Many CMOS switches are unable to support a voltage at the input without a valid supply voltage present, otherwise the voltage will be coupled from input to output and could damage downstream devices or impact power-sequencing. The TMUX13xx circuitry can handle an input signal present without a supply voltage while minimizing power transfer from the input to output of the switch. By limiting the output voltage coupling to 400 mV the TMUX1308 and TMUX1309 help reduce the chance of conduction through any downstream ESD diodes.