共查询到17条相似文献,搜索用时 281 毫秒
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本文介绍了采用作者提出的新型CCT工作原理而研制成功的集成CMOS流量传感器.这种传感器采用常规CMOS工艺制备而不需要任何附加工艺步骤.为了提高传感器的稳定性,其电路结构作了进一步改进.该传感器采用单个5伏电源,其输出信号可与A/D及微处理器自然接口.芯片尺寸为1×1.9mm~2,灵敏度高达70mV(T_(芯片)=27℃,T_(液体)=19℃,流速40cm/s),响应时间为40秒(流速为24cm/s时).在CMOS运算放大器(A)设计中,采用二级偏置电路以满足偏压要求并具有极好的温度性能.文中对CMOS运算放大器的设计作了较细致的讨论. 相似文献
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在室温情况下,研究了MIS结构电容器的湿敏特性。用交流串联电路,测量其电流与相对湿度和频率的依赖关系,实验结果表明:此结构有良好的感湿灵敏度和短的响应时间。其中相对湿度从12%变化到98%时,在较宽频率范围(102~105Hz)内,元件的电流有较大的变化。还对器件的物理模型进行了分析。 相似文献
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Kh. S. Karimov M. Saleem M. Mahroof-Tahir R. Akram M. T. Saeed Chanee A. K. Niaz 《半导体学报》2014,35(9):094001-4
A resistive-type relative humidity (RH) sensor based on vanadium complex (VO2(3-f[)) film is reported in this study. Gold electrodes were deposited on the glass substrates in a co-planar structure. A thin film of vanadium complex was coated as a humidity-sensing material on the top of the pre-patterned electrodes. The humidity-sensing principle of the sensor was based on the conductivity change of coated sensing element upon adsorption/desorption of water vapor. The resistance of the humidity sensor measured at 1 kHz decreased linearly with increasing the humidity in the range of 35%-70% RH. The overall resistance of the sensor decreases 11 times. An equivalent circuit for the VO2(3-fl) based resistive-type humidity sensor was developed. The properties of the sensor studied in this work make it beneficial for use in the instruments for environmental monitoring of humidity. 相似文献
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研究了一种新颖的碳纳米管气态离化结构的碳纳米管气体湿度传感器。该传感器具有一对或多对叉指状侧壁电极结构,电极上覆盖一层多壁碳纳米管薄膜,其利用碳纳米管高长径比的尖端电场收敛作用增大局部电场,有效地增强了传感器对气体湿度的敏感性。通过搭建的气体湿度测试平台,对传感器的静态和动态气体湿度特性进行了研究,结果显示传感器对60%以上相对气体湿度表现出了较强的灵敏度。与吸附式等传统气体湿度传感器对比,该气体湿度传感器具有较快的响应速度(约为0.15 s)和回复速度(约为0.6 s),较传统湿度传感器高了一个数量级,能够用于实时并且快速的气体湿度参量标定。 相似文献
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随着工业的快速发展,对温度检测和控制日益严格,温度传感器已无法跟上人们的需求,通过优化湿度传感器的表面结构和对感湿材料微孔设计提高了感湿特性,增强感湿材料的感湿特性,并对湿度传感器测量电路进行改进,提高微小电容测量,设计湿度测试系统。通过实验验证了改进后的湿度传感器测量效果更优越。 相似文献
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Liyun Ma Ronghui Wu Aniruddha Patil Shuihong Zhu Zhaohui Meng Haiqiang Meng Chen Hou Yifan Zhang Qiang Liu Rui Yu Jun Wang Naibo Lin Xiang Yang Liu 《Advanced functional materials》2019,29(43)
Textile‐based electronic techniques that can in real‐time and noncontact detect the respiration rate and respiratory arrest are highly desired for human health monitoring. Yarn‐shaped humidity sensor is fabricated based on a sensitive fiber with relatively high specific surface area and abnormal cross‐section. The response and recovery time of the yarn‐shaped humidity sensor is only 3.5 and 4 s, respectively, with little hysteresis, because of the hydrophobic property of these functional fibers and the grooves on the surface of the fibers, which is much faster than those of the commercial polyimide materials. Moreover, a battery‐free LC wireless testing system combined with the yarn‐shaped sensor is fabricated, which is further successfully imbedded into the intelligent mask to detect human breath. Based on the detection of LC wireless testing system, the frequency of 50.25 MHz under the exhaled condition shifts to 50.86 MHz under the inhaled situation of humidity sensor. In essence, the functional yarns with proper structure, would be an excellent candidature to the yarn‐shaped humidity sensor, in which there are good performance and wide application possibilities, eventually offering a facile method for the wireless detection of human physiological signals in the field of electronic fabrics. 相似文献
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传统湿度传感器制造工艺复杂、需有线连接信号,对此,文中提出一种纸基无芯片射频识别(Radio
Frequency Identification,RFID)湿度传感器。为提升传感器谐振特性,选择非对称开口环内部分布式加载金属碎片作
为传感器结构,聚乙烯醇(PVA)作为湿敏材料,使用遗传算法和HFSS 射频仿真软件来设计并优化传感器结构。以
喷墨打印技术制作传感器样品,采用滴涂法在传感器表面分别制备了5%、10%、15%三种质量浓度比的PVA 薄膜。
湿敏特性仿真及测试结果一致表明:PVA 与纸基底协同作用可显著提高传感器灵敏度。随PVA 浓度增加灵敏度增
加,15%PVA 传感器灵敏度最高,高湿灵敏度达到12. 22 MHz/ %RH,但随PVA 浓度增加恢复特性变差,5%PVA 湿度
传感器具有良好的恢复特性,恢复度达83. 87%。通过长期多次实验验证了PVA 纸基湿度传感器具有良好的温度稳
定性与中长期稳定性。与同类研究成果对比,文中设计在感湿范围及灵敏度方面有优势且制造工艺更简单,为低成
本湿度传感器的大规模使用提供了可能。 相似文献