I think the datasheet of the STM32L041F6 states incorrect package information on page 105:
These values are not correct as pin pitch can never be 3.5mm.
Where should I notify this error?
It should suffice to do it here. Usually the ST staff pays attention.
The drawing for the UFQFPN28 package two pages further states more plausible values for those measures.
I confirm that values provided for the parameters E, E2, e & L are wrong in the table "UFQFPN32 - 32-pin, 5x5 mm, 0.5 mm pitch ultra thin fine pitch quad flat package mechanical data" of the STM32L041F6 (and STM32L031) datasheets.
Waiting for the corrected versions of the datasheets, you may refer to STM32L051 datasheet.
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