SN74ALS652A SN74ALS620A SN74ALS621A SN74ALS621A-1 SN74ALS623A SN74ALS638A SN74ALS639A SN74ALS640B SN74ALS640B-1 SN74ALS641A SN74ALS641A-1 SN74ALS642A-1 SN74ALS645A SN74ALS646A SN74ALS648 SN74ALS648A SN74ALS653 SN74ALS654 SN74ALS666 SN74ALS667 SN74ALS677A SN74ALS688