Advanced driver-assistance systems (ADAS) are features of some automobiles to reduce the human error associated with driving. ADAS may include safety features that alert drivers as well as automatic features. Automotive Safety Integrity Level (ASIL) is a risk classification scheme, and is divided into standards A, B, C, and D, with ASIL-D being the most rigorous safety requirement standard.
The Internet of Things (IoT) is a network of devices embedded with electronics, software, and sensors to enable the exchange and analysis of data. Many IoT devices operate using a system-on-a-chip (SoC), which includes processor cores as well as memory controller, input/output ports, video, graphics, and so on, on a single chip. SoC-based IoT devices are used in the automobile industry, with SoC-enabled vehicles sharing data with the cloud, infrastructure, and other vehicles.
IoT systems targeting automotive and industrial segments may feature ADAS, and these devices are designed according to the highest ASIL standard, ASIL-D. This ensures that the real-time IoT device performs safely and reliably under complex and noisy environments during the product's life cycle. A robust safety solution would involve diagnosis and early reporting of faults to a system agent so that the IoT device may be parked safely or put into a recovery state or reset states. One of the fault conditions to consider is power supply voltage droop.
Power-based systems are designed to address changes in current requirements at the load. A microprocessor load, for example, may change its current consumption by 50 amps or more in a fraction of a nanosecond, or a single cycle. This current spike causes voltage variations or spikes, known as droops, on the power supply. A droop is defined as steady state output voltage change as a function of time and may include both under-voltage and over-voltage conditions.