Texas Instruments ADS8661W 12-Bit High-Speed SAR ADC
Texas Instruments ADS8661W 12-Bit High-Speed SAR Analog-to-Digital Converter (ADC) is an integrated data acquisition system based on a successive approximation (SAR) analog-to-digital converter (ADC) topology. The device features a high-speed, high-precision SAR ADC integrated differential analog front-end (AFE) input driver circuit. The ADS8661W includes an overvoltage protection circuit of up to ±20V and an on-chip 4.096V reference with extremely low temperature drift.
The Texas Instruments ADS8661W operates on a single 5V analog supply but supports true bipolar input ranges and unipolar input ranges. The bipolar input ranges are ±12.288V, ±6.144V, ±10.24V, ±5.12V, and ±2.56V, and the unipolar input ranges are from 0V to 12.288V, 10.24V, 6.144V, and 5.12V. The devices offer a high resistive input impedance (≥1MΩ) irrespective of the selected input range.
The multiSPI digital interface is backward compatible with the traditional SPI protocol. Additionally, configurable features simplify the interface to a wide range of host controllers.
Features
- 12-bit ADC with integrated analog front-end
- High speed of 1.25MSPS
- Software programmable input ranges
- Bipolar differential ranges: ±12.288V, ±10.24V, ±6.144V, ±5.12V, and ±2.56V
- Unipolar differential ranges: 0V to 12.288V, 0V to 10.24V, 0V to 6.144V, and 0V to 5.12V
- Analog supply (5V) of 1.65V to 5V I/O supply
- Constant resistive input impedance ≥ 1MΩ
- 450kHz input bandwidth
- Input overvoltage protection of up to ±20V
- On-chip, 4.096V reference with low drift
- Excellent performance
- DNL: ±0.1LSB; INL: ±0.15LSB
- SNR: 74dBFS; THD: –102dB
- ALARM feature with a high and low threshold
- multiSPI interface with daisy-chain
- Extended industrial temperature range of –40°C to +125°C
Applications
- Analog input modules
- Semiconductor tests
- Servo drive control modules
Block Diagram
Published: 2025-05-12
| Updated: 2025-05-20