Texas Instruments ADS888x 18-Bit SAR Analog-to-Digital Converters are 18-bit, true-differential input, analog-to-digital converters (ADCs). These devices operate with a 2.5V to 5V external reference, offering a wide selection of signal ranges without additional input signal scaling. The reference voltage setting is independent of, and can exceed, the analog supply voltage (AVDD). The device offers an SPI-compatible serial interface that also supports daisy-chain operation for cascading multiple devices. An optional busy-indicator bit (available for ADS8883, ADS8887 only) makes synchronizing with the digital host easy. Device operation is optimized for very low-power operation. Power consumption directly scales with speed. This feature makes the ADS888x excellent for lower-speed applications.