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Full-Text Articles in Engineering
Parallel Recording Of Neurotransmitters Release From Chromaffin Cells Using A 10 X 10 Cmos Ic Potentiostat Array With On-Chip Working Electrodes, Brian Kim, Adam Herbst, Sung Kim, Bradley Minch, Manfred Lindau
Parallel Recording Of Neurotransmitters Release From Chromaffin Cells Using A 10 X 10 Cmos Ic Potentiostat Array With On-Chip Working Electrodes, Brian Kim, Adam Herbst, Sung Kim, Bradley Minch, Manfred Lindau
Bradley Minch
Neurotransmitter release is modulated by many drugs and molecular manipulations. We present an active CMOS-based electrochemical biosensor array with high throughput capability (100 electrodes) for on-chip amperometric measurement of neurotransmitter release. The high-throughput of the biosensor array will accelerate the data collection needed to determine statistical significance of changes produced under varying conditions, from several weeks to a few hours. The biosensor is designed and fabricated using a combination of CMOS integrated circuit (IC) technology and a photolithography process to incorporate platinum working electrodes on-chip. We demonstrate the operation of an electrode array with integrated high-gain potentiostats and output time-division …
An Autozeroing Floating-Gate Amplifier, Paul Hasler, Bradley Minch, Chris Diorio
An Autozeroing Floating-Gate Amplifier, Paul Hasler, Bradley Minch, Chris Diorio
Bradley Minch
We have developed a bandpass floating-gate amplifier that uses tunneling and pFET hot-electron injection to set its dc operating point adaptively. Because the hot-electron injection is an inherent part of the pFET's behavior, we obtain this adaptation with no additional circuitry. Because the gate currents are small, the circuit exhibits a high-pass characteristic with a cutoff frequency less than 1 Hz. The high-frequency cutoff is controlled electronically, as is done in continuous-time filters. We have derived analytical models that completely characterize the amplifier and that are in good agreement with experimental data for a wide range of operating conditions and …
Multiple-Input Translinear Element Networks, Bradley Minch, Paul Hasler, Chris Diorio
Multiple-Input Translinear Element Networks, Bradley Minch, Paul Hasler, Chris Diorio
Bradley Minch
We describe a new class of translinear circuits that accurately embody product-of-power-law relationships in the current signal domain. We call such circuits multiple-input translinear element (MITE) networks. A MITE is a circuit element, which we defined recently that produces an output current that is exponential in a weighted sum of its input voltages. We describe intuitively the basic operation of MITE networks and provide a systematic matrix technique for analyzing the nonlinear relationships implemented by any given circuit. We also show experimental data from three MITE networks that were fabricated in a 1.2-μm double-poly CMOS process.
Synthesis Of Static And Dynamic Multiple-Input Translinear Element Networks, Bradley Minch
Synthesis Of Static And Dynamic Multiple-Input Translinear Element Networks, Bradley Minch
Bradley Minch
In this paper, we discuss the process of synthesizing static and dynamic multiple-input translinear element (MITE) networks systematically from high-level descriptions given in the time domain, in terms of static polynomial constraints and algebraic differential equations. We provide several examples, illustrating the process for both static and dynamic system constraints. Although our examples will all involve MITE networks, the early steps of the synthesis process are equally applicable to the synthesis of static and dynamic translinear-loop circuits.
Integration Of Chemical Sensing And Electrowetting Actuation On Chemoreceptive Neuron Mos (Cνmos) Transistors, Nick Shen, Zengtao Liu, Blake Jacquot, Bradley Minch, Edwin Kan
Integration Of Chemical Sensing And Electrowetting Actuation On Chemoreceptive Neuron Mos (Cνmos) Transistors, Nick Shen, Zengtao Liu, Blake Jacquot, Bradley Minch, Edwin Kan
Bradley Minch
An integration of chemical sensors and electrowetting actuators based on the chemoreceptive neuron MOS (CνMOS) transistors has brought forth a novel system-on-chip approach to the microfluidic system. The extended floating-gate structure of the CνMOS transistors enables monolithic sensing and actuating schemes. The sensors with generic chemical receptive areas have been characterized with various fluids, and have demonstrated a high sensitivity from the current differentiation and a large dynamic range from threshold-voltage shifts in sensing polar and electrolytic liquids. The actuators have illustrated valve functions based on contact-angle modification by nonvolatile charge injection into the channel wall. Electrochemical models for sensing …
A Second-Order Section Built From Autozeroing Floating-Gate Amplifiers, Paul Hasler, Theron Stanford, Bradley Minch
A Second-Order Section Built From Autozeroing Floating-Gate Amplifiers, Paul Hasler, Theron Stanford, Bradley Minch
Bradley Minch
We introduce the autozeroing floating-gate (AFGA) secondorder section. We built this second-order filter where the corner frequency and Q are electronically tunable based on a classic filter topology and principles of operational transconductance amplifiers. We built this second order filter using three AFGAs—our floating-gate amplifier that sets its operating point by the interaction of hot-electron injection and electron tunneling.
