I have a question about AD590 FLATPACK from our customer.
The customer wants to know what kind of material is used for the surface plate, which is the upper side of figure 25 of datasheet. ( "the surface plate" means the hatched part of attached drawing )
Even though the datasheet said this package is "Ceramic Flat Package", this part looks like to have a window, we were not sure that this part is ceramic too.
Is this part ceramic too ?