Interface Circuit Design Research Articles

A mini I2C bus interface circuit design and its VLSI implementation

A mini I2C bus interface circuit design and its VLSI implementation

Design of an interface circuit system for mode-separation MEMS digital gyroscope

In this paper, a novel digital closed-loop interface circuit system of MEMS vibrating gyroscope is proposed, which includes driving, detection and quadrature circuits. Because of the high sensitivity and precision of the MEMS gyroscope, the interface circuit system is established under the condition of mode separation. The driving circuit of MEMS gyroscope adopts digital automatic gain control (AGC) to realize self-excitation closed-loop control, which makes the gyroscope system simple in structure and good in robustness. First, the working principle of the gyroscope’s sensitive structure is introduced and the system simulation model of the sensitive structure is developed. Second, a [Formula: see text] ADC and DAC with single-bit output are designed and the feasibility of the driving circuit design is verified by the system-level model. Third, the quadrature closed-loop correction circuit is designed to reduce the coupling of the quadrature component to the gyroscope detection circuit. The simulation results show that the quadrature correction loop can effectively reduce the influence of the quadrature coupling on the detection loop of MEMS gyroscope. Finally, the system-level model of the gyroscope is established by SIMULINK, the overall system performance of the gyroscope is analyzed, and the test system of MEMS gyroscope is built by field-programmable gate array (FPGA) and application specific integrated circuit (ASIC). The experiment verifies the feasibility of the digital interface circuit design, and the zero-bias instability of the gyroscope system is 1.0∘/h.

A Review of Piezoelectric Energy Harvesting: Materials, Design, and Readout Circuits

Mechanical vibrational energy, which is provided by continuous or discontinuous motion, is an infinite source of energy that may be found anywhere. This source may be utilized to generate electricity to replenish batteries or directly power electrical equipment thanks to energy harvesters. The new gadgets are based on the utilization of piezoelectric materials, which can transform vibrating mechanical energy into useable electrical energy owing to their intrinsic qualities. The purpose of this article is to highlight developments in three independent but closely connected multidisciplinary domains, starting with the piezoelectric materials and related manufacturing technologies related to the structure and specific application; the paper presents the state of the art of materials that possess the piezoelectric property, from classic inorganics such as PZT to lead-free materials, including biodegradable and biocompatible materials. The second domain is the choice of harvester structure, which allows the piezoelectric material to flex or deform while retaining mechanical dependability. Finally, developments in the design of electrical interface circuits for readout and storage of electrical energy given by piezoelectric to improve charge management efficiency are discussed.

Design of Interface Circuits and Lightweight PUF for TMR Sensors

The micro-magnetometers with high-resolution digital output are widely used in military and civilian fields. We proposed a novel high-precision interface circuit with optimized chopper technique and switched-capacitor modulator for tunneling magnetoresistance (TMR) sensors. This work also proposes a novel method to create lightweight physically unclonable function (PUF) by using existing TMR devices. The sigma-delta modulator converts the sensor signal into a robust digital output and maintain the signal-to-noise ratio (SNR) of the front-end circuit. We also take advantage of inherent variations of TMR sensors to generate PUF responses that are similarly unique and unclonable. The interface circuit is fabricated by 0.35μm CMOS process from Shanghai Huahong foundry. The active area of ASIC is only about 3 mm×2.7 mm. The interface circuit can achieve a SFDR of 120dB and a SNR of 98 dB at a sampling frequency of 200kHz. The TMR magnetometers were tested in an environment of three-layer magnetic shielding. Our proposed PUF is also tested in terms of uniqueness and reliability.

A method of aeronautical electrical interface circuit design and simulation analysis based on Saber

In this paper, the idea of model-based system engineering is adopted. For the aircraft’s electrical interface circuit, Saber software is used to carry out “device-circuit” modeling and simulation, and the corresponding hardware circuits are verified and compared. Simulation and hardware verification results show that the modeling method designed in this paper can better integrate the rapidity of modeling and the accuracy of the simulation. In order to deal with the “neck jam” problem, domestic components are widely used today. This study provides a solution for optimizing process design and improving the degree of digitalization and provides model support for Model Based Systems Engineering (MBSE) in China’s aviation field.

