SN74LVC1G08-Q1: Difference between SN74LVC1G08IDKRQ1 and SN74LVC1G08QDCKRQ1?

"Q" indicates a wider temperature range than "I".

The lead finish is different because these devices can come from different assembly sites, but this is not something that affects the electrical characteristics. (If you want to avoid the Sn lead finish, use 74LVC1G08QDCKRQ1G4.)

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