ADS1282 - Ultra-High-Resolution, 4kSPS, 2-Ch Delta-Sigma ADC With PGA for Seismic and Energy Exploration

The ADS1282 is an extremely high-performance, single-chip analog-to-digital converter (ADC) with an integrated, low-noise programmable gain amplifier (PGA) and two-channel input multiplexer (mux). The ADS1282 is suitable for the demanding needs of energy exploration and seismic monitoring environments.

The converter uses a fourth-order, inherently stable, delta-sigma (ΔΣ) 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 flexible input MUX provides an additional external input for measurement, as well as internal self-test connections. The PGA features outstanding low noise (5 nV/√Hz) and high input impedance, allowing easy interfacing to geophones and hydrophones over a wide range of gains.

The digital filter provides selectable data rates from 250 to 4000 samples per second (SPS). The high-pass filter (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 ADS1282s. The SYNC input also accepts a clock input for continuous alignment of conversions from an external source.

Together, the amplifier, modulator, and filter dissipate 25 mW. The ADS1282 is available in a compact TSSOP-28 package and is fully specified from –40°C to +85°C, with a maximum operating range to +125°C.

• High Resolution:
  130-dB SNR (250 SPS)
• High Accuracy:
  THD: –122 dB
  INL: 0.5 ppm
• Low-Noise PGA
• Two-Channel Input Mux
• Inherently-Stable Modulator with Fast Responding
  Overrange Detection
• Flexible Digital Filter:
  Sinc + FIR + IIR (Selectable)
  Linear or Minimum Phase Response
  Programmable High-Pass Filter
  Selectable FIR Data Rates: 250 SPS
  to 4 kSPS
• Filter Bypass Option
• Low Power Consumption: 25 mW
  Shutdown: 10 µW
• Offset and Gain Calibration Engine
• SYNC Input
• Analog Supply:
  Unipolar (+5 V) or Bipolar (±2.5 V)
• Digital Supply: 1.8 V to 3.3 V