摘要
Abstract
Impedance detection principle based on the AD5933 and the hardware and software implementation are introduced in this paper. System design uses the AD5933 impedance measurement chip, with a low consumption of high-performance processor STC89C52 MCU as the controller. The detector adopts the AD5933 digital frequency synthesizer (DDS) in the excitation signal is produced, imposed on the impedance under test, the ADC acquisition signal and sent to the corresponding chip DFT digital processing module, measurement results through the I2C sent to the microcontroller, again by the single-chip microcomputer and PC computer communication, the computer shows that the impedance values. At the same time also can according to the relationship of impedance blood flow and blood sugar to further realize the noninvasive detection of blood sugar levels. The instrument can realize the resistor, capacitor, inductance impedance measuring rapidly and accurately, through experimental verify that resistive impedance deviation from the mean is 0.0411, phase deviation from the mean is 0.152°, aqueous solution of glucose concentration was linearly correlated with the impedance, the correlation coefficient greater than 0.99.关键词
AD5933/阻抗检测/STC89C52 单片机/上位机Key words
AD5933/impedance detection/STC89C52 MCU/PC分类
计算机与自动化