A Scheme for Distribution Automation Terminal Design Based on ESIM

To realize the operation monitoring and control of distribution network, improve the reliability of power supply and reduce the intensity of operation and maintenance, a design scheme of distribution automation terminal based on eSIM card is proposed. Based on the analysis of eSIM technology and its characteristics, the basic workflow of eSIM card is provided in combination with the remote configuration requirements of power system. Then the main control function and communication module design of the distribution network system are analyzed and explained in detail, with emphasis on the communication interface circuit and software design. The system also integrates AngularJS and SpringBoot to make the platform have the technical characteristics of separation of front and back stations and strong reliability. At the same time, the dial-up and positioning information are integrated into one module to realize real-time monitoring and control of the remote master station. The experimental analysis results show that the scheme has certain advantages in the reliability of distribution automation terminals and the simplification of operation and maintenance management, which increases the integration and functional diversity of power equipment.

Recent Advances in CMOS Electrochemical Biosensor Design for Microbial Monitoring: Review and Design Methodology.

Rapid, high-sensitivity, and real-time characterization of microorganisms plays a significant role in several areas, including clinical diagnosis, human healthcare, early detection of outbreaks, and the protection of living beings. Integrating microbiology and electrical engineering promises the development of low-cost, miniaturized, autonomous, and high-sensitivity sensors to quantify and characterize bacterial strains at various concentrations. Electrochemical-based biosensors are receiving particular attention in microbiological applications among the different biosensing devices. Several approaches have been adopted to design and fabricate cutting-edge, miniaturized, and portable electrochemical biosensors to track and monitor bacterial cultures in real time. These techniques differ in their sensing interface circuits and microelectrode fabrication. The goals of this review are (i) to summarize the current state of CMOS sensing circuit designs in label-free electrochemical biosensors for bacteria monitoring and (ii) to discuss the material and size of the electrodes used in electrochemical biosensors in microbiological applications. In this paper, we reviewed the latest and most advanced CMOS integrated interface circuits that have recently been used in electrochemical biosensors to identify and characterize bacteria species, such as impedance spectroscopy, capacitive, amperometry, and voltammetry, etc. In addition to the interface circuit design, other crucial factors, such as the material and scale of the electrodes, must be considered to increase the sensitivity of electrochemical biosensors. Surveying the literature in this field improves our knowledge about the impact of electrode designs and materials on sensing precision and will help future designers adapt, design, and fabricate appropriate electrode configurations based on their application. Thus, we summarized the conventional microelectrode designs and materials mainly employed in microbial sensors, including interdigitated electrodes (IDEs), microelectrode arrays (MEAs), paper, and carbon-based electrodes, etc.

A Design Support Tool Set for Interface Circuits Between Synchronous and Asynchronous Modules

In this paper, we propose a design support tool set for interface circuits between synchronous and asynchronous modules. To facilitate the design of interface circuits between synchronous and asynchronous modules, the proposed tool set generates interface circuits and design constraints based on a predefined communication scheme. In addition, the proposed tool set performs timing verification and delay adjustment to guarantee the operations of the generated interface circuits. In the experiment, we evaluated the latency and overhead of the generated interface circuits. The latency and handshake overhead of the interface circuits generated by the proposed tool set depend on the cycle time of the receiver module. In addition, we designed a system which consists of a synchronous RISC-V processor and an asynchronous multilayer perceptron (MLP) circuit using the proposed tool set. The energy consumption of the system was reduced by 34.0% compared with a system which uses a synchronous MLP circuit.

A Mode-Matched DRG Realized by Monolithic Integrated Interface Circuit Design

This article proposes a novel design method for the mode-matched disk resonator gyroscope (DRG) realized by the monolithic integrated interface circuit. The mode-mismatched dynamics model of DRG is simplified by introducing the analysis method of “slow” dynamics, the effect of mode mismatching is quantified, and the automatic mode-matched interface circuit is designed based on the analysis of the simplified model. The force-rebalance loop is designed based on a self-clock circuit that releases the chip from the dependence on external clocks, avoids the design of multipliers, analog-to-digital converters (ADCs), and digital-to-analog converters (DACs), and improves the integration of the chip. The highly integrated automatic mode-matching loop is realized by the designing of a quadrature loop and stiffness tuning loop on the basics of the mode-matching theory. The design method is applied to develop a monolithic integrated interface chip of DRG with an area of 4.2 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times4.3$ </tex-math></inline-formula> mm and power consumption of 90 mW. The DRG integrated circuit achieves the bias instability (BI) of 0.38°/h and the angle random walk (ARW) of 0.0354°/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\surd \text{h}$ </tex-math></inline-formula> within a full scale of ±300°/s, which provides a highly integrated circuit design scheme for DRG’s extensive application.

