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A discrete wavelet packet transform hardware design based on frame-partitioned architecture is presented in this paper. In the design of the processor, a kind of optimization technique of memory-the same address operation is proposed, which can decrease the size of the memory and raise the hardware utility efficiency. A two-buffer structure memory system is evolved to meet the real time request of...
This paper presents a method of designing an on-chip debug support module based on an 8051 architecture microcontroller. It is implemented by embedding a hardware debug module named on-chip debugger (OCD) into an 8-bit high performance microcontroller. Thus, this MCU can do such debugging work as setting hardware breakpoint, single stepping, monitoring and modifying the internal registers, internal...
It is very important to detect the speech endpoints accurately in speech recognition. This paper presents an improved method of endpoints detection based on the product of energy and frequency. The method uses energy-frequency-value as threshold to detect endpoints of speech signal, and induces the upper limit of length threshold and the lower limit of length threshold of speech signal, so that the...
In this paper, a sub IV bandgap voltage reference (BGR) with resistive subdivision in CMOS technology is described. The proposed topology is based on the combination of two elements' voltages of opposite temperature coefficients. By using resistive subdivision methods, maximum input voltage of a p-channel input operational amplifier can be reduced and the problem of sub IV supply voltage is solved...
Subband adaptive filtering reduces computational complexity and improves convergence performance. Here three kinds of subband adaptive filters (SAF) are investigated. The basic structure is simply composed of subbands decomposition and adaptive filters with low computation power. Based on the basic one, the second structure added by cross-filters is to eliminate subbands aliasing. The last one is...
The typical current mode bandgap voltage circuit is built up by two currents, one is proportional to VBE across the base-emitter of the parasitic BJT in CMOS process, the other is proportional to VT. The negative temperature coefficient of the former term compensates the positive temperature coefficient of the latter. But the temperature dependence of VBE is not linear and therefore doesn't completely...
A non-linear parameterized model of a sub-mini helicopter is created. By linearizing the non-linear model in hover, a linear attitude motion model about physical parameters is derived. At last, subspace method based on its discrete state space model is introduced to conduct linear system identification experiments. The simulation results show that the method used can quite correctly identify linear...
In this paper, we present architecture, circuit implementation and integration issues of embedded smart systems on flexible substrates for future ubiquitous intelligent world. The work is exampled by several concepts of innovative, self-powered, long-range interconnected radio-frequency identification and sensor networks in warehouse and intelligent goods distribution systems. Two types of RFID concepts...
The results of a finite element computer modelling analysis of a micro-manufactured one-turn magnetic inductor using the software package ANSYS 10.0 are presented. The inductor is designed for a DC-DC converter used in microelectronic devices. It consists of a copper conductor with a rectangular cross-section plated with an insulation layer and a layer of magnetic core. The analysis has focused on...
A standard modeling method to represent conduction in motherboard (MB) for predicting a ball-grid array package temperature is developed. It is shown that discrete representation of individual copper and FR4 layers within MB rather than an effective block is needed for accurate thermal prediction. The MB signal layers consists of set of parallel copper traces and are represented by orthotropic layer...
Power and power density increase on the level of integrated circuit (IC) has been exploding following Moore's law for more than two decades (2003). Riding on the trend of IC density increase, densities on chassis enclosure as well as cabinet levels have also been increasing dramatically. A standard cabinet measuring approximately W610mm times H1880mm times D102mm that used to house only one or two...
This paper describes the thermal-mechanical solutions for a community personal computer (PC), which is developed for rural Indian communities where the harsh living environment always poses the reliability challenge to maintain a conventional personal computer. The thermal-mechanical solution for micro-flip chip ball grid array (FCBGA) packaged CPU is presented and followed by the system level thermal,...
With the development of IC industry, system-on-chip becomes more and more complicated. Some big systems such as machine vision system require a great deal of operation, which could not be implemented well by only one processor. This paper presents an asymmetry architecture (1 master and 3 slaves) of multiprocessor SoC (MPSoC), and gives an example of its application on the machine vision system to...
Causality check and enforcement is practically important to the performance evaluation for interconnects based on time domain simulation. In this paper one causality check method based on minimum-phase and all-pass decomposition is proposed. Compared with conventional time domain approach, uncertainties from Gibbs error are bypassed. In contrast with conventional frequency domain methods, this method...
Energy for deformation, metamorphism and interconnection of metals, is mainly from high frequency pressure/shear loads via a PZT transducer assembly. Dynamical characteristics of PZT actuated transducer assembly are the key to reliable fine pitch bonding and basic understanding of metal interconnection. By using high frequency recording electronics devices and a powerful Polytec laser Doppler vibrometer,...
Vibration in the end of transducer affects the quality of fine pitch thermosonic bonding. Based on the experimental data acquired by laser Doppler vibrometer, vibration coupling along the different directions is analyzed. The bonding tool on/off test was performed to determine the bonding tool's effect on the transducer vibration. This work can be used for tool length selection for the better performance
Dynamical characteristics of transducer are important for ultrasonic bonding quality. The admittance curves of transducer were studied, by tool on/off test and clamping tightness changing test. The model of equivalent circuit is used for parameter analysis, based on admittance circle of the transducer. The results show that additive mass of bonding tool and clamp tightness may not affect resonance...
Thermosonic flip chip (TSFC) was performed and studied under the pressure constraint pattern, in which the flip chip is restricted by bonding force. Effects of bonding parameters on bonding strength were studied. Results show that bonding force and ultrasonic power have primary effects on bonding strength. The bonding strength is related to ultrasonic energy used in bonding interface, moderate energy...
Due to fine pitch BGA chips, acquiring high quality joints without detrimental effects on other components of chip needs accurate alignment of the unit in packaging technique. We developed an integrated laser-soldering system which combines a computer vision. Based on the analysis of experimental data, we find that lens distortions and assembly angular errors of X-Y stage play a distinct role in introducing...
With the background of SMT products manufacturing enterprises, we have probed into the manufacturing and managing mode of the SMT enterprises on the basis of the manufacturing execution system (MES) theory. According to the research on the manufacturing facilities and technological process of typical SMT manufacturing enterprises, some potential major problems are discovered in the application of...
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