Product details

Resolution (Bits) 12 Sample rate (max) (ksps) 1250 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) 36 Analog supply (min) (V) 4.75 Analog supply voltage (max) (V) 5.25 SNR (dB) 73.5 Digital supply (min) (V) 1.65 Digital supply (max) (V) 5.25
Resolution (Bits) 12 Sample rate (max) (ksps) 1250 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) 36 Analog supply (min) (V) 4.75 Analog supply voltage (max) (V) 5.25 SNR (dB) 73.5 Digital supply (min) (V) 1.65 Digital supply (max) (V) 5.25
TSSOP (PW) 16 32 mm² 5 x 6.4
  • 12-bit ADC with integrated analog front-end
  • High speed:
    • ADS8661: 1.25 MSPS
    • ADS8665: 500 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: ±0.1 LSB; INL: ±0.15 LSB
    • SNR: 74 dB; THD: –102 dB
  • ALARM → high, low threshold
  • multiSPI™ interface with daisy-chain
  • Extended industrial temperature range: –40°C to +125°C
  • 12-bit ADC with integrated analog front-end
  • High speed:
    • ADS8661: 1.25 MSPS
    • ADS8665: 500 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: ±0.1 LSB; INL: ±0.15 LSB
    • SNR: 74 dB; THD: –102 dB
  • ALARM → high, low threshold
  • multiSPI™ interface with daisy-chain
  • Extended industrial temperature range: –40°C to +125°C

The ADS8661 and ADS8665 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 ADS8661 and ADS8665 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 View video with transcript Video

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 (...)

User guide: PDF
Not available on TI.com
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 operational-amplifier (...)
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 (...)
User guide: PDF
Package Pins Download
TSSOP (PW) 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