TMUX1237 SPDT General Purpose Switch Texas Instruments TMUX1237 SPDT General Purpose Switch is a general-purpose 2:1, single-pole double-throw (SPDT), switch that supports a wide operating range of 1.08V to 5.5V. The device supports bidirectional analog and digital signals on the source (Sx) and drain (D) pins ranging from GND to VDD. The state of the select pin (SEL) controls which of the two sources pins are connected to the drain pin. Additionally, the TMUX1237 has a low supply current of 7nA, which enables the device to be used in a host of handheld or low power applications.