Piezoelectric Energy Harvesting at Circuit Resonance with Active Inductor (CRAI)

Background: Most of the proposed interface circuits use bulky inductors to enhance the key performance parameter i.e., power transfer efficiency. This sets constraints on the design of power conditioning circuitry for constrained IoT applications. Objective: To replace the bulky physical inductor with area optimized components suitable for integrated circuit realization with reduced silicon footprint for constrained applications like Internet-of-Things (IoT). Method: This paper presents the implementation of Circuit Resonance with Active Inductor (CRAI) technique based interface circuit design to deliver the maximum power generated from the Piezoelectric Energy (PEH) source to the load. Results: Compared to the conventional FWBR technique, the proposed CRAI technique improves ≈2X power delivered to the load. Conclusion: The proposed work presents an inductor-less interface circuit for PEH. An active inductor (gyrator) is used to induce ‘IP’ rejection at the PEH circuit resonant frequency to enhance the performance parameters. Since the proposed technique is based on active inductor, it can be easily fabricated in small integrated circuit (IC) packages, allowing integration with state-of-the-art constrained IoT applications. CRAI technique based on the rejection of ‘IP’ at the resonance using active inductor is first reported here. The proposed concept is non-adiabatic, but it could be used for constrained self-powered autonomous IoT applications and it could be of importance in guiding the design of new interface circuits for PEH.

Design of the digital interface circuit system for MEMS gyroscope

In this paper, a digital closed-loop measurement and control system of MEMS vibrating silicon gyro is proposed, which includes the sensitive structure model of gyro and the design of interface circuit. Because of the high sensitivity and precision of the MEMS gyroscope under the condition of modal matching, the measurement and control circuit is established under the condition of modal matching. The system uses automatic gain control (AGC) to control the amplitude of self-excited oscillation of the driving loop, which has the characteristics of simple and quick start. First, the working principle of gyro sensitive structure is introduced and an interface circuit with digital drive and detection mode is designed. Second, a high precision one-bit sigma-Delta ([Formula: see text] analog-to-digital converter (ADC) is designed, and the signal-to-noise ratio (SNR) of the modulator is 102.5 dB at 10 kHz bandwidth. Third, a nonlinear multiplier is used in the driving loop to realize fast self-excited start-up of gyro, and a proportional integral (PI) controller is used in the self-excited loop to realize stable oscillation. Finally, Simulink is used to simulate and verify the sensitive structure model and the measurement and control system. The nonlinearity of the gyroscope is tested by experiment, and the well measurement and control precision of the gyro interface circuit is verified.

Design of an Energy Harvesting Interface Circuit Consecutively Powering Two Loads

ABSTRACT This paper presents an energy harvesting interface circuit for a single ambient energy source that consecutively delivers power supply to two loads including one light load and one heavy load. The proposed circuit consists of a step-up converter, a temporary storage element (e.g. supercapacitor), two charge control circuits for the loads, and two power transistors. The converter receives low-voltage from the output of the energy source to charge the supercapacitor at the output of the converter to high voltage levels. The supercapacitor delivers energy to the light load through corresponding control circuit. Due to the light load, the generated energy by the energy source is greater than the required power by the load. This results in accumulating the surplus energy into the supercapacitor. Once the supercapacitor stores sufficient energy, the energy direction from the supercapacitor is shifted from the light load to the heavy load. Once the supercapacitor discharges to a voltage level where the heavy load stops to receive power supply, the energy direction will be toward to the light load again. The same powering pattern will be repeated over the time. As a result, these loads operate in burst mode. The proposed circuit, constructed with off-the-shelf components, regulates outputs to nearly 3.9 V, starts the operation from an input voltage as low as 0.1 V and achieves a peak efficiency of 73.29%. The proposed circuit provides the highest output power of 124.14 mW which is greater than prior IC work supports. Apart from the highest output power, the proposed circuit meets the goal of self-sustainability since there is no need of extra power source (e.g., battery) other than the ambient energy source.

A Bidirectional Energy Conversion Circuit Toward Multifunctional Piezoelectric Energy Harvesting and Vibration Excitation Purposes

Piezoelectric transducers provide a bidirectional channel for converting energy from mechanical form to electrical or in the opposite direction. Various applications were developed with either of these two energy-flow processes. For example, energy harvesters take advantage of the energy flow from mechanical to electrical domains, while vibration exciters utilize that from electrical to mechanical domains. However, few designs have integrated the bidirectional energy-flow processes in a single device in the past. Such an integration is beneficial to some multifunctional applications. The key obstacle of integrated bidirectional design results from the interface circuit design, rather than the transducer. This article makes a breakthrough by proposing a bidirectional energy conversion circuit (BECC) solution for the time-sharing energy harvesting and vibration exciting purpose. It is realized by developing a new control strategy on the synchronized triple bias-flip (S3BF) piezoelectric interface circuit, which was formerly used for energy harvesting enhancement. The control logic for energy harvesting and vibration exciting modes are discussed in detail. The time-sharing multi-functional ability is validated in experiments. It is the first time to realize a compact and integrated self-excitable energy harvester by using a single interface circuit. Experiments are carried out for validating the feasibility of the BECC toward future versatile engineering designs.

