Mass production issue. ( the download firmware auto changed ? )

[Boki]

Hi All,

I have a couple of mass production issues, please advice:

Issue A.
Step 1. The product was pass the ATE test, when it go through the
production line.
Step 2. Randomly choose fewer samples to do hand test.
Step 3. Some samples fail, compare the firmware, it is different to
correct firmware. ( but it pass the firmware check in ATE station! @@~)


Issue B.
When test by hand and found a fail unit, the firmware is the same (
correct ), but behavior is different ( fail ) ( also pass the ATE test
at beginning).
In this case, we saw different EE behavior ( a power pin has different
behavior, it should no voltage at this moment, but it has), but after
re-download the firmware, the problem gone!


Please kindly share with your experience or any comments.

Thank you very much!
Best regards,
Boki.

 

[Spehro Pefhany]

Hi All,

I have a couple of mass production issues, please advice:

Issue A.
Step 1. The product was pass the ATE test, when it go through the
production line.
Step 2. Randomly choose fewer samples to do hand test.
Step 3. Some samples fail, compare the firmware, it is different to
correct firmware. ( but it pass the firmware check in ATE station! @@~)


Issue B.
When test by hand and found a fail unit, the firmware is the same (
correct ), but behavior is different ( fail ) ( also pass the ATE test
at beginning).
In this case, we saw different EE behavior ( a power pin has different
behavior, it should no voltage at this moment, but it has), but after
re-download the firmware, the problem gone!


Please kindly share with your experience or any comments.

Thank you very much!
Best regards,
Boki.

Both issues could be caused by a crappy supply supervisory circuit.

 

[Frithiof Andreas Jensen]

Please kindly share with your experience or any comments.

Maybe your programmer is broken or out of date with the version(s) of chip you
are programming?

I had some fun & games with PIC's that would program perfectly then fail on the
job - a delve through the runes of the darker application notes revealed that
the programming procedure was indeed changed between two steppings of the same
chip. Upgrading the programmer software fixed this.

 

[Charlie Edmondson]

Maybe your programmer is broken or out of date with the version(s) of chip you
are programming?

I had some fun & games with PIC's that would program perfectly then fail on the
job - a delve through the runes of the darker application notes revealed that
the programming procedure was indeed changed between two steppings of the same
chip. Upgrading the programmer software fixed this.

Or, you are using a commercial module that has a default settings mode.
You change the mode during the initial programming, but later,
something is resetting the module back to its default settings...

Charlie

 

[Joerg]

Both issues could be caused by a crappy supply supervisory circuit.

Yep, that sure sounds like a dirty reset.