Vishay General Semiconductor offers a diverse array of general discrete semiconductor products, including 1N4148W-E3-08. Recently there has been confusion surrounding this part and its most recent product change notice - parts with date/lot codes dating from after the PCN are showing the same top markings as parts from before the PCN. Is this an error?
The current product marking for this device is AH, but some examples exist with the A2 marking that was once correct, even after the PCN. This is because the product was manufactured before the PCN cutoff date, using the prior method of manufacture, but only reeled and sold after the PCN went out. Vishay does not consider this a manufacturing error, and the products should generally still be fine.