An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management （PM） controller chips applied to telecommunication, automotive, lighting equipment, ...An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management （PM） controller chips applied to telecommunication, automotive, lighting equipment, etc., when high power supply voltage is needed. Accordingly,a new bandgap reference with a wide supply voltage range is proposed. Due to the improved structure,it features a high power supply rejection ratio （PSRR） and high temperature stability. In addition, an auxiliary micro-power reference is introduced to support the sleep mode of the PM chip and reduce its standby power consumption. The auxiliary reference provides bias currents in normal mode and a 1.28V reference voltage in sleep mode to replace the main reference and save power. Simulation results show that the reference provides a reference volt- age of 1.27V,which has a 3.5mV drift over the temperature range from -20 to 120~C and 56t^V deviation over a supply voltage range from 3 to 40V. The PSRR is higher than 100dB for frequency below 10kHz. The circuit was completed in 1.5tzm BCD （Bipolar-CMOS-DMOS） technology. The experimental results show that all main expectations are achieved.展开更多
In the past decade,several efforts around the world were started with the goal of introducing "smart metering" capabilities into the power grid.These efforts have spurred renewed interest in the design of ne...In the past decade,several efforts around the world were started with the goal of introducing "smart metering" capabilities into the power grid.These efforts have spurred renewed interest in the design of next generation Narrowband Power Line Communications(NB-PLC) transceivers.In the past few years,ITU-T and IEEE have standardized a family of next generation OFDM-based NB-PLC transceivers some of which are today being considered for massive deployments in Europe and Asia.This paper addresses the important role that PLC has not only for smart metering but also for many other Smart Grid applications,and also gives an overview of the main differences between these next generation NB-PLC standards.展开更多
Sensing structure of grid strip capacitors can be used in the design of capacitive micro-electromechanical system （MEMS） resonators, accelerometers etc. A grid strip structure consists of nonentirely overlap plates ...Sensing structure of grid strip capacitors can be used in the design of capacitive micro-electromechanical system （MEMS） resonators, accelerometers etc. A grid strip structure consists of nonentirely overlap plates so that the capacitor fringe effect cannot be neglected in the design. Electricmagnetic Finite Element Method （FEM） software ANSOFF-Maxwell is employed to analyze the fringe effect of a grid strip capacitor. The analysis includes capacitance changes with change of overlap length, overlap width, plate thickness, grid strip density etc. The results show that fringe effect leads to non-linear change of grid strip capacitance with the change of overlap length and width, that the capacitance increases with the increase of grid strip width and plate thickness, and that sensitivity can be improved through the increase of grid strip density in the condition of identical total overlap area, but linearity is reduced.展开更多
Broadband PLC （power line communication） technology is a main factor of the development of digital convergence in the indoor network. It uses the already existing power cable infrastructure for communication purpose...Broadband PLC （power line communication） technology is a main factor of the development of digital convergence in the indoor network. It uses the already existing power cable infrastructure for communication purposes. The EM （electromagnetic） field radiating from the cable could, however, disturb other communication systems, and thus should be evaluated. The MoM （method of moment） and the FEM （finite element method） have been studied to estimate the EVI field emitted from the power cable. However, the M oM is difficult to treat the dielectric material of the cable and the FEM is time consuming. This paperpresents a new approach to estimate the radiated EM fields caused by PLC sy stems from the CM current along the cable, based on the transmission line theory. The proposed model has the advantage of using the measured primary parameters of the cable. An experimental analysis of the EM radiation distribution is also presented. A comparison showed that the model results agree quite well with the measurements performed in this study.展开更多
For a strip transmission line shielded by rectangular walls, the Green抯 function is helpful to construct the variation expression of the electrostatic energy. Thomson theorem is employed to determine the charge distr...For a strip transmission line shielded by rectangular walls, the Green抯 function is helpful to construct the variation expression of the electrostatic energy. Thomson theorem is employed to determine the charge distribution on the strip. The electrostatic force on each side of the rectangular shield wall is achieved by using the principle of virtual work. The result is easy to be obtained by computerized calculation.展开更多
With a live wire, line impedance could be measured by means of only passive elements such as inductors or resistors, whose techniques are well known. However, as the voltage and current used for the measurement are in...With a live wire, line impedance could be measured by means of only passive elements such as inductors or resistors, whose techniques are well known. However, as the voltage and current used for the measurement are increased, the size of the inductor or resistor being used also needs to be increased, so it would be virtually impossible to make an accurate measurement. Because of this, the authors have developed a novel measurement method for line impedance using LC resonance, which the authors describe first place. In the second place, the authors propose another line impedance. The novel method is that the rectangular wave with minimum voltage is injected into the distribution line system. By means of this method, the line capacitance and the line inductance can be measured. These proposals are confirmed by the simulation or experiment. Finally, the frequency response analysis method is to be examined, whose mechanism and results are to be presented and discussed.展开更多
文摘An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management （PM） controller chips applied to telecommunication, automotive, lighting equipment, etc., when high power supply voltage is needed. Accordingly,a new bandgap reference with a wide supply voltage range is proposed. Due to the improved structure,it features a high power supply rejection ratio （PSRR） and high temperature stability. In addition, an auxiliary micro-power reference is introduced to support the sleep mode of the PM chip and reduce its standby power consumption. The auxiliary reference provides bias currents in normal mode and a 1.28V reference voltage in sleep mode to replace the main reference and save power. Simulation results show that the reference provides a reference volt- age of 1.27V,which has a 3.5mV drift over the temperature range from -20 to 120~C and 56t^V deviation over a supply voltage range from 3 to 40V. The PSRR is higher than 100dB for frequency below 10kHz. The circuit was completed in 1.5tzm BCD （Bipolar-CMOS-DMOS） technology. The experimental results show that all main expectations are achieved.
