A Native SPICE Implementation of Memristor Models for Simulation of Neuromorphic Analog Signal Processing Circuits

Since the memristor emerged as a programmable analog storage device, it has stimulated research on the design of analog/mixed-signal circuits with the memristor as the enabler of in-memory computation. Due to the difficulty in evaluating the circuit-level nonidealities of both memristors and CMOS devices, SPICE-accuracy simulation tools are necessary for perfecting the art of neuromorphic analog/mixed-signal circuit design. This article is dedicated to a native SPICE implementation of the memristor device models published in the open literature and develops case studies of applying such a circuit simulation with MOSFET models to study how device-level imperfections can make adversarial effects on the analog circuits that implement neuromorphic analog signal processing. Methods on memristor stamping in the framework of modified nodal analysis formulation are presented, and implementation results are reported. Furthermore, functional simulations on neuromorphic signal processing circuits including memristors and CMOS devices are carried out to validate the effectiveness of the native SPICE implementation of memristor models from the perspectives of simulation accuracy, efficiency, and convergence for large-scale simulation tasks.

Design of a high precision converter for multi-sensor information fusion

The converter is a measuring device and is used together with the displacement sensor. In view of the existing sensor transform device is susceptible to error and temperature drift effects acquisition accuracy is not high, we design a high precision transducer, multi-sensor information fusion for vehicle steering gear shaft angular displacement signal measurement, signal transformation and digital transmission. The converter has the characteristics of high precision, miniaturization and low cost. Multi-sensor information fusion high-precision converter adopts front-end signal amplifier circuit, following filter processing circuit and embedded software of microprocessor for online compensation to satisfy the requirements of high-precision transformation. The microcontroller is used as the main control chip to meet the requirements of 8-channel bipolar analog signal acquisition. Two 14-bit, 6-channel A/D chips are used to convert the bipolar analog signal in the range of ±10V, and the RS422 hardware interface circuit performs digital transmission according to the time sequence specified by the central programmer. The experimental results show that the conversion accuracy of the device can reach 0.06%, the digital signal transmission is stable, and it can be widely used in industrial production.

Sistem Pengaturan Pulse Width Modulation Motor Pada Robot Pembawa Makanan atau Minuman Menggunakan Joystick

Teknologi robotika kini sudah semakin berkembang pesat, hal ini ditunjukkan banyak sekali penggunaan teknologi robot yang digunakan dalam kehidupan sehari-hari untuk membantu pekerjaan manusia. Robot pengantar makanan atau minuman juga menjadi salah satu teknologi robotika yang kini semakin marak dikembangkan. Banyak peneliti yang sudah mulai mengembangkan robot sebagai alat pembantu pekerjaan manusia untuk pengantar makanan dan minuman. Pada robot tersebut, proses untuk mengatur kecepatan roda penggeraknya dapat menggunakan kontrol langsung atau kontrol tidak langsung. Pada penelitian ini, pengontrolan secara tidak langsung dilakukan menggunakan joystick untuk mengatur masukan pulse width modulation yang kemudian dikonversikan menjadi kecepatan robot. Pengaturan ini dibantu dengan mikrokontorller ATMEGA 328P sebagai alat untuk komputasi dan eksekusi jari program. Sehingga kecepatan robot dapat diatur dengan sempurna. Berdasarkan hasil pengujian diperoleh bahwa perubahan PWM awal pada saat robot dari kondisi diam menuju berjalan dengan perubahan kecepatan yang linier terhadap perubahan sinyal analog dari joystick, sehingga pergerakan robot lebih stabil. Nowdays, robotics was growing rapidly, it is widely used in everyday life to help human work. Food or beverage delivery robots are also one of the robotics technologies that are increasingly being developed today. Many developers has started to develop food or beverage delivery robots. In order to adjust the speed of the robots, we can use direct or indirect control. This study uses indirect control using joystick as a regulator of pulse width modulation which is converted to robot speed. Furthermore,, we used ATMEGA 328P microcontroller for computing and finger execution of the program. So that the speed of the robot can be adjusted perfectly. The result show that the initial PWM changes when the position of robot is rest to walking has linear change in speed to changes in the analog signal from the joystick, so that the robot's movement is more stable.

Audio module to capture, store and reproduce sound

This poster explains the design of an audio module, which is capable of capturing sound signals and storing them for later reproduction. The development platform is an embedded system (Beaglebone black), which has GPIO pins for user interaction. One of the objectives of the module is to keep production costs low, so the electronic components will be chosen taking quality criteria in operation as well as their cost. In the software component, the fdatool tool will be use to design the digital filter, getting the differences equation. It should be noted two major challenges that the development of this project has are the presence of noise in the analog signal and the sampling frequency with which the samples are taken to obtain the digital signal.

Discrete-to-analog signal conversion in human pluripotent stem cells

During development, state transitions are coordinated through changes in the identity of molecular regulators in a cell state- and dose specific manner. The ability to rationally engineer such functions in human pluripotent stem cells (hPSC) will enable numerous applications in regenerative medicine. Herein we report the generation of synthetic gene circuits that can detect a discrete cell state, and upon state detection, produce fine-tuned effector proteins in a programmable manner. Effectively, these gene circuits convert a discrete (digital-like) cell state into an analog signal by merging AND-like logic integration of endogenous miRNAs (classifiers) with a miRNA-mediated output fine-tuning technology (miSFITs). Using an automated miRNA identification and model-guided circuit optimization approach, we were able to produce robust cell state specific and graded output production in undifferentiated hPSC. We further finely controlled the levels of endogenous BMP4 secretion, which allowed us to document the effect of endogenous factor secretion in comparison to exogenous factor addition on early tissue development using the hPSC-derived gastruloid system. Our work provides the first demonstration of a discrete-to-analog signal conversion circuit operating in living hPSC, and a platform for customized cell state-specific control of desired physiological factors, laying the foundation for programming cell compositions in hPSC-derived tissues and beyond.

Digital Suppression of EMI-Induced Errors in a Baseband Acquisition Front-End including Off-the-Shelf, EMI-Sensitive Operational Amplifiers

In this paper, the susceptibility to Electromagnetic Interference (EMI) of an analog signal acquisition front-end (AFE) due to EMI distortion in opamp-based pre-conditioning amplifiers is addressed. More specifically, the possibility to correct EMI-induced errors in the digital domain by post-processing the acquired digital waveforms is discussed and experimentally demonstrated for the first time with reference to an AFE based on EMI-sensitive, off-the-shelf operational amplifiers mounted on a specific EMI test PCB. Extensive experimental characterization in the presence of continuous wave and amplitude modulated EMI reveals the superior immunity to EMI of the proposed AFE and the robustness of the approach.

2D materials–based homogeneous transistor-memory architecture for neuromorphic hardware

In neuromorphic hardware, peripheral circuits and memories based on heterogeneous devices are generally physically separated. Thus exploring homogeneous devices for these components is an important issue for improving module integration and resistance matching. Inspired by ferroelectric proximity effect on two-dimensional materials, we present a tungsten diselenide-on-LiNbO3 cascaded architecture as a basic device that functions as a nonlinear transistor, assisting the design of operational amplifiers for analog signal processing (ASP). It also functions as a nonvolatile memory cell, achieving memory operating (MO). Based on this homogeneous architecture, an analog signal processing-memory operating integrated system for binary classification and the design of ternary content-addressable memory were investigated for potential use in neuromorphic hardware.