A micropower analog-digital heart rate detector chip

Abstract

Abstract. A micropower detector chip integrated with CMOS technology has been developed for a hand-held heart rate monitoring instrument mainly used by professional athletes and others who exercise seriously to increase their endurance and overall performance. The chip uses linear bandpass filtering and threshold detection and is implemented with analog switched-capacitor (SC) and digital techniques. The bandpass filter transfer function is derived from the spectral contents of noisy ECG signals. The layout was designed in full custom style in order to minimize the silicon area. The chip achieves a detection rate of 90 % with a simulated ECG signal corrupted with Gaussian noise (signal-to-noise ratio = 5) in the heart rate range 60-200 1/min with a total current consumption of less than 30 pA from a 3-V supply. The detection rate is 96.9% for a noisy signal obtained from the MIT-BIH arrhythmia database.

Low power current sources for bioimpedance measurements: a comparison between Howland and OTA-based CMOS circuits

“…Its availability for emerging wearable applications (16) and for on-chip systems such as the AD5933 (17,18) have also made its popularity grow. Microelectronics systems applied to health care solutions provide the advantages of small size devices, possible wireless signal and power transmission, portability, long time implant for low power circuits, and the possibility of improving the sensing of weak signals (on the order of milivolts) by taking them out in-situ (19)(20)(21).…”