A compact low-noise broadband digital picoammeter architecture
A compact low-noise broadband digital picoammeter architecture
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DOI：
10.1016/j.measurement.2016.12.040
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发表时间：
2017-03
期刊：
影响因子：
5.6
通讯作者：
M. Crescentini;M. Tartagni;H. Morgan;P. Traverso
中科院分区：
文献类型：
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作者：
M. Crescentini;M. Tartagni;H. Morgan;P. Traverso
提出了一种低噪声（104 fA/100 kHz）、宽带（100 kHz）紧凑型架构和相关操作解决方案，用于便携式和低成本的电流时域采集，有效分辨率为1 pA及以下。前端架构基于积分-微分方案，以实现输入参考等效噪声方面的最佳性能，但通过使A/D转换的采样频率与模拟前端复位速率无关，克服了典型的噪声/带宽权衡。为了强烈地减轻主要缺点，即，在系统中引入了一个固有的时间变化，一个与复位同步的跟踪保持电路被开发出来。为了验证的目的，一个双通道原型被实现在一个低成本的CMOS工艺。该原型的特点是标准的品质因数，并通过两个简单的案例研究，这是典型的实际应用实验验证。
A low-noise (⩽4 fA/√Hz), broadband (⩾100 kHz) compact architecture and related operation solutions are proposed for portable and low-cost time-domain acquisition of currents with effective resolution in the order of 1 pA and below. The front-end architecture is based on an integrating-differentiating scheme to achieve the optimal performance in terms of input-referred equivalent noise, but it overcomes the typical noise/bandwidth trade-off by making the sampling frequency of the A/D conversion independent from the rate at which the analog front-end is reset. In order to strongly mitigate the main drawback, i.e., the introduction in the system of an inherent time-variance, a Track-and-Hold circuit synchronized with the reset is exploited.For validation purposes, a dual-channel prototype was implemented in a low-cost CMOS technology. The prototype is characterized by standard figures of merit and is experimentally validated by two simple case studies, which are typical of practical applications.