The ADG1401/ADG1402 contain a single-pole/single-throw (SPST) switch. Figure 1 shows that with a logic input of 1, the switch of the ADG1401 is closed and that of the ADG1402 is open. Each switch conducts equally well in both directions when on and has an input signal range that extends to the supplies. In the off condition, signal levels up to the supplies are blocked.