This paper presents a high precision CMOS opamp suitable for ISFET readout. The opamp is tailored to provide a constant bias condition for ISFET as part of the readout circuits and,hence,is compatible for single chip ...This paper presents a high precision CMOS opamp suitable for ISFET readout. The opamp is tailored to provide a constant bias condition for ISFET as part of the readout circuits and,hence,is compatible for single chip integration with the sensor. A continuous time auto-zero stabilization technique is studied and employed, with the aim of suppressing the low frequency noises, including the offset voltage, 1/f noise, and temperature drift. The design is based on a 0.35μm CMOS process. With a 3.3V power supply,it maintains a DC open loop gain of more than 100dB and an offset voltage of around 11μV,while the overall power dissipation is only 1.48mW. With this opamp, a pH microsensor is constructed, of which the functionality is verified by experimental tests.展开更多
Ion-sensitive field-effect transistor (ISFET)-based biosensor for amino acids was proposed, and the response of the sensor to amino acids was evaluated. As a molecular recognition element, aminoacyl-tRNA synthetase ...Ion-sensitive field-effect transistor (ISFET)-based biosensor for amino acids was proposed, and the response of the sensor to amino acids was evaluated. As a molecular recognition element, aminoacyl-tRNA synthetase which would be expected to have high selectivity for the corresponding amino acids was used, aminoacyl-tRNA synthetase was coated onto an ISFET electrode, and the response of the biosensor to amino acids was evaluated. The amino acid sensor for tyrosine showed a selective response to tyrosine because of the specific binding ability of aminoacyl-tRNA synthetase for tyrosine and from 300μM to 900 μM of tyrosine could be measured (r2 〉 0.969).展开更多
ISFET(Ion Sensitive Field Effect Transistors)是1种可与CMOS工艺兼容的离子敏感场效应晶体管.随着传感器阵列集成度的不断增加,鉴于响应速度、功耗和成本的局限性,单个ISFET的检测电路不适于大规模集成化的检测系统.从集成化的角度出...ISFET(Ion Sensitive Field Effect Transistors)是1种可与CMOS工艺兼容的离子敏感场效应晶体管.随着传感器阵列集成度的不断增加,鉴于响应速度、功耗和成本的局限性,单个ISFET的检测电路不适于大规模集成化的检测系统.从集成化的角度出发,在分析多个读出电路的基础上,比较各自的性能特点,得出1种脉冲宽度调节读出电路,在功耗、转换速度和结构方面都有优势,适合于大规模ISFET传感器阵列的数据读取.并应用分立元件对电路性能进行了验证,通过FPGA采集读出电路输出数据,验证其具有良好的稳定性和可行性.展开更多
文摘This paper presents a high precision CMOS opamp suitable for ISFET readout. The opamp is tailored to provide a constant bias condition for ISFET as part of the readout circuits and,hence,is compatible for single chip integration with the sensor. A continuous time auto-zero stabilization technique is studied and employed, with the aim of suppressing the low frequency noises, including the offset voltage, 1/f noise, and temperature drift. The design is based on a 0.35μm CMOS process. With a 3.3V power supply,it maintains a DC open loop gain of more than 100dB and an offset voltage of around 11μV,while the overall power dissipation is only 1.48mW. With this opamp, a pH microsensor is constructed, of which the functionality is verified by experimental tests.
文摘Ion-sensitive field-effect transistor (ISFET)-based biosensor for amino acids was proposed, and the response of the sensor to amino acids was evaluated. As a molecular recognition element, aminoacyl-tRNA synthetase which would be expected to have high selectivity for the corresponding amino acids was used, aminoacyl-tRNA synthetase was coated onto an ISFET electrode, and the response of the biosensor to amino acids was evaluated. The amino acid sensor for tyrosine showed a selective response to tyrosine because of the specific binding ability of aminoacyl-tRNA synthetase for tyrosine and from 300μM to 900 μM of tyrosine could be measured (r2 〉 0.969).
文摘ISFET(Ion Sensitive Field Effect Transistors)是1种可与CMOS工艺兼容的离子敏感场效应晶体管.随着传感器阵列集成度的不断增加,鉴于响应速度、功耗和成本的局限性,单个ISFET的检测电路不适于大规模集成化的检测系统.从集成化的角度出发,在分析多个读出电路的基础上,比较各自的性能特点,得出1种脉冲宽度调节读出电路,在功耗、转换速度和结构方面都有优势,适合于大规模ISFET传感器阵列的数据读取.并应用分立元件对电路性能进行了验证,通过FPGA采集读出电路输出数据,验证其具有良好的稳定性和可行性.