Hello everyone,
a few weeks ago I ordered a few
2N6422 BJTs from DigiKey. They were the last ones available, offered through their "marketplace" program directly from the manufacturer, Solid State.
Since they were unavailable everywhere else (unless one wants to order at least 100 from Microchip at $27 each
), I figured that they must be some new old stock gathering dust in a corner of the manufacturer's warehouse.
I placed the order for the available stock on May 2nd and the package arrived today (courtesy of the Italian customs
).
Well, take a look at the date codes:
(yes, one is upside down, all the electrons are gonna fall out
)
2318, the same week when I placed the order!
They were listed as available before I placed my order, and now they are not any longer. So I highly doubt that the folks at Solid State fabricated a batch of 2N6422s dies just for me. But at least the date code printing must have happened after I placed my order.
Perhaps the manufacturer had bare dies in storage and packaged them into TO-66 packages when I placed the order? In that case the date code would represent the time that the silicon was packaged, not when the silicon was fabricated.
So, my question is: what do date codes indicate exactly? I was under the impression that they indicated when the actual silicon was produced, but perhaps they only indicate when the last step in the manufacturing process is carried out?
Just a note in case someone from Solid State happens to read this: I'm not complaining, at all. I'm just curious
Best regards,
Andrea