Noise CMOS ISFETs Using In-Pixel Chopping
Noise CMOS ISFETs Using In-Pixel Chopping
复制标题
使用像素内斩波的噪声 CMOS ISFET
DOI：
10.1109/biocas.2019.8919025
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
J. Rosenstein
中科院分区：
文献类型：
--
作者：
Kangping Hu;Xiaoyu Lian;Shanshan Dai;J. Rosenstein
离子敏感场效应晶体管（isfet）是cmos兼容的pH传感器，已被广泛应用于生化传感应用。漂移和低频噪声是这些小型电荷敏感器件长期面临的挑战。然而，ISFET设计者经常避免使用斩波稳定的常见电路解决方案，因为可以理解的是，开关会干扰感测门。在这里，我们介绍了一种新的配置，它可以调制ISFET的源极和漏极电压，降低1/f噪声和漂移，而传感门的干扰可以忽略不计。我们利用氮化钛isfet在180纳米CMOS技术上实验证明了这种像素内斩波方案。使用像素内斩波，电路实现了三倍的漂移减少，同时抑制了1/f噪声。
Ion sensitive field effect transistors (ISFETs) are CMOS-compatible pH sensors which have been adopted for a wide range of biochemical sensing applications. Drift and low-frequency noise are perennial challenges for these small charge-sensitive devices. However, ISFET designers have often avoided the common circuit solution of chopper stabilization due to understandable concern that the switching will disturb the sensing gate. Here we introduce a new configuration which modulates the source and drain voltages of the ISFET, reducing 1/f noise and drift with negligible disturbance of the sensing gate. We experimentally demonstrate this in-pixel chopping scheme with titanium nitride ISFETs in 180-nm CMOS technology. Using in-pixel chopping, the circuit achieves a three-fold reduction in drift along with suppression of 1/f noise.