text: differences ? what is the difference between  cd74hc4067  and  cd4067 not to sure on the 74h vs just 4000 series. this is being used to multiplex multiple switches to a micro controller. both are cmos devices. cd4067 is slower device compared with 74hc4067. hc stands for high speed cmos. cd4067 has maximum on/off time of 190/130 ns where as 74hc4067 has maximum on/off time of 64/62 ns. cd4067 is older device in comparison with 74hc4067.