文摘In the past decade,several efforts around the world were started with the goal of introducing "smart metering" capabilities into the power grid.These efforts have spurred renewed interest in the design of next generation Narrowband Power Line Communications(NB-PLC) transceivers.In the past few years,ITU-T and IEEE have standardized a family of next generation OFDM-based NB-PLC transceivers some of which are today being considered for massive deployments in Europe and Asia.This paper addresses the important role that PLC has not only for smart metering but also for many other Smart Grid applications,and also gives an overview of the main differences between these next generation NB-PLC standards.
基金Supported by the National Natural Science Foundation of China （ No. 60903195 ） and the Key Technological Problems Tackling Project of Wuhan （No. 200750499172）.
文摘Sensing structure of grid strip capacitors can be used in the design of capacitive micro-electromechanical system （MEMS） resonators, accelerometers etc. A grid strip structure consists of nonentirely overlap plates so that the capacitor fringe effect cannot be neglected in the design. Electricmagnetic Finite Element Method （FEM） software ANSOFF-Maxwell is employed to analyze the fringe effect of a grid strip capacitor. The analysis includes capacitance changes with change of overlap length, overlap width, plate thickness, grid strip density etc. The results show that fringe effect leads to non-linear change of grid strip capacitance with the change of overlap length and width, that the capacitance increases with the increase of grid strip width and plate thickness, and that sensitivity can be improved through the increase of grid strip density in the condition of identical total overlap area, but linearity is reduced.
文摘Broadband PLC （power line communication） technology is a main factor of the development of digital convergence in the indoor network. It uses the already existing power cable infrastructure for communication purposes. The EM （electromagnetic） field radiating from the cable could, however, disturb other communication systems, and thus should be evaluated. The MoM （method of moment） and the FEM （finite element method） have been studied to estimate the EVI field emitted from the power cable. However, the M oM is difficult to treat the dielectric material of the cable and the FEM is time consuming. This paperpresents a new approach to estimate the radiated EM fields caused by PLC sy stems from the CM current along the cable, based on the transmission line theory. The proposed model has the advantage of using the measured primary parameters of the cable. An experimental analysis of the EM radiation distribution is also presented. A comparison showed that the model results agree quite well with the measurements performed in this study.
基金Funded by the Key Research Foundation of Sichuan Education Commission(No. 2002A046 )
文摘For a strip transmission line shielded by rectangular walls, the Green抯 function is helpful to construct the variation expression of the electrostatic energy. Thomson theorem is employed to determine the charge distribution on the strip. The electrostatic force on each side of the rectangular shield wall is achieved by using the principle of virtual work. The result is easy to be obtained by computerized calculation.
文摘With a live wire, line impedance could be measured by means of only passive elements such as inductors or resistors, whose techniques are well known. However, as the voltage and current used for the measurement are increased, the size of the inductor or resistor being used also needs to be increased, so it would be virtually impossible to make an accurate measurement. Because of this, the authors have developed a novel measurement method for line impedance using LC resonance, which the authors describe first place. In the second place, the authors propose another line impedance. The novel method is that the rectangular wave with minimum voltage is injected into the distribution line system. By means of this method, the line capacitance and the line inductance can be measured. These proposals are confirmed by the simulation or experiment. Finally, the frequency response analysis method is to be examined, whose mechanism and results are to be presented and discussed.
