74HC Series Logic – Texas Instruments SN74HC74N, The Texas Instruments 74HC74N Dual D-type flip-flop with preset and CLR is available in a SO-14 package. It has full function and pin compatibility with LSTTL family and most types of the CMOS-4000 family. It features very short switching times and a fan out of 10 LSTTL loads. Texas Instruments SN74HC74N Logic Dual D Type Flip Flop DIP14