The ADS816x is comprised of five modules: the converter (SAR ADC), multiplexer (MUX), the reference module, the enhanced-SPI interface, and the low-dropout regulator (LDO); see the Functional Block Diagram section.
The LDO module is powered by the AVDD supply, and generates the bias voltage for the internal circuit blocks of the device. The reference buffer drives the capacitive switching load present at the reference pins during the conversion process. The multiplexer selects among eight analog input channels as the input for the converter module. The converter module samples and converts the analog input into an equivalent digital output code. The enhanced-SPI interface module facilitates communication and data transfer between the device and the host controller.