Product details

Resolution (Bits) 16 Sample rate (max) (ksps) 500 Number of input channels 1 Interface type Enhanced SPI, SPI Architecture SAR Input type Single-ended Rating Catalog Reference mode External, Internal Input voltage range (max) (V) 12.288 Input voltage range (min) (V) -12.288 Features Oscillator, Over-Voltage Protection, PGA Operating temperature range (°C) -40 to 125 Power consumption (typ) (mW) 29 Analog supply (min) (V) 4.75 Analog supply voltage (max) (V) 5.25 SNR (dB) 92 Digital supply (min) (V) 1.65 Digital supply (max) (V) 5.25
Resolution (Bits) 16 Sample rate (max) (ksps) 500 Number of input channels 1 Interface type Enhanced SPI, SPI Architecture SAR Input type Single-ended Rating Catalog Reference mode External, Internal Input voltage range (max) (V) 12.288 Input voltage range (min) (V) -12.288 Features Oscillator, Over-Voltage Protection, PGA Operating temperature range (°C) -40 to 125 Power consumption (typ) (mW) 29 Analog supply (min) (V) 4.75 Analog supply voltage (max) (V) 5.25 SNR (dB) 92 Digital supply (min) (V) 1.65 Digital supply (max) (V) 5.25
TSSOP (PW) 16 32 mm² 5 x 6.4
  • 16-bit ADC with integrated analog front-end
  • High speed:
    • ADS8681: 1 MSPS
    • ADS8685: 500 kSPS
    • ADS8689: 100 kSPS
  • Software programmable input ranges:
    • Bipolar ranges: ±12.288 V, ±10.24 V, ±6.144 V, ±5.12 V, and ±2.56 V
    • Unipolar ranges: 0 V–12.288 V, 0 V–10.24 V, 0 V–6.144 V, and 0 V–5.12 V
  • 5-V analog supply: 1.65-V to 5-V I/O supply
  • Constant resistive input impedance ≥ 1 MΩ
  • Input overvoltage protection: Up to ±20 V
  • On-chip, 4.096-V reference with low drift
  • Excellent performance:
    • DNL: ±0.4 LSB; INL: ±0.5 LSB
    • SNR: 92 dB; THD: –107 dB
  • ALARM → high, low threshold
  • multiSPI™ interface with daisy-chain
  • Extended industrial temperature range: –40°C to +125°C
  • 16-bit ADC with integrated analog front-end
  • High speed:
    • ADS8681: 1 MSPS
    • ADS8685: 500 kSPS
    • ADS8689: 100 kSPS
  • Software programmable input ranges:
    • Bipolar ranges: ±12.288 V, ±10.24 V, ±6.144 V, ±5.12 V, and ±2.56 V
    • Unipolar ranges: 0 V–12.288 V, 0 V–10.24 V, 0 V–6.144 V, and 0 V–5.12 V
  • 5-V analog supply: 1.65-V to 5-V I/O supply
  • Constant resistive input impedance ≥ 1 MΩ
  • Input overvoltage protection: Up to ±20 V
  • On-chip, 4.096-V reference with low drift
  • Excellent performance:
    • DNL: ±0.4 LSB; INL: ±0.5 LSB
    • SNR: 92 dB; THD: –107 dB
  • ALARM → high, low threshold
  • multiSPI™ interface with daisy-chain
  • Extended industrial temperature range: –40°C to +125°C

The ADS8681, ADS8685, and ADS8689 belong to a family of integrated data acquisition system based on a successive approximation (SAR) analog-to-digital converter (ADC). The devices feature a high-speed, high-precision SAR ADC, integrated analog front-end (AFE) input driver circuit, overvoltage protection circuit up to ±20 V, and an on-chip 4.096-V reference with extremely low temperature drift.

The devices operate on a single 5-V analog supply, but support true bipolar input ranges of ±12.288 V, ±6.144 V, ±10.24  V, ±5.12 V, and ±2.56 V, as well as unipolar input ranges of 0  V to 12.288 V, 0  V to 10.24 V, 0  V to 6.144 V, and 0 V to 5.12 V. 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 done by software programming of the device internal registers. The devices offer a high resistive input impedance (≥ 1 MΩ) irrespective of the selected input range.

The multiSPI digital interface is backward-compatible to the traditional SPI protocol. Additionally, configurable features simplify interface to a wide range of host controllers.

The ADS8681, ADS8685, and ADS8689 belong to a family of integrated data acquisition system based on a successive approximation (SAR) analog-to-digital converter (ADC). The devices feature a high-speed, high-precision SAR ADC, integrated analog front-end (AFE) input driver circuit, overvoltage protection circuit up to ±20 V, and an on-chip 4.096-V reference with extremely low temperature drift.

The devices operate on a single 5-V analog supply, but support true bipolar input ranges of ±12.288 V, ±6.144 V, ±10.24  V, ±5.12 V, and ±2.56 V, as well as unipolar input ranges of 0  V to 12.288 V, 0  V to 10.24 V, 0  V to 6.144 V, and 0 V to 5.12 V. 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 done by software programming of the device internal registers. The devices offer a high resistive input impedance (≥ 1 MΩ) irrespective of the selected input range.

The multiSPI digital interface is backward-compatible to the traditional SPI protocol. Additionally, configurable features simplify interface to a wide range of host controllers.

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Evaluation board

ADS8681EVM-PDK — ADS8681 16-Bit 1MSPS Single-Supply SAR ADC EVM Performance Development Kit (PDK)

The ADS8681 evaluation module (EVM) performance demonstration kit (PDK) is a platform for evaluating the performance of the ADS8681 successive approximation register analog-to-digital converter (SAR ADC). The ADS8681EVM-PDK includes the ADS8681 EVM board, the PHI controller board, and (...)

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Simulation tool

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