The AD7689 is an 8-channel 16-bit, charge redistribution successive approximation register (SAR), analog-to-digital converter (ADC) that operates from a single power supply, VDD. The AD7689 contains all of the components for use in a multichannel, low power, data acquisition system including: a true 16bit SAR ADC with no missing codes; an 8-channel, low crosstalk multiplexer useful for configuring the inputs as single ended (with or without ground sense), differential or bipolar; an internal low drift reference (selectable 2.5V or 4.096V) and buffer; a temperature sensor; a selectable 1-pole filter; and a sequencer useful when channels are continuously scanned in order. The AD7689 uses a simple SPI interface for writing to the configuration register and receiving conversion results. The SPI interface uses a separate supply, VIO, which is set to the host logic level.