Texas Instruments ADS868x 16 位 SAR 模数转换器（ADC）
德州仪器 ADS8688 16 位、4 或 8 通道 SAR 模数转换器（ADC）是基于 16 位逐次逼近（SAR）模数转换器的集成数据采集系统，在 500kSPS 的吞吐率下工作。这些器件各输入通道带有集成模拟前端电路，并可提供高达 ±20V 的过压保护、支持自动和手动两种扫描模式的 4 通道或 8 通道多路复用器、以及低温度漂移的片上 4.096V 基准电压。采用 5V 单模拟电源供电时，该器件上的各输入通道均可支持 ±10.24V、±5.12V、和 ±2.56V 的实际双极输入范围以及 0V 到 10.24V 和 0V 到 5.12V 的单极输入范围。模拟前端在所有输入范围内的增益均经过精确微调，以确保高直流精度。输入范围的选择可通过软件进行编程设定，各通道输入范围的选择相互独立。该器件提供了一个 1MΩ 的恒定阻性输入阻抗（无论所选输入范围为何）。它还提供了用于连接数字主机的简单 SPI 兼容串行接口，并且支持以菊花链形式连接多个器件。数字电源可提供 1.65V 到 5.25V 范围内的电压，因此可直接连接各种主机控制器。
Operating on a single 5V analog supply, each input channel on the devices can support true bipolar input ranges of ±10.24V, ±5.12V, and ±2.56V, as well as unipolar input ranges of 0V to 10.24V and 0V to 5.12V. The gain of the analog front-end for all input ranges is accurately trimmed to ensure high dc precision. The input range selection is software-programmable and independent for each channel. The devices offer a 1MΩ constant resistive input impedance irrespective of the selected input range. Texas Instruments ADS868x also offers a simple SPI-compatible serial interface to the digital host and supports daisy-chaining of multiple devices. The digital supply operates from 1.65V to 5.25V, enabling a direct interface to a wide range of host controllers.
特性
- 16-Bit ADC with Integrated Analog Front-End
- Four or eight-channel MUX with Auto and Manual Scan
- Channel-Independent Programmable Input Ranges
- Bipolar: ±10.24V, ±5.12V, and ±2.56V
- Unipolar: 0V to 10.24V and 0V to 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
- 500kSPS Aggregate Throughput
- DNL: ±0.5LSB; INL: ±0.75LSB
- Low Drift for Gain Error and Offset
- SNR: 92dB; THD: -102dB
- Low Power: 65mW
应用
- Power Automation
- Protection Relays
- PLC Analog Input Modules
Block Diagram
