摘要
针对植入式医疗设备中关键模块模数转换器(ADC)的超低功耗设计问题,以低功耗的逐次逼近型ADC为基础,提出了低位逐次逼近量化逻辑的模数转换器。量化逻辑主要用于以心电信号为代表的低活动度生物信号,在采用固定分辨率和采样率的情况下,根据信号的变化幅度调整量化次数,以达到降低功耗和压缩数据量的目的,在信号处于基线或缓变间期最少只需要3次量化就可以得到ADC转换结果。采用Global Foundry 0.18m标准CMOS工艺对该ADC进行了电路和版图设计,仿真结果显示,在1.8V的电源电压和1kHz的采样率下,ADC的有效位为9.6b,核心电路平均电流功耗为64~131nA。该低位逐次逼近模数转换器特别适合应用于植入或可穿戴医疗设备中低活动度生物信号的模数转换,在保证量化精度的同时显著降低了ADC的功耗。
Aiming at the ultra-low power consumption design of the indispensable analog-todigital converter(ADC)in implantable medical devices,based on the low-power-consumption successive-approximation SAR ADC,a least significant bit(LSB)-first SAR ADC is presented.The LSB-first quantitative logic is mainly used for biological signals of low mobility,such as electrocardiosignal.Under the condition of fixed resolution and sampling rate,the number of quantization is adjusted according to the amplitude of the varying signal,so as to achieve the purpose of reducing power consumption and compressing data amount.Only a minimum number of three quantizations is required to obtain a quantitative result when the signal in on the baseline or varies slowly.Global Foundry 0.18-μm standard CMOS process is used to design the circuit and layout of the ADC.The post-simulation results show that at the power supply voltage of 1.8 V and the sampling rate of 1 kHz,the effective bits are 9.6 bits,and the average current power consumption of the core circuit is 64-131 nA.The proposed LSB-first ADC can achieve high quantization accuracy while significantly reducing power consumption,and it is especially suitable for application in analog-to-digital conversion of low-mobility biological signals for implantable or wearable medical devices.
作者
许江涛
闫创
段颖哲
翟羽健
伍民顺
张瑞智
XU Jiangtao;YAN Chuang;DUAN Yingzhe;ZHAI Yujian;WU Minshun;ZHANG Ruizhi(School of Microelectronics,Xi’an Jiaotong University,Xi’an 710049,China)
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2020年第3期12-19,共8页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目（61404102,61774126）
中央高校基本科研业务费专项资金资助项目（xjj2018019）
关键词
植入式医疗设备
低功耗
低位逐次逼近
模数转换器
implantable medical device
low power consumption
least significant bit-first successive approximation
analog-to-digital converter
