ADS1218

The ADS1218 is a precision, wide dynamic range, delta-sigma, Analog-to- Digital (A/D) converter with 24-bit resolution and FLASH memory operating from 2.7V to 5.25V supplies. The delta-sigma, A/D converter provides up to 24 bits of no missing code performance and effective resolution of 22 bits.

The eight input channels of ADS1218 are multiplexed. Internal buffering can be selected to provide a very high input impedance for direct connection to transducers or low-level voltage signals. Burn out current sources are provided that allow for the detection of an open or shorted sensor. An 8-bit Digital-to-Analog (D/ A) converter provides an offset correction with a range of 50% of the FSR (Full-Scale Range).

The PGA (Programmable Gain Amplifier) provides selectable gains of 1 to 128 with an effective resolution of 19 bits at a gain of 128. The ADS1218 A/D conversion is accomplished with a second-order delta-sigma modulator and programmable sinc filter. The reference input is differential and can be used for ratiometric conversion. The on-board current DACs (Digital-to-Analog Converters) operate independently with the maximum current set by an external resistor.

The serial interface is SPI compatible. Eight bits of digital I/O are also provided that can be used for input or output. The ADS1218 is designed for high-resolution measurement applications in smart transmitters, industrial process control, weight scales, chromatography, and portable instrumentation.