An inductorless piezoelectric energy harvesting interface circuit using gyrator induced voltage flip technique

PurposeThe purpose of this research paper is to explore the possibility to enhance the power transfer from piezoelectric energy harvester (PEH) source to the load. As the proposed gyrator-induced voltage flip technique (GIVFT) does not require bulky components such as physical inductors, it is easily realizable in small integrated circuits (IC) package thereby offering performance benefits, reducing area overhead and providing cost benefits for constrained self-powered autonomous Internet-of-Things (IoT) applications.Design/methodology/approachThis paper presents an inductorless interface circuit for PEH. The proposed technique is called GIVFT and is demonstrated using active elements. The authors use gyrator to induce voltage flip at the output side of PEH to enhance the charge extraction from PEH. The proposed technique uses the current-voltage (I-V) relationship of gyrator to get appropriate phasor response necessary to induce the voltage flip at the output of PEH to gain power transfer enhancement at the load.FindingsThe experimental results show the efficacy of the GIVFT realization for enhanced power extraction. The authors have compared their proposed design with popular earlier reported interface circuits. Experimentally measured performance improvement is 1.86×higher than the baseline comparison of full-wave bridge rectifier circuit. The authors demonstrated a voltage flip using GIVFT to gain power transfer improvement in piezoelectric energy harvesting.Originality/valueTo the best of the authors’ knowledge, pertaining to the field of PEH, this is the first reported GIVFT based on the I-V relationship of the gyrator. The proposed approach could be useful for constrained self-powered autonomous IoT applications, and it could be of importance in guiding the design of new interface circuits for PEH.

Complex event detection for commodity distribution Internet of Things model incorporating radio frequency identification and Wireless Sensor Network

This paper discusses the key technologies for the fusion of Radio Frequency Identification (RFID) technology and wireless sensor networks through a fusion approach; meanwhile, it addresses the problem of energy imbalance infusion networks. This paper introduces the network energy consumption calculation methods under direct transmission and minimum energy multi-hop routing protocols, and designs an improved network structure model to improve the communication scale. The RFID reading and writing system based on Zig Bee technology is developed, and focuses on the hardware interface circuit design of the fusion system, the development of compatible communication protocols, the anti-collision algorithm, and the transmission performance of the system under two outdoor environments. The design of the environmental collection terminal uses relevant sensors to collect the transport environment data in the carriage. And Wireless Sensor Network (WSN) combined with General Packet Radio Service (GPRS) technology realizes the function of the main aggregation node of wireless sensors. The method achieves data aggregation and data transmission, and the development of the application platform of the monitoring system uses software technology. Based on the browser/server (B/S) architecture, the development of the monitoring system is finally realized. Finally, the cold chain transportation simulation experiment was conducted to test the system, and the results showed that the hardware of the cold chain coordination monitoring system can work normally and the software design of the monitoring system can meet the basic requirements of the system for the third-party logistics enterprises. The efficiency of our results is improved by about 10% compared to other studies, and their accuracy is improved to a higher degree, which makes our model more practical.

Design and analysis of a waterproof capacitive touch key sensor interface circuit

Traditional mechanical keys are gradually replaced with touch keys. Capacitive touch keys have advantages in achieving higher sensitivity with a longer service life and lower cost. Hence, the capacitive touch key technology is widely used in consumer electronic products. In use of household electric appliances, such as electric kettle, induction cooker and exhaust hood, sometimes the water vapor would condense into visible moisture or even the water would splash out of the pot when overheated, which may lead to a falsely trigger of touch key. So, waterproof becomes a big challenge in household electric appliances. This paper analyzes how water affects capacitive touch key and proposes a waterproof capacitive touch key sensor interface circuit to overcome the challenge. Sensing of touch key capacitor would be influenced only when water covers more than two touch keys. Compensating channels working in certain strategy are used to decrease the influence of water. For the same water capacitor, the bigger threshold voltage, the bigger change of the counting number. A much smaller threshold voltage is better to further weak the effect of water. The circuit is implemented in a standard 110 nm CMOS process. The measured results show that the touch Signal to Noise and Water Disturb Ration (SNWDR) is 20.7 dB which proves that the proposed waterproof capacitive touch key sensor interface circuit is effective against water splash.

