16-Bit, 100-kSPS, 1-Ch SAR ADC with programmable (±12/±10/±6/±5/±2.5V) input ranges on +5V supply

The ADS8681, ADS8685, and ADS8689

belong to a family of integrated data acquisition system based on a successive

approximation (SAR) analog-to-digital converter (ADC). The devices feature a

high-speed, high-precision SAR ADC, integrated analog front-end (AFE) input driver

circuit, overvoltage protection circuit up to ±20 V, and an on-chip 4.096-V

reference with extremely low temperature drift.

The devices operate on a single 5-V

analog supply, but support true bipolar input ranges of ±12.288 V, ±6.144 V,

±10.24 V, ±5.12 V, and ±2.56 V, as well as unipolar input ranges of

0 V to 12.288 V, 0 V to 10.24 V, 0 V to 6.144 V, and

0 V to 5.12 V. The gain and offset errors are accurately trimmed within the

specified values for each input range to ensure high dc precision. The input range

selection is done by software programming of the device internal registers. The

devices offer a high resistive input impedance (≥ 1 MΩ) irrespective of the selected

input range.

The multiSPI digital interface is

backward-compatible to the traditional SPI protocol. Additionally, configurable

features simplify interface to a wide range of host controllers.