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Image-based 3D reconstruction is not only useful for reconstructing visually realistic 3D flames, but it also deepens our understanding of flame physical nature. In this paper, we focus on the capturing and reusing of 3D temperature fields. A novel method is proposed to reconstruct and edit 3D temperature filed for combustion flame. Firstly, a multi-view imaging system is designed to capture the color...
This paper described the inherent mechanism of 500kV breaker protection operation. Analyzed the breaker protection action sequence based on the relay protection equipment action report and fault wave in chart recorder. Conducted the fault replay experiment on the logic of software and circuit configuration about communication triple trip. The results show that relay contacts blocking is the primary...
This study examines factors that determine the propensity of product innovation of entrepreneurial firms in ICT sector. These factors include R&D, founding team characteristics, education level of employees, environment, networking activities, adaptability to customer needs, and environment. Our Logit model shows that except environment, all of these variables have direct significant effects on...
A novel charge pump with variable frequency modulation (VFM) is proposed in this paper. To provide base for its design and improvement, detailed models for VFM charge pump are derived. And it is successfully implemented for the charge pump to introduce a voltage controlled oscillator (VCO) to control the switching frequency, which results in its high efficiency and low ripple output both at high load...
A CMOS bandgap reference (BGR) capable of operating at supply voltage of 0.9V was proposed in this paper. To guarantee its normal operation at ultra low supply voltage, the substrate bias techniques is used to reduce the threshold voltage. Meanwhile, an amplifier biased by subthreshold current is designed. This circuit is designed in tsmc 0.35μm CMOS technology. An average reference voltage of 658mV...
This paper presents a capacitor current based adaptive hysteresis controlled DC-DC converter. This controller avoids wide range frequency band filter or complicated compensation. Based on that capacitor current reflects the load current directly and fast, the proposed system uses a simple analog differentiator to sense the voltage capacitor current. Meanwhile, a PI compensation loop is added to improve...
This paper presents a power supply module (PSM) for SoCs (system on chip). This module, which is based on an improved LDO, has a wide input range and switchable power path. The proposed PSM can output a steady voltage of 6v as input voltage varies between 5.7 V-30 V, with a max error of 4.3%. It also provides a flexible power path. The SoCs will be supplied by either internal LDO or external power...
A Dual-mode clock generator based on a PLL(phase locked Loop)was proposed. The circuit, which provides 400 KHz internal fixed frequency mode and external input mode with a phase-lockable frequency range from 400 KHz to 2 MHz, is applicable to SMPS (Switching Mode Power Supply) controller IC to optimize its performance. A novel oscillation generator for low frequency application is introduced. The...
A universal protection controller for Li-ion battery charger is proposed in this paper. First, an in-depth analysis on Li-ion battery charger protection has been made, then a detailed system description was given, and finally test results were presented. This IC provides battery thermal protection, due time termination, bad cell detection, automatic recharge and state indication, which are usually...
A single-inductor dual-output (SIDO) buck converter controller is presented, which operates in self-adapted pseudo-continuous-conduction-mode (PCCM) with adjustable dc current levels. Freewheel switching control has been introduced to realize large load current with smaller current ripple, while cross regulation can be minimized. Furthermore, the dc current level of subconverters can be adjusted according...
A high-side current sense amplifier with wide input common mode range (ICMR) is proposed. To improve the accuracy of signal transfer, a common base structure is introduced to realize the control to bias currents. And a high accurate current mirror is used to enhance the gain precision. In addition, a common emitter and common source class AB amplifier topology is proposed to provide a rail-to-rail...
This paper presents an approach to design a high performance compensation loop for a photovoltaic system based on constant voltage (CV) maximum power point tracking (MPPT) method, which is quite different from that of common DC/DC converter. The dynamic model of the power module, which is implemented by a Buck converter, is established using switch average model. Based on the analysis of the dynamic...
A pulse width modulation (PWM) controller chip for LED driver was presented in this paper. The controller features two major operation modes, current feedback mode and constant current mode, so as to applicable to almost all DC-DC converter topologies such like buck, boost, buck-boost, flyback and SEPIC. A special error amplifier, which is composed of two sub-modules and a mode selector, was introduced...
Considering that the output voltage of battery will decline during its use, a four-switch buck-boost converter was proposed, which could provide stable output voltage over a wide voltage range of battery so as to extend the use time of battery and enhance its use efficiency. To improve the efficiency, the converter is designed to operate in multiple modes, which controlled by different strategies...
In order to increase the efficiency of portable devices powered by lithium-ion battery, a high efficiency multi-mode buck-boost controller IC is proposed in this paper. By applying a cascade buck-boost prototype, it not only realizes seamless transition between step up and down functions, but also achieves high efficiency over the entire load range by introducing BURST mode operation. System design...
The better efficiency means less heat dissipation and longer battery lifetime in wireless communication products and other portable systems powered by batteries. Therefore, the power management system with high efficiency is of great importance. As a solution, a green mode SMPS (switch mode power supply) buck regulator is proposed in this paper. Its efficiency is enhanced by so called multi-mode operation,...
To solve the excessive compensation problem that affects the performances of the peak current mode (PCM) controlled converter system, a novel slope compensation circuit named piecewise linear slope compensation was proposed, which provides compensation signals with different slopes according to different duty cycles. The design principles were introduced and the practical circuit was composed and...
To increase the efficiency of the SMPS (Switch Mode Power Supply) over the whole load range, a novel power supply module with low power consumption for multi-mode application was presented. The main modules constituting it include UVLO, Digital Power, Regulators (a 5 V regulator and a 4.3 V regulator) and REFOK. Especially, a control strategy was proposed to achieve its low power operation. The module...
Current-sharing techniques used in low- voltage high-current multi-phase voltage regulator module (VRM) were analyzed and discussed in detail. Analyzing the advantages and disadvantages of the current mode and voltage mode current sharing techniques respectively, a novel approach was proposed, which possess advantage of desired output voltage and supply voltage. A complete analysis and design method...
A four-stage BiCMOS operational amplifier with a quiescent current-controlled class AB output stage was presented. Double nested Miller compensation was taken to improve the stability. Either single or double power supplies were available for the amplifier and the voltage could be as low as 2 V. The quiescent output current under 5 V supply voltage was about 8 muA. With a load of 60 pF and 25 kOmega,...
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