Embedded analog performance monitors for reliable semiconductor circuits and systems

对于任务和安全关键型系统，如太空、汽车、医疗保健或航空电子领域，早期发现潜在问题对于避免安全问题和保持低制造成本是必要的。类似的担忧也适用于廉价的物联网（IoT），从便利产品到近乎关键的系统。为了确保可靠性，半导体集成电路（IC）制造商筛选出那些包含制造缺陷、老化和可靠性影响或工艺变化超出可接受规范的器件是至关重要的。这些方法的核心是需要快速准确的测试仪器。为了测量模拟和射频（RF）电路行为，以及最近的微机电系统（MEMS）设备，自动测试设备（ATE）和嵌入式测试中使用的核心测量技术是相干采样测试方法。该方法在测试时间和测量精度上是最佳的。测试系统由数模和模数数据转换器组成，与参考采样时钟同步。不幸的是，系统可以操作的最大频率被奈奎斯特采样原理限制为数据转换器采样时钟的½倍。即使是最快的数据转换器的采样频率也不超过50 GHz。设置工作频率上限在25ghz以内。随着远程数字和光通信技术的进步，数据传输速率高达400gbps，测量难度肯定会随之而来。同样，随着第5代无线系统的发展，28ghz和70ghz的工作频率也将面临类似的命运。在任何一种情况下，现有的相干抽样检验方法都不能适用。最近，申请人开发了一种新的基于相干子抽样的测试方法。虽然子采样已经在微波仪器和其他应用中使用了几十年，但这项工作旨在开发一种合法可追溯的嵌入式测试仪器，该仪器可以校准到外部直流电平；可能由现有ATE提供。

For mission and safety-critical systems, such as in space, automotive, healthcare or avionic domains, an early detection of potential troubles is necessary to avoid safety issues and keep manufacturing costs low. A similar concern also applies to cheap Internet-of-Things (IoT) ranging from convenience products to near-critical systems. To ensure dependability, it is paramount that semiconductor integrated circuit (IC) manufacturers screen out those devices that contain manufacturing defects, aging and reliability effects, or process shifts beyond the accepted norms. At the core of these methods is the need for fast and accurate test instruments. For measuring analog and radio-frequency (RF) circuit behavior, and more recently microelectromechanical systems (MEMS) devices, a core measurement technology used in both automatic test equipment (ATE) and embedded test is a coherent sampling test methodology. This methodology is optimum in test time and measurement accuracy. The test system consists of a digital-to-analog and analog-to-digital data converter synchronized to a reference sampling clock. Unfortunately, the maximum frequency that the system can operate is limited by the Nyquist sampling principle to ½-times the sampling clock of the data converters. Even the fastest data converters operate with sampling frequencies no greater than 50 GHz. This sets the upper operating frequencies to less than 25 GHz. With advances in long-haul digital and optical communications reaching data rates as high as 400 Gbps, measurement difficulties are sure to follow. Similarly, with the development of 5th-generation wireless systems, operating frequencies of 28 GHz and 70 GHz, will suffer a similar fate. In either case, the existing coherent sampling test methodology cannot be applied. Recently, the applicant has developed a new test methodology based on coherent subsampling. While subsampling has been used for decades in microwave instrumentation and other applications, this work sets out to develop a legally-traceable embeddable test instrument that can be calibrated to an external DC level; possibly supplied by an existing ATE.