남경식 교수

Resistive bridge sensors are used in many application areas to measure changes in physical parameters. To amplify the resistive changes from sensing elements with high precision, various offset contributors in the resistive bridge and amplifiers should be minimized. This study proposes a low-noise resistive bridge sensor analog front-end (AFE) using a chopper-stabilized multipath current feedback instrumentation amplifier (CFIA) and an automatic offset cancellation loop. The proposed circuit exp

This paper proposes a cardiac electrogram acquisition and stimulation integrated circuit (IC) for single-chamber leadless pacemaker applications. The proposed IC features self-determining pacing by acquiring an intracardiac electrogram without an external digital signal processor (DSP). A novel current-feedback instrumentation amplifier (CFIA) is proposed to achieve high noise-power efficiency and high input impedance. In this proposed CFIA, the current-reused cascode differential-difference inp

Abstract We study the free probabilistic analog of optimal couplings for the quadratic cost, where classical probability spaces are replaced by tracial von Neumann algebras, and probability measures on $${\mathbb {R}}^m$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mi>m</mml:mi> </mml:msup> </mml:math> are replaced by non-commutative laws of m -tuples. We prove an analog of the Monge–Kantorovich duality which characterizes o

In this paper, a low-power and low-noise readout circuit for resistive-bridge microsensors is presented. The chopper-stabilized, recycling folded cascode current-feedback instrumentation amplifier (IA) is proposed to achieve the low-power, low-noise, and high-input impedance. The chopper-stabilized, recycling folded cascode topology (with a Monticelli-style, class-AB output stage) can enhance the overall noise characteristic, gain, and slew rate. The readout circuit consists of a chopper-stabili

This paper presents a potentiostat readout circuit with low-noise and mismatch-tolerant current mirror using chopper stabilization and dynamic element matching (DEM) for electrochemical sensors. Current-mode electrochemical sensors are widely used to detect the blood glucose and viruses in the diagnosis of various diseases such as diabetes, hyperlipidemia, and the H5N1 avian influenza virus (AIV). Low-noise and mismatch-tolerant characteristics are essential for sensing applications that require

Air flow measurements provide significant information required for understanding the characteristics of insect movement. This study proposes a four-channel low-noise readout integrated circuit (IC) in order to measure air flow (air velocity), which can be beneficial to insect biomimetic robot systems that have been studied recently. Instrumentation amplifiers (IAs) with low-noise characteristics in readout ICs are essential because the air flow of an insect’s movement, which is electrically conv

We establish the well-posedness of SDE with the additive noise when a singular drift belongs to the critical spaces. We prove that if the drift belongs to the Orlicz-critical space $L^{q,1}([0,T],L^p_x)$ for $p,q\in (1,\infty)$ satisfying $\frac{2}{q}+\frac{d}{p} =1$, then the corresponding SDE admits a unique strong solution. We also derive the Sobolev regularity of a solution under the Orlicz-critical condition.

Abstract Eigenvalues of Wigner matrices has been a major topic of investigation. A particularly important subclass of such random matrices, useful in many applications, are what are known as sparse or diluted random matrices, where each entry in a Wigner matrix is multiplied by an independent Bernoulli random variable with mean . Alternatively, such a matrix can be viewed as the adjacency matrix of an Erdős–Rényi graph equipped with independent and identically distributed (i.i.d.) edge‐weights.

The exponential random graph model (ERGM) is a central object in the study of clustering properties in social networks as well as canonical ensembles in statistical physics. Despite some breakthrough works in the mathematical understanding of ERGM, most notably by Bhamidi, Bresler, and Sly [Ann. Appl. Probab. 21 (2011), pp. 2146–2170] through the analysis of a natural Heat-bath Glauber dynamics, and by Chatterjee and Diaconis [Ann. Statist. 41 (2013), pp. 2428–2461; Eldan [Geom. Funct. Anal. 28

This paper presents a low-noise potentiostat readout circuit with a chopper fully differential difference amplifier (FDDA) for glucose monitoring. Glucose monitoring is necessary for the early diagnosis of diabetes complications and for health management. Ammeter electrochemical sensors are widely used for glucose detection, and in general, a three-electrode structure of a reference electrode (RE), a counter electrode (CE), and a working electrode (WE) is implemented with a potentiostat structur

In this paper, low-noise incremental delta–sigma analog front end (AFE) integrated circuit (IC) for capacitive microsensors is presented. A conventional capacitance-to-digital converter (CDC) mainly uses a multi-stage capacitive sensing amplified stage (CSA) and analog-to-digital converters. The multi-stage CSA is not suitable for application in various Internet of things (IoT) devices that require low power because the power consumption of the analog front-end circuit increases in proportion to