Product details

Resolution (Bits) 16 Number of input channels 1 Sample rate (Max) (kSPS) 1000 Interface type SPI, Enhanced SPI Architecture SAR Input type Single-Ended Multi-channel configuration Rating Catalog Reference mode Ext, Int Input range (Max) (V) 12.288 Input range (Min) (V) -12.288 Features Oscillator, Over-Voltage Protection, PGA Operating temperature range (C) -40 to 125 Power consumption (Typ) (mW) 42 Analog voltage AVDD (Min) (V) 4.75 SNR (dB) 90.5 Analog voltage AVDD (Max) (V) 5.25 INL (Max) (+/-LSB) 1.2 Digital supply (Min) (V) 1.65 Digital supply (Max) (V) 5.25
Resolution (Bits) 16 Number of input channels 1 Sample rate (Max) (kSPS) 1000 Interface type SPI, Enhanced SPI Architecture SAR Input type Single-Ended Multi-channel configuration Rating Catalog Reference mode Ext, Int Input range (Max) (V) 12.288 Input range (Min) (V) -12.288 Features Oscillator, Over-Voltage Protection, PGA Operating temperature range (C) -40 to 125 Power consumption (Typ) (mW) 42 Analog voltage AVDD (Min) (V) 4.75 SNR (dB) 90.5 Analog voltage AVDD (Max) (V) 5.25 INL (Max) (+/-LSB) 1.2 Digital supply (Min) (V) 1.65 Digital supply (Max) (V) 5.25
TSSOP (PW) 16 22 mm² 5 x 4.4 WQFN (RUM) 16 16 mm² 4 x 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.

Download

Technical documentation

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

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 (...)

In stock
Limit: 3
Evaluation board

PSIEVM — Precision Signal Injector (PSI) Evaluation Module for Testing ADC Performance

The precision signal injector (PSI) is a platform for evaluating the performance of successive-approximation register (SAR) analog-to-digital converters (ADCs). The board provides a low-distortion, low-noise, 2-kHz input signal for driving the input of the ADC, and pairs with most of the (...)

In stock
Limit: 3
Support software

ADS8681EVM GUI Software (Rev. B)

SBAC146B.ZIP (386316 KB)
Simulation model

ADS8681 TINA-TI Ref Design

SBAM266.ZIP (135 KB) - TINA-TI Reference Design
Simulation model

ADS8681 TINA-TI Spice Model

SBAM267.ZIP (40 KB) - TINA-TI Spice Model
Simulation model

ADS8681 IBIS Model

SBAM268.ZIP (36 KB) - IBIS Model
Simulation tool

PSPICE-FOR-TI — PSpice® for TI design and simulation tool

PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
Simulation tool

TINA-TI — SPICE-based analog simulation program

TINA-TI provides all the conventional DC, transient and frequency domain analysis of SPICE and much more. TINA has extensive post-processing capability that allows you to format results the way you want them. Virtual instruments allow you to select input waveforms and probe circuit nodes voltages (...)
Calculation tool

ADC-INPUT-CALC — Analog-to-digital converter (ADC) input driver design tool supporting multiple input types

ADC-INPUT-CALC is an online tool that provides support for designing the input buffer to an analog-to-digital converter (ADC). It offers 24 different op-amp based buffer circuits that can be used to drive an ADC input. The available topologies cover differential, single-ended and transformer-coupled (...)
Calculation tool

ANALOG-ENGINEER-CALC — Analog engineer's calculator

The Analog Engineer’s Calculator is designed to speed up many of the repetitive calculations that analog circuit design engineers use on a regular basis. This PC-based tool provides a graphical interface with a list of various common calculations ranging from setting op-amp gain with feedback (...)
Reference designs

TIDA-01333 — 8-ch Isolated High Voltage Analog Input Module with ISOW7841 Reference Design

The TIDA-01333 isolated high voltage analog input module reference design has eight channels supporting both, voltage and current measurement. In addition, 4 channels support common-mode voltages up to ±160V. Isolation of +5V line and the Serial Peripheral Interface  (SPI) communication (...)
Reference designs

TIDA-00764 — 8-ch Isolated High Voltage Analog Input Module Reference Design

This reference design is a high-voltage analog input module with eight channels. Each channel can be used for both voltage and current measurement. The design uses 16-bit analog-to-digital converter (ADC) ADS8681 that can handle input voltage of up to ±12.288 V. This make any (...)
Reference designs

TIDA-00106 — 16-Bit 1-MSPS Data Acquisition Reference Design, Isolated for High-Voltage Common-Mode Rejection

The circuit represents a high-performance data acquisition (DAQ) solution suitable for processing input signals (up to ±12 V) superimposed on large common-mode offsets (tested up to 155 Vp-p from dc to approximately 15 kHz) relative to the ground potential of the system's main power supply (...)
Package Pins Download
TSSOP (PW) 16 View options
WQFN (RUM) 16 View options

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring

Recommended products may have parameters, evaluation modules or reference designs related to this TI product.

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos