The ADG1438/ADG1439 use a versatile 3-wire serial interface that operates at clock rates of up to 50 MHz and is compatible with standard SPI, QSPITM, MICROWIRETM, and DSP interface standards. The output of the shift register, SDO, enables a number of the ADG1438/ADG1439 parts to be daisy-chained. On power-up, the internal shift register contains all zeros, and all switches are in the off state. Each switch conducts equally well in both directions when on, making these parts suitable for both multiplexing and demultiplexing applications. Because each switch is turned on or off by a separate bit, these parts can also be configured as a type of switch array, where any, all, or none of the eight switches can be closed at any time. The input signal range extends to the supply rails. All channels exhibit break-before-make switching action, preventing momentary shorting when switching channels.