Ultra-low energy security circuits for IoT applications

Low-area energy-efficient security primitives are key building blocks for enabling end-to-end content protection, user authentication, and consumer confidentiality in the IoT world that is estimated to surpass 50billion smart and connected devices by 2020. This paper describes design approaches that blend energy-efficient circuit techniques with optimal accelerator microarchitecture datapath, and hardware friendly arithmetic to achieve ultra-low energy consumption in security platforms for seamless adoption in area/battery constrained and self-powered systems. Industry leading energy-efficiency is demonstrated with three designs, fabricated and measured in advanced process technologies: 1) A 2040-gate arithmetically optimized composite-field Sbox based AES accelerator achieves 289Gbps/W peak energy-efficiency while offering 432Mbps throughput in 22nm tri-gate CMOS, 2) Hybrid Physically Unclonable Function (PUF) circuit leverages burn-in induced aging to reduce bit-error, followed by temporal-majority-voting, dark-bit masking, and error-correction conditioning techniques to generate a 100% stable full-entropy key with 190fJ/bit energy consumption in 22nm tri-gate CMOS. 3) A light-weight all digital TRNG uses in-line correlation suppressor and entropy-extractor circuits to achieve >0.99 min-entropy with 3pJ/bit measured energy-efficiency while operating down to 300mV in 14nm tri-gate CMOS.