There are two VSS & two VDD in PIC16F877A.

I’m making a PCB for 877A project. What I want to know is they internally connected or not?

Otherwise I have to draw another two PCB tracks from PORTB side VSS & VDD to PORTA side VSS to VDD.

 

They are connected internally, but still, hook up BOTH sets of pins. Absolutely.

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I thought what I'd do was I'd pretend I was one of those deaf-mutes.

 

OMG if they are internally connected why I need to tie them again from outside?

 

It keeps old man Murphy from knocking on your door while you're working on your project.

 

Nothing stops Murphy from knocking. What matters is to keep his old but from entering. Taking care of the low hanging fruits first puts up a get front.

P.S. Many other chips have multiple Vdd and Vss, I using only one of each because I stopped Murphy from even getting out the bed baby.

 

Thats what I need you have already tried with one VSS & one VDD.

Thanks for that then I can reduce my PCB space too.

 

Don't do it, bad plan. The internal interconnects are very tiny wires, to be reliable you need to hook up both VSS & VDD pins. Of course you didn't skimp on the decoupling caps...

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Bill
Smart Kits build Smart People
http://www.blueroomelectronics.com

 

I concur, connect ALL Vdd and Vss pins - they aren't there for no reason!.

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PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

you just use any one VDD and VSS only enough.

 

Only if you like to make things that won't be reliable!.

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PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

Penny wise and pound foolish.

 

The common culprit is the saying "I have tried that and it works".

Some people jumped from a height of 30 ft and end up unhurt. It works too.

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L.Chung

 

You could have soldered jumpers to bypass your PCB routing problem ten times over in the time it took to post this question.

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I thought what I'd do was I'd pretend I was one of those deaf-mutes.

 

Hi Guys finally I thought why I standing from one leg Better stand from both.
I coupled PCB tracks from both sides VDD & VSS.

Thanks for your ideas.

 

Has not going to post this but this is for you


Anybody want to pic a multiple Vdd/Vss PIC and run a reliability test based on using only 1 Vdd and Vss? Draw a matrix of usages and results, then return with hard statistics that can be varified by third party using said matrix. if not, anything else is vapor.



Back to actually doing something I return.