11.1 An oversampled 12/14b SAR ADC with noise reduction and linearity enhancements achieving up to 79.1dB SNDR
11.1 An oversampled 12/14b SAR ADC with noise reduction and linearity enhancements achieving up to 79.1dB SNDR
复制标题
DOI：
10.1109/isscc.2014.6757396
复制
发表时间：
2014-03
期刊：
影响因子：
--
通讯作者：
P. Harpe;E. Cantatore;A. Roermund
中科院分区：
文献类型：
--
作者：
P. Harpe;E. Cantatore;A. Roermund
云网络的自主无线传感器节点需要超低功耗电子器件。特别是传感器读出接口需要低速高精度模数转换器（ADC）来采集例如生物电位信号、环境信息或交互式多媒体等。对于这些应用，最先进的逐次逼近寄存器（SAR）ADC能够提供高能效的解决方案（每次转换步长功耗<10飞焦），但精度有限（信噪失真比<63分贝）[1,2]。或者，ΔΣ ADC以较低效率为代价提供更高精度（例如，信噪失真比为84分贝，每次转换步长功耗为54飞焦[3]）。这项工作通过将低功耗SAR ADC的精度扩展到信噪失真比为70至80分贝的量级，弥合了现有的性能差距。反馈控制的数据驱动降噪[1]、过采样、斩波[4]和抖动[5]技术相结合，以高能效的方式提高信噪比和线性度。通过使这些技术可单独编程来支持各种ADC模式，从而扩展了应用范围。
Autonomous wireless sensor nodes for cloud networks require ultra-low-power electronics. In particular, sensor readout interfaces need low-speed high-precision ADCs for capturing, e.g., bio-potential signals, environmental information, or interactive multimedia. For these applications, state-of-the-art SAR ADCs can provide highly power-efficient solutions (<;10fJ/conversion-step) but with limited accuracy (SNDR <;63dB) [1,2]. Alternatively, ΔΣ ADCs offer higher precision at the cost of lower efficiency (e.g. 84dB SNDR with 54fJ/conversion-step [3]). This work bridges the existing performance gap by extending the accuracy of low-power SAR ADCs to SNDRs in the order of 70-to-80dB. Feedback-controlled data-driven noise reduction [1], oversampling, chopping [4] and dithering [5] techniques are combined to increase both SNR and linearity in a power-efficient way. Various ADC modes are supported by making these techniques individually programmable, thereby extending the application range.