TC74VHC21FT-ELK(M) TC74VHC21FTELM TC74VHC221A TC74VHC221AF TC74VHC221AF(E,K,F TC74VHC221AF(ELF) TC74VHC221AF(K.F) TC74VHC221AFK TC74VHC221AFK(EL,K TC74VHC221AFN