2.5D Chiplet Architecture for Embedded Processing of High Velocity Streaming Data

This dissertation presents an energy efficient 2.5D chiplet-based architecture for real-time probabilistic processing of high-velocity sensor data, from an autonomous real-time ubiquitous surveillance imaging system. This work addresses problems at all levels of description. At the lowest physical level, new standard cell libraries have been developed for ultra-low voltage CMOS synthesis, as well as custom SRAM memory blocks, and mixed-signal physical true random number generators based on the perturbation of Sigma-Delta structures using random telegraph noise (RTN) in single transistor devices. At the chip level architecture, an innovative compact buffer-less switched circuit mesh network on chip (NoC) capable of reaching very high throughput (1.6Tbps), finite packet delay delivery, free from packet dropping, and free from dead-locks and live-locks, was designed for this chiplet-based solution. Additionally, a second NoC connecting processors in the network, was implemented based on token-rings, allowing access to external DDR memory. Furthermore, a new clock tree distribution network, and a wide bandwidth DRAM physical interface have been designed to address the data flow requirements within and across chiplets. At the algorithm and representation levels, the Online Change Point Detection (CPD) algorithm has been implemented for on-line learning of background-foreground segmentation. Instead of using traditional binary representation of numbers, this architecture relies on unconventional processing of signals using a bio-inspired (spike-based) unary representation of numbers, where these numbers are represented in a stochastic stream of Bernoulli random variables. By using this representation, probabilistic algorithms can be executed in a native architecture with precision on demand, where if more accuracy is required, more computational time and power can be allocated. The SoC chiplet architecture has been extensively simulated and validated using state of the art CAD methodology, and has been submitted to fabrication in a dedicated 55nm GF CMOS technology wafer run. Experimental results from fabricated test chips in the same technology are also presented

7 TOPS/W Cellular Neural Network Processor Core for Intelligent Internet-of-Things

We discuss the architecture, implementation and testing of a simplicial Cellular Neural Network (CNN) vector processor core aimed at vision oriented intelligent Internet-of-Things (IoT) devices. The architecture comprises a linear array of 64 processing elements (PE), each connected to a 4 neighbor clique operating on 8-bit input and state data. A 3-bit simplicial parameter, allows multilevel function approximation and extends the functionality over previously reported chips. Input data vectors are stored in two 64 x 64 x 8-bit data caches. The chip is synthesized from a custom designed ultra low voltage CMOS library and fabricated in a 55nm CMOS technology. Dynamic voltage/frequency scaling allows operation at power supplies between 0.5 and 1.2 Volts allowing for a tradeoff between speed and power. The fabricated chip achieves an overall performance of 7.05 TOPS/W at 732fps, with a dynamic energy efficiency of 12.2fJ per operation (OP) at 1.2 Volts.Fil: Villemur, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Julian, Pedro Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Figliolia, Tomas. University Johns Hopkins; Estados UnidosFil: Andreou, Andreas. University Johns Hopkins; Estados Unido