Texas Instruments ADS8681 16-Bit SAR Analog-to-Digital Converters

Texas Instruments ADS8681 16-Bit SAR Analog-to-Digital Converters (ADCs) are an integrated data acquisition system based on a 16-Bit Successive Approximation (SAR) Analog-to-Digital Converter (ADC). This device operates at a throughput of 1MSPS. The device features a high-precision SAR ADC, integrated Analog Front-End (AFE) input driver circuit, an overvoltage protection circuit up to ±20V. This device also includes an on-chip 4.096V reference with extremely low-temperature drift. Operating on a single 5V analog supply, the Texas Instruments ADS8681 can support true bipolar input ranges of ±12.288V, ±6.144V, ±10.24V, ±5.12V, and ±2.56V. This ADC can also support unipolar input ranges of 0V to 12.288V, 0V to 10.24V, 0V to 6.144V, and 0V to 5.12V. The gain and offset errors for the AFE circuit are accurately trimmed within the specified values for each input range to ensure high DC precision.

Features

  • 16-bit ADC with integrated analog front-end
  • Software programmable input ranges
    • Bipolar ranges: ±12.288V, ±10.24V, ±6.144V, ±5.12V, and ±2.56V
    • Unipolar ranges: 0V–12.288V, 0V–10.24V, 0V–6.144V, and 0V–5.12V
  • 5V analog supply (1.65V to 5V I/O supply)
  • Constant resistive input impedance ≥ 1MΩ
  • Up to ±20V input overvoltage protection 
  • On-chip, 4.096V reference with low drift
  • Excellent performance
    • 1MSPS aggregate throughput 
    • DNL: ±0.4LSB; INL: ±0.5LSB
    • SNR: 92dB; THD: –107dB
  • ALARM → high, low thresholds per channel
  • multiSPI™ interface with daisy-chain
  • –40°C to 125°C industrial temperature range
  • Packages
    • 16-pin TSSOP (5.0mm x 4.4mm)
    • 16-pin WQFN (4.0mm x 4.0mm)

Applications

  • Channel-isolated PLC analog input modules
  • Test and measurement
  • Battery pack monitoring

Block Diagram

Block Diagram - Texas Instruments ADS8681 16-Bit SAR Analog-to-Digital Converters
Published: 2016-05-24 | Updated: 2022-03-11