Greetings Experts!
Unlike Point #2, Point #3 didn’t states that the structure which is in intimate contact with ESD Sensitive Devices has to provide ESD Shielding.
Which means can I conclude that a material which makes an intimate contact with an ESD Sensitive Device not necessarily need to be shielding??
Secondly, is it acceptable if I packed my FG (PCBAs) into tote box and then enclose the whole tote box with a big Static Shielding Bag?
Please advise.
Warm Regards,
Logan
Logan,
I wouldn’t conclude that a material which makes intimate contact with an ESD Sensitive Device does not need to have shielding. The better way to read this is that discharge shielding is required in either case where the packaging makes or doesn’t make intimate contact with the ESDS item.
Yes, if your PCBAs are in a conductive or dissipative tote box within a bigger static shielded bag, this should meet the packaging requirements of ANSI/ESD S20.20 for transport outside an EPA
There are many ways to create a package that will be discharge shielding. The basic rule is the place the ESD sensitive item next to a high resistance layer than a low resistance layer around that. For example, if there are high resistance foam in a low resistance tote (plastic or cardboard) that could be considered a dishcharge shielding package.
If there are air gap between the ESD sensitive item and the outer package, a “dissipitive” thermaform package can be considered a discharge shielding package.
If there are air gaps in any package, a dissipitive or conductive container can be considered a dischage shielding package.
Static shielding bag have a high resistance inner layer with a conductive layer around that. That is how they achive a discharge shield.
