Embedded analog performance monitors for reliable semiconductor circuits and systems

对于使命和安全关键系统，例如在太空、汽车、医疗保健或航空电子领域，早期检测潜在故障是必要的，以避免安全问题并保持低制造成本。类似的担忧也适用于从便利产品到近关键系统的廉价物联网（IoT）。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超出公认标准的工艺偏移的器件至关重要。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）器件，在自动测试设备（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方面是最佳的。该测试系统包括一个数字到模拟和模拟到数字数据转换器同步到一个参考采样时钟。遗憾的是，系统可以工作的最大频率受限于奈奎斯特采样原理，为数据转换器采样时钟的½倍。即使是最快的数据转换器，其采样频率也不超过50 GHz。这将工作频率上限设置为小于25 GHz。随着长距离数字和光通信的发展，数据速率高达400 Gbps，测量困难肯定会随之而来。同样，随着第五代无线系统的发展，28 GHz和70 GHz的工作频率也将遭受类似的命运。在这两种情况下，现有的相干抽样测试方法都不能适用。最近，申请人开发了一种基于相干子采样的新的测试方法。虽然子采样已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可合法追溯的嵌入式测试仪器，该仪器可以校准到外部直流电平;可能由现有的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.