TMUX721x CMOS Switches Texas Instruments TMUX721x CMOS Switches are complementary metal-oxide semiconductor (CMOS) switches with four independently selectable 1:1, single-pole, single-throw (SPST) switch channels. The devices work with a single supply (4.5V to 44V), dual supplies (±4.5V to ±22V), or asymmetric supplies (such as VDD = 12V, VSS = –5V). The TMUX721x supports bidirectional analog and digital signals on the source (Sx) and drain (Dx) pins ranging from VSS to VDD.