Design Of Portable ECG Monitor System Based On STM32

Conventional ECG devices (like 12-Channel ECG Holter System) are accurate and powerful which are used in large medical institutions. However, the devices also have limitations of high price, bulky volume and complex operation, which increased the economic burden of patients requiring hospitalization. In contrast, portable ECG monitor devices, based on the fast development of embedded system and integrated circuit technology, have the advantages of high processing capacity, low cost, portable and remote communication, bringing the Gospel to patients with cardiovascular disease. The devices are convenient for the patient’s daily life, timely access to disease surveillance data,improve the cure rate of cardiovascular disease.To this end, a portable ECG monitor system based on high performance embedded CPU is lucubrated in this thesis. While conducting researches on the theory of ECG, an ECG conditioning module is designed according to the features of ECG signals, which effectively improve the adaptation of individual differences. The module is divided into upper extremity conduction circuit, right leg drive circuit, differential circuit, band-pass filter circuit, main amplifier circuit, trap circuit, bias circuit, which achieves amplification and filtering of ECG, advances the signal’s voltage level to satisfy the level requested by A/D converter. The fixed gain acquisition circuit has poor adaptability to the individual difference of ECG waveform peak-peak value. In order to improve the circuit adaptability, a gain control circuit is designed in this paper. VGA chip AD603 is used to achieve intelligent gain control(862.6 to 2730 times adjustable gain range) of the signal conditioning module. The high-performance and low power ARM processor STM32F103ZET6 is used as the kernel of the system, μC/OS-Ⅱ operating system and FATFS file system is transplanted to complete system software design.The system have main functions of ECG data acquisition, waveform display by LCD, data analysis, SD card storage, USB transferring and Interactive interface using touch screen.The above work has been detailed described in this paper, and the tested results show the system has achieved design requirements. the system has the features of simple interface, clear ECG display,effective storage and transmission, providing the basis for the new ECG monitor devices.