Design And Implementation Of Portable ECG Monitor

The sudden onset of heart disease has made many people aware of the importance of monitoring their own ECG.ECG monitor is a modern medical instrument.It is the embodiment of high and new technology in medical instruments.The large multifunction monitor in hospital is complicated and needs professional operation.With the rapid development of electronic information technology in recent years,it is possible to design portable ECG monitors with low cost,small size,low power consumption,multiple functions and better stability.This paper conforms to the practical family gradually to the development direction of ECG monitor,after the analysis of the basic characteristics and basic functions of ECG monitor on the requirements,design a low-power and portable household ECG monitor.In hardware,the portable ECG monitor consists of two parts: front-end signal conditioning and digital signal processing.The front end is used as the input of ECG signal,and the ECG signal(bioelectricity signal)is picked up by three lead mode.After the pretreatment,including amplification,filtering and other conditioning process,after conditioning the signal into the analog to digital converter(ADC)analog to digital conversion,this paper uses ADS8881 to achieve the conversion of the ECG signal,the conversion precision,speed and ultra low power can meet the needs of system design.Digital signal processing using ultra low power single chip processor as the core circuit,these include digital filtering,the noise elimination signal,QRS wave detection,in order to achieve the extraction and determination of R wave,and abnormal heart rate analysis and data storage.The system also designed the USB interface,which can transfer the stored ECG information to the host computer for display.The display interface is drawn by VC++6.0,and the data can be saved for subsequent medical diagnostic applications.The system is powered by a lithium battery,which can charge the battery through the USB interface.Considering that the system is a portable device,it must have the basic characteristics of long standby time.Therefore,the design of ultra-low power hardware circuit is adopted,including the choice of processor.The overall functional performance shows that the ECG monitor designed in this paper is similar to the mature commercial products,and can be used for patient carrying and family use.