The ADS1281 is an extremely high-performance, single-chip analog-to-digital converter (ADC) designed for the demanding needs of energy exploration and seismic monitoring environments. The single-chip design promotes board area savings for improvements in high-density applications.
The converter uses a fourth-order, inherently stable, delta-sigma () modulator that provides outstanding noise and linearity performance. The modulator is used either in conjunction with the on-chip digital filter, or can be bypassed for use with post-processing filters.
The digital filter consists of sinc and finite impulse response (FIR) low-pass stages followed by an infinite impulse response (IIR) high-pass filter (HPF) stage. Selectable decimation provides data rates from 250 to 4000 samples per second (SPS). The FIR low-pass stage provides both linear and minimum phase response. The HPF features an adjustable corner frequency. On-chip gain and offset scaling registers support system calibration.
The synchronization input (SYNC) can be used to synchronize the conversions of multiple ADS1281s. The SYNC input also accepts a clock input for continuous alignment of conversions from an external source.
Together, the modulator and filter dissipate only 12mW. The ADS1281 is available in a compact TSSOP-24 package and is fully specified from –40°C to +85°C, with a maximum operating range to +125°C.