The TechForum Cross Reference category is for parts that Digi-Key does not sell or parts that have gone obsolete. Our Engineers and Techs have reviewed the specifications for these parts and made a recommendation for a replacement. Please review the suggested part to ensure it will work for your application.
BC81740MTF (Digi-Key Number- BC81740MTFCT-ND or BC81740MTFTR-ND) is an ON Semiconductor that has gone obsolete, however there are viable alternatives available.
The part that currently looks best positioned to use as a replacement is BC817-40-TP (Digi-Key Number- BC817-40-TPMSCT-ND or BC817-40-TPMSTR-ND). It appears to be a good drop-in replacement, though I recommend reviewing the specifications to verify that it works for your application.