Hysteretic Threshold Logic And Quasi-Delay Insensitive Asynchronous Design, Mark Neidengard, Bradley Minch
Hysteretic Threshold Logic And Quasi-Delay Insensitive Asynchronous Design, Mark Neidengard, Bradley Minch
Bradley Minch
We introduce the class of hysteretic linear-threshold (HLT) logic functions as a novel extension of linear threshold logic, and prove their general applicability for constructing state-holding Boolean functions. We then demonstrate a fusion of HLT logic with the quasi-delay insensitive style of asynchronous circuit design, complete with logical design examples. Future research directions are also identified.
A Physical Compact Model Of Dg Mosfet For Mixed-Signal Circuit Applications - Part I: Model Description, Gen Pei, Weiping Ni, Abhishek Kammula, Bradley Minch, Edwin Kan
A Physical Compact Model Of Dg Mosfet For Mixed-Signal Circuit Applications - Part I: Model Description, Gen Pei, Weiping Ni, Abhishek Kammula, Bradley Minch, Edwin Kan
Bradley Minch
To use double-gate (DG) MOSFET for mixed-signal circuit applications, especially for circuits in which the two gates are independently driven, such as in the case of dynamic-threshold and fixed-potential-plane operations, physical compact models that are valid for all modes of operations are necessary for accurate design and analysis. Employing physically rigorous current-voltage (I-V) relationship in subthreshold and above-threshold regions as asymptotic cases, we have constructed a model that joins the two operating regions by using carrier-screening functions. We have included consistently source/drain series resistance, low drain-field mobility, and small-geometry effects of drain-induced barrier lowering (DIBL), MOS interface mobility, velocity saturation …
Charge-Based Chemical Sensors: A Neuromorphic Approach With Chemoreceptive Neuron Mos (Cvmos) Transistors, Nick Shen, Zengtao Liu, Chungho Lee, Bradley Minch, Edwin Kan
Charge-Based Chemical Sensors: A Neuromorphic Approach With Chemoreceptive Neuron Mos (Cvmos) Transistors, Nick Shen, Zengtao Liu, Chungho Lee, Bradley Minch, Edwin Kan
Bradley Minch
A novel chemoreceptive neuron MOS (CνMOS) transistor with an extended floating-gate structure has been designed with several individual features that significantly facilitate system integration of chemical sensing. We have fabricated CνMOS transistors with generic molecular receptive areas and have characterized them with various fluids. We use an insulating polymer layer to provide physical and electrical isolation for sample fluid delivery. Experimental results from these devices have demonstrated both high sensitivity via current differentiation and large dynamic range from threshold voltage shifts in sensing both polar and electrolytic liquids. We have established electrochemical models for both steady-state and transient analyses. Our …
Silicon Synaptic Adaptation Mechanisms For Homeostasis And Contrast Gain Control, Shih-Chii Liu, Bradley Minch
Silicon Synaptic Adaptation Mechanisms For Homeostasis And Contrast Gain Control, Shih-Chii Liu, Bradley Minch
Bradley Minch
We explore homeostasis in a silicon integrate-and-fire neuron. The neuron adapts its firing rate over time periods on the order of seconds or minutes so that it returns to its spontaneous firing rate after a sustained perturbation. Homeostasis is implemented via two schemes. One scheme looks at the presynaptic activity and adapts the synaptic weight depending on the presynaptic spiking rate. The second scheme adapts the synaptic"threshold" depending on the neuron's activity. The threshold is lowered if the neuron's activity decreases over a long time and is increased for prolonged increase in postsynaptic activity. The presynaptic adaptation mechanism models the …
Construction And Transformation Of Multiple-Input Translinear Element Networks, Bradley Minch
Construction And Transformation Of Multiple-Input Translinear Element Networks, Bradley Minch
Bradley Minch
We present a simple algorithmic procedure for constructing a multiple-input translinear element (MITE) network from a translinear-loop equation. We also give a number of MITE-network transformations that alter the structure of the MITE network without altering the translinear-loop equation that it embodies. The results that we establish in this paper serve as foundations for the synthesis of both static and dynamic MITE networks from high-level specifications.
Implementing The Lorenz Oscillator With Translinear Elements, Kofi Odame, Bradley Minch
Implementing The Lorenz Oscillator With Translinear Elements, Kofi Odame, Bradley Minch
Bradley Minch
Nonlinear processing is often more suitable than the traditional linear approach is for analyzing biological signals. Unfortunately, digital nonlinear operations are computationaly expensive. In contrast, a large variety of nonlinear operations can efficiently be implemented in analog electronics, operating at real-time speeds. The low level of accuracy generally associated with analog processing is not a concern in this scenario, as biological signals themselves typically have low signal-to-noise ratios. One challenge of analog processing is in its apparently- ad hoc design, and the fact that there is very little wide-spread knowledge of systematically implementing analog electronics to perform arbitrary nonlinear computations. …