There's no substitute for process.  Where I work, the rule is that 2 sets of 
eyes check every schematic symbol.  Just because the symbol has a pin labeled 
reset and it's on pin 1 doesn't mean that the datasheet agrees with the symbol.

Also, two sets of eyes are required to check every package symbol.  Pin 1 has 
to be where pin 1 of the drawing says it's supposed to be.  And, of course, 
every dimension of the package has to match the drawing.

The problem I see, because I'm (lots of us are) doing home-brew designs outside 
of work, is that there's no second set of eyes to check these things. If you're 
using this tool at work, then have someone take the datasheet and hi-lite every 
pin in both the datasheet and the schematic symbol.  Likewise for the footprint 
symbol.  Then, file these away with the design documentation so there's no 
second-guessing by management later when there's an error.  You could do this 
at home as well but whenever the same set of eyes does the making and checking, 
there's a much greater chance of an error sneaking through.

Of course, when the symbol and package have 1152 pins, everyone runs screaming 
the other way when I show up in their office to request a symbol check.

It's discipline and process that separates the amateurs from the pro's.  So, 
develop a process, even if you're on your own, and follow it rigorously.

--- In kicad-users@yahoogroups.com, "Stephrac74" <stephra...@...> wrote:
>
> Hi guys,
> 
>  
> 
> I would like to share with you my very bad experience in order to help you
> to avoid becoming completely depressed as I am now…
> 
>  
> 
> I've been working about 50 hours on a PCB using Kicad and the libraries
> found on the soundforge. I've a TFQP microcontroller in my design and used
> the module found in microchip-2 library called TQFP64 ! I've not checked
> before drawing the PCB that the module was ok…. And what a mistake !
> 
>  
> 
> The module is wrong, dimensions are not correct making the component
> impossible to mount and solder ! I can of course correct this by changing
> the module, but using Kicad this means erasing all the wires connected there
> and restart most of my design (very compact). I think about 20h more to
> spend on this PCB…
> 
> That is absolutely dramatic for a professional use as spending 70h on a such
> basic PCB with around 100 components !
> 
>  
> 
> So my best advice is to redesign all your modules and not spend one minute
> using the libs you can find in Kicad or on the web. There are so many errors
> that you discover all along your design (silkcreens, wrong dimensions, …)
> making finally a massive waste of time. Of course, If I knew that before I
> would have redesigned all the components and created my own libs…
> 
>  
> 
> Hoping it will prevent some other people to face what I'm facing now ! 
> 
>  
> 
>  
> 
> Best
> 
> Stephane
>


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