| ??? 11/19/07 15:56 Read: times |
#147193 - I believe you! Responding to: ???'s previous message |
Richard said:
I work with high end telecomms equipment, upto 10GB/s and we have had several issues with noise and equipment failures, all of which can be traced back to the manufacturers recomendations. We have even had them admit that they chose a particular layout just because a competitor did.
One case involved a 200MHz processor from a very well known company, that would not work reliably on some units if the temperature was low (we need to work @ -5C, they were failing @ +20C!). The cause - Layout and decoupling on PLL supply pins. I believe you, sometimes manufacturers are real bad. We had an comparable problem with Analog Devices some years ago. From one lot to the next we observed a huge rise of charge injection, but the manufacturer denied that something was changed. Years later we found in an updated datasheet, that they changed the die layout in order to "improve" something... Kai |
