A dual-mode ECG processor with difference-insensitive QRS detection and lossless compression

Abstract

This work presents a low power dual-mode electrocardiogram (ECG) processor with QRS detection and ECG signal lossless compression. An adaptive difference-insensitive filter is proposed to eliminate redundant information in signal for QRS detection, which helps minimize calculation power. It is also adopted as a noise estimator and used to improve the noise tolerance of the detector. Furthermore, in compression mode, linear predictor with a novel adaptive length encoder is applied to the ECG data lossless compression, achieving a compression ratio (CR) of 2.42 with 1.06 K gate count. Implemented in 40 nm CMOS technology, the processor has a total core area of 6806 µm², with 36 nW power consumption in detection mode and 7.3 nW in compression mode under a supply voltage of 0.5 V.