You've passed prototype validation, compliance, qualification and have been running hundreds of thousands of units a month...until now.
ESD issues have suddenly crept up and there's a twice-daily engineering status meeting with the manufacturing managers. The cc: list on the status update continues to grow.
What. Is. The. Root. Cause?!
This happens to the best designs, but from this point a cool head, methodical approach and a little luck are required.
While a lot of time and effort can be spent chasing bad assumptions and dead-ends, many of these can be eliminated with an across-the-board (literally) ESD Susceptibility scan.
- Has something changed on the board assembly?
- Does a sample scan of the system show any new vulnerabilities which were not recorded on the prototype or early production runs??
- Has a particular component changed?
- Substitutions and cost reductions without a PCN can be eliminated from the list of suspects as above.
- Hard failures are self evident, but soft errors are not.
- Hard failures cause damage that can be analyzed at the chip level. Soft failures leave few if any breadcrumbs.