AAD-KWS: A Sub-µW Keyword Spotting Chip with a Zero-Cost, Acoustic Activity Detector from a 170nW MFCC Feature Extractor in 28nm CMOS

Abstract

**Please read the paper on the following link:** https://1worldcontent.com/ess/9296.pdf **Abstract:** We propose an always-on keyword spotting chip with an acoustic activity detection (AAD). Extracted from feature extractor, this AAD has zero overhead and zero miss rate. We also propose a tunable detection window to fit keywords with different widths to get better accuracy. Besides, a non-overlapping-frame Mel frequency cepstrum coefficient is used in the KWS system to reduce memory footprint and processing cycles. Implemented in a 28nm CMOS technology, its power consumption is only 0.36μW for AAD and 0.8μW for KWS at 0.4V. And MFCC circuit has only 170nW power consumption. The accuracy can reach 97.8% for two keywords.