A Reconfigurable Tri-Mode Frequency-Locked Loop Readout Circuit for Biosensor Interfaces.
A Reconfigurable Tri-Mode Frequency-Locked Loop Readout Circuit for Biosensor Interfaces.
复制标题
用于生物传感器接口的可重构三模式锁频环读出电路。
DOI：
10.1109/tbcas.2023.3288505
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发表时间：
2023
影响因子：
5.1
通讯作者：
Johnston,MatthewL
中科院分区：
文献类型：
--
作者：
Yu,Siyuan;Chou,Tzu-Hsuan;Bose,Soumya;Cook,Jacob;Park,Jaehyeong;Johnston,MatthewL
在这篇文章中，一个基于锁频环（FLL）的多模态读出集成电路（IC）与芯片外的温度，电化学和pH传感器接口。通过重新配置其开关电容反馈网络，读出电路能够测量电阻，电流和电压，而无需额外的有源模拟前端电路。采用0.18 μ mCMOS工艺制作了原型电路。测量结果表明，在100 Hz积分带宽下，该电路测量电阻时的输入参考电阻分辨率为10.5。使用片外热敏电阻，读出电路覆盖的温度范围为0- 75 ℃，并实现了16.4 mKrms的等效温度分辨率。在电流模式下，读出电路的输入范围为0.5μA，100 Hz带宽下的输入参考电流噪声低至40.6 pArms。与芯片上的恒电位仪接口，葡萄糖计时电流法证明。在电压模式下，该集成电路的最小输入参考电压噪声为31.7 μ Vrms，使用市售pH探针可以测量1.6 ~ 12的pH值。在1.2 V电源电压下，三种测量模式下读出电路的功耗均低于10 μW。此外，原型IC包括一个集成的无线发射器，实现开关键控调制，和一个无线多模态传感系统，利用FLL为基础的读出电路进行了演示。
In this article, a frequency-locked loop (FLL) based multimodal readout integrated circuit (IC) for interfacing with off-chip temperature, electrochemical, and pH sensors is presented. By reconfiguring its switched-capacitor feedback network, the readout circuit is able to measure resistance, current, and voltage without additional active analog front-end circuits. A prototype IC was fabricated in a 0.18 μm CMOS process. Measured results show that when measuring resistance, the input-referred resistance resolution is 10.5for 100 Hz integration bandwidth. Using an off-chip thermistor, the readout circuit covers a temperature range of 0–75C and achieves an equivalent temperature resolution of 16.4 mKrms. In current mode, the readout circuit has an input range of 0.5μA and an input-referred current noise as low as 40.6 pArmsfor 100 Hz bandwidth. Interfacing with an on-chip potentiostat, glucose chronoamperometry is demonstrated. In voltage mode, a minimum input-referred voltage noise of 31.7 μVrmsis achieved, and the IC can measure a pH range from 1.6 to 12 using a commercial pH probe. At a 1.2 V supply, power consumption of the readout circuit is below 10 μW for all three measurement modes. Additionally, the prototype IC includes an integrated wireless transmitter that implements on-off keying modulation, and a wireless multimodal sensing system utilizing the FLL-based readout circuit is demonstrated.