A portable low-power 7-lead ECG recorder with a new analogue front-end IC

Abstract

As a consequence of the high relevance of heart diseases, the design of new portable devices able to continuously record heart activity has been promoted by the increasing number of patients requiring long term heart monitoring. Nowadays, for a successful commercialization, these devices need to satisfy two main expectations: the first one is a long battery lifetime and the second one is the possibility to interface with the device through a smartphone or a laptop. This paper aims both to address to these two demands and to provides enough information about heart activity; this work is intended to ensure the proper ECG signal detection and visualization from 7 leads. For these reasons, a low-power Holter system, integrated with a previously developed low power analogue front-end (AFE) IC chip is presented; this is the first time that such AFE has been used for this application. The system is also composed by a STM32L152 microprocessor, a HHW UART S10 Bluetooth module, a MultiMediaCard(MMC)-based data storage module, a power management unit and other discrete components. The system works with a single 1.8V power supply and the power required is around 40mW (excluding the Bluetooth module the power decreases down to 18mW).