Trouble with the last batch of ST62T28C6 (PHL 99 611)

esd · ‎2008-03-22

Posted on March 22, 2008 at 18:04

esd · ‎2007-09-25

Posted on September 25, 2007 at 23:16

We are experiencing trouble with our last batch of ST62T28C microcontrollers. We are getting a high failure rate. Approximately 5%. The devices seem to be VERY temperature sensitive. Cold = Fail, Warm = OK. Has anyone else had the same trouble? Is this just poor quality control on the last batch of superseded microcontrollers. Or has some parameter changed that I am NOT aware of? Please Help.

NB We have run many thousands of these devices. The problem is in the last batch

:-[

geoff3 · ‎2007-10-17

Posted on October 17, 2007 at 10:12

I think we got a dud batch as well. I initially suspected the supplier had procured the items from his customers - but after reading this article, I'm leaning towards the thought that it could be the ICs themselves. :-? We had a high failure during burning (I'd say as much as 30%) - and some that burnt failed - intermittently in the field. And it was definitely only from the last batch we obtained. These ICs were DIP package, so we're going SMD for the last batch of these devices.

esd · ‎2007-10-29

Posted on October 29, 2007 at 20:35

Hi Geoff1

Donâ€™t bother with the surface mount devices. That is the package we are using. We have had production and field failures as well. Low temperature seems to show the fault better although this is not conclusive. We now place each batch in a fridge to drop the temperature in order to try and catch the faulty devices. There is not a lot else we can do to test the devices. We have sent a handful of faulty chips to ST for testing.

We bought a large quantity to make our product last while we develop a replacement. This faulty batch has changed this plan. I wonder if anyone else has had troubles as well.

:(

good2dog · ‎2008-03-22

Posted on March 22, 2008 at 18:04

hi Barry_R & geoff1

if you still have such a failed part and you can send few of it in italy, i may run some rom laboratory test at low_high temperature.

regards