except VDD, MCLR, and RA4)..... -0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ....................................................................... -0.3 to +7.5V
Voltage on MCLR with respect to VSS (2) ...................................................................... 0 to +14V
Voltage on RA4 with respect to Vss .............................................................................. 0 to +14V
Total power dissipation (1) .................................................................................................... 1.0W
Maximum current out of VSS pin ...................................................................................... 300 mA
Maximum current into VDD pin ......................................................................................... 250 mA
Input clamp current, IIK (VI < 0 or VI > VDD).................................................................... ± 20 mA
Output clamp current, IOK (VO < 0 or VO > VDD) ............................................................. ± 20 mA
Maximum output current sunk by any I/O pin..................................................................... 25 mA
Maximum output current sourced by any I/O pin ............................................................... 25 mA
Maximum current sunk by PORTA, PORTB, and PORTE (combined)............................. 200 mA
Maximum current sourced by PORTA, PORTB, and PORTE (combined) ....................... 200 mA
Maximum current sunk by PORTC and PORTD (combined) ........................................... 200 mA
Maximum current sourced by PORTC and PORTD (combined)...................................... 200 mA
Maximum current sourced by PORTC and PORTD (combined)...................................... 200 mA
Maximum current sourced by PORTF and PORTG (combined) ...................................... 100 mA
Maximum current sourced by PORTF and PORTG (combined) ...................................... 100 mA

just need to be read ...

ALSO WRITTEN: SEE PARTICULAR DATASHEETS ...

Means parallelling outputs ( or inputs ... why not ? ) is allowed ... You're right, Steve !!!
Alain