Texas Instruments ADS869x SAR Analog-to-Digital Converters

Texas Instruments ADS869x SAR Analog-to-Digital Converters (ADCs) are an integrated data acquisition system based on successive approximation (SAR) ADCs. The devices feature a high-speed, high-precision SAR ADC and integrated analog front-end (AFE) input driver circuit. These devices also include an overvoltage protection circuit up to ±20V and an on-chip 4.096V reference with extremely low-temperature drift. The devices operate on a single 5V analog supply but support true bipolar input ranges of ±12.288V, ±6.144V, ±10.24V, ±5.12V, and ±2.56V. The Texas Instruments ADS869x 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 are accurately trimmed within the specified values for each input range to ensure high dc precision. The input range selection is made by software programming of the device's internal registers. The devices offer a high resistive input impedance (≥ 1MΩ) irrespective of the selected input range.

Features

  • 18-bit ADC with integrated analog front-end
  • High speed
    • ADS8691: 1MSPS
    • ADS8695: 500kSPS
    • ADS8699: 100kSPS
  • 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
  • Input overvoltage protection up to ±20V
  • On-chip, 4.096V reference with low drift
  • Excellent performance
    • DNL: ±0.6LSB; INL: ±1.75LSB
    • SNR: 92.5dB; THD: –110dB
  • ALARM → High, low thresholds per channel
  • multiSPI™ interface with daisy-chain
  • –40°C to +125°C extended industrial temperature range 

Applications

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

Functional Block Diagram

Block Diagram - Texas Instruments ADS869x SAR Analog-to-Digital Converters
Publicado: 2017-07-10 | Actualizado: 2022-05-27