Design of fire alarm system of intelligent camera based on fuzzy recognition algorithm

Aiming at the problems of low fire detection accuracy and high false alarm rate of the current intelligent camera fire accident alarm system, a fire accident alarm system based on fuzzy recognition algorithm is designed. By analyzing the structural principle of the fire detection and alarm system, selecting the CO gas, temperature and smoke sensor selection, designing the corresponding fire signal detection circuit, and designing the single-chip system circuit, including the single-chip clock circuit, reset circuit, power supply circuit and A/D conversion circuit design, on the basis of in-depth study of the Bluetooth communication protocol structure, the hardware design of the serial interface circuit of the single-chip microcomputer, PC and Bluetooth module has been completed. The fuzzy recognition algorithm is used to set the input and output, establish the control rule table and reasoning relationship, generate the input and output rule table, preprocess the sensor signal, and finally output the fire alarm model through the fuzzy inference system, so as to realize the fire accident alarm of the intelligent camera. The experimental results show that the fire detection accuracy of the proposed method is high, and can effectively reduce the false alarm rate and false alarm rate of the system.

STM32-Based Intelligent Desk Lamp Design and Implementation

Table lamps have long been one of the necessities of people’s life and work, as they appear and are used very frequently in household lighting equipment. Table lamps provide the right amount of light for people to work and study in their daily lives. Compared with the general traditional desk lamp, intelligent desk lamps provide a more comfortable lighting environment for people to read, work and study. The paper firstly analyzes the system scheme of the intelligent desk lamp and completes the hardware selection, using STM32F103C8T6 as the main control, HR-SR501 module as the pyroelectric module of the intelligent desk lamp. HC-SR04 ultrasonic distance measures sensor for distance measurement. Bluetooth module HC-05 is the wireless control module of the lamp. Then the interface circuit design of each functional module is completed by drawing schematic diagram through Altium Designer. The program design of each function by drawing program flowchart is completed. The program is written through keil5. Finally, the automatic adjustment of lighting intensity, posture reminder, human infrared sensing and wireless control of the intelligent lamp are realized through a combination of hardware and software. Desk lamp has the advantages of simple operation, energy saving, sitting posture reminder, automatic dimming and wireless control, etc. Compared with the general traditional desk lamp, it solves the problems of traditional desk lamp control not simple enough, high energy consumption and being easy to cause visual fatigue or myopia; therefore, it has high application value and market value.

基于STM32的农业智能烤烟房温湿度控制仪的设计

The quality of tobacco baking is one of the important factors affecting the economic benefits of tobacco enterprises. Because of the low efficiency of traditional manual baking methods and the poor quality of tobacco, the economic benefits of tobacco enterprises and tobacco farmers are also greatly affected. In view of this, this research takes the temperature and humidity control as the research object, and proposes an agricultural intelligent tobacco house temperature and humidity controller based on STM32. Firstly, the general design scheme, hardware circuit design scheme and software design scheme of the control system are described, in which the human-machine interface circuit design of the hardware circuit design is emphatically analysed, and finally, the design of this research is applied The agricultural intelligent temperature and humidity controller measures the temperature and humidity of the flue-cured tobacco house, and verifies the control effect. The results show that the temperature control accuracy based on STM32 is significantly higher than that of traditional control method, which is conducive to the improvement of tobacco baking quality. It is hoped that this study can provide a significant reference for the research of temperature and humidity control in tobacco industry in China.

A Capacitive Pressure Sensor Interface IC with Wireless Power and Data Transfer.

This paper presents a capacitive pressure sensor interface circuit design in 180 nm XH018 CMOS technology for an implantable capacitive pressure sensor, which has a wireless power supply and wireless data transfer function. It integrates full-bridge rectifiers, shorting control switches, low-dropout regulators, bandgap references, analog front end, single slope analog to digital converter (ADC), I2C, and an RC oscillator. The low-dropout regulators regulate the wireless power supply coming from the rectifier and provide a stable and accurate 1.8 V DC voltage to other blocks. The capacitance of the pressure sensor is sampled to a discrete voltage by the analog front end. The single slope ADC converts the discrete voltage into 11 bits of digital data, which is then converted into 1 kbps serial data out by the I2C block. The “1” of serial data is modulated to a 500 kHz digital signal that is used to control the shorting switch for wireless data transfer via inductive back scatter. This capacitive pressure sensor interface IC has a resolution of 0.98 mmHg (1.4 fF), average total power consumption of 7.8 mW, and ±3.2% accuracy at the worst case under a −20 to 80 °C temperature range, which improves to ±0.86% when operated between 20 and 60 °C.