Kenneth Lumia wrote:
>> I think this chip is almost a year old, and still new bugs arrive,
>> when will it stop? 
>> Or should we only use components older than say 2 years ?
>> Is this common for uChip products ?
>> What other experiences are there with new uChip products.
>>
>>     
>
> Welcome to engineering!  Designing with "bleeding edge" 
> parts is always fun.  One time, I had the misfortune of using 
> a high-speed ram chip that had a pattern sensitivity problem.  
> It was a brand new part from the vendor.  They were rather 
> unhappy when I sent in the scope traces and failed parts.  
> Shut their production down for over 5 months!   
>
> On the other hand, older parts can also have problems.  
> Vendors occasionally do "die shrinks" as technology 
> progresses to get more parts out of a wafer and hence 
> lower cost.  This of course is a new part that pretends to 
> be an old part.  
>   
I had a product that suddenly began failing when new "HC" parts had been 
dieshrunk.
The new devices were incredibly hot and very sensitive to noise. I had 
to redesign
the PCB and add more bypass caps and elmininate a timing race I didn't 
even know was
therre. The product had been made for 6 years without a single failure 
before that. Go
figure.

--Bob

> Then there are parts that have been around for a long time 
> and do to some process deviation during manufacture 
> non-apparent problems occur.   I won't bore you with details.
>
> I've found that the best overall strategy is to attempt to avoid 
> new parts if possible, and always create designs that 
> have significant margin over the minimum published 
> specification (at least as to what is practical).  This 
> way, even if parts don't meet spec, your designs have 
> a better chance of still working correctly.  
>
> For the software/firmware side,  downloadable or 
> bootloadable options are a really good idea.
>
>
> Ken
> _______________________________________
> "Well that never happened in any of the simulations"
> klumia@adelphia.net
>
>
>
>   

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