An improved high-resolution current-mode sorter is presented.Its structure complexity is O(N),which is crucial to the expansion of its size,and its dynamic range is large.Only one clock signal and one reset signal are...An improved high-resolution current-mode sorter is presented.Its structure complexity is O(N),which is crucial to the expansion of its size,and its dynamic range is large.Only one clock signal and one reset signal are needed.No biasing signal is required.The operation point is constructed according to the input current,so it is self-adaptive,which is very important for an all-purpose component.In average value circuit,subtraction circuit,Winner-Take-All(WTA) circuit and control circuit,it has good performance even at a large input current.This sorter has high precision,high resolution and low power,as has been proved via HSPICE simulation.It can be implemented in the standard digital CMOS technology and widely used in many fields,so it is of great value in applications.展开更多
A novel matching cell circuitry using charge transfer circuit technique for high precision correlation calculation is presented.The cell calculates the absolute value of the difference between two analog input volt...A novel matching cell circuitry using charge transfer circuit technique for high precision correlation calculation is presented.The cell calculates the absolute value of the difference between two analog input voltages and amplifies the result.Amplification gain can be designed by the capacitance size in the cell and threshold voltage mismatch can be canceled automatically,thus high precision operation of the circuit is achieved.The circuit can be operated with low power dissipation of about 12μW at a frequency of 50MHz.Because of its simple structure and small silicon area,the matching cell is suitable to realize the correlation dealing with many template vectors that have many elements in a chip.展开更多
UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable ti...UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable timer based on the principle of ramp generators is described in this paper. The counting range of the timer is up to 16 bits, the timing precision is 8 ps, and the equivalent sampling rate is up to 50G Hz. No other identical product has been reported so far. This timer was successfully used in the data acquisition system for geological radar signals developed by us.展开更多
A novel topology low-voltage high precision current reference based on subthreshold Metal-Oxide-Semiconductor Field Effect Transistors （MOSFETs） is presented. The circuit achieves a temperature-independent reference...A novel topology low-voltage high precision current reference based on subthreshold Metal-Oxide-Semiconductor Field Effect Transistors （MOSFETs） is presented. The circuit achieves a temperature-independent reference current by a proper combination current of two first-order temperature-compensation current references, which exploit the temperature characteristics of integrated poly2 resistors and the 1- V transconductance characteristics of MOSFET operating in the subthreshold region. The circuit, designed with the 1 st silicon 0.35 μm standard CMOS logic process technology, exhibits a stable current of about 2.25 μA with much low temperature coefficient of 3 × 10^-4μA/℃ in the temperature range of-40-150 ℃ at 1 V supply voltage, and also achieves a better power supply rejection ratio （PSRR） over a broad frequency. The PSRR is about -78 dB at DC and remains -42 dB at the frequency higher than 10 MHz. The maximal process error is about 6,7% based on the Monte Carlo simulation. So it has good process compatibility.展开更多
With the increasing necessities for reliable printed circuit board(PCB) product, there has been a considerable demand for high speed and high precision vision positioning system. To locate a rectangular lead component...With the increasing necessities for reliable printed circuit board(PCB) product, there has been a considerable demand for high speed and high precision vision positioning system. To locate a rectangular lead component with high accuracy and reliability, a new visual positioning method was introduced. Considering the limitations of Ghosal sub-pixel edge detection algorithm, an improved algorithm was proposed, in which Harris corner features were used to coarsely detect the edge points and Zernike moments were adopted to accurately detect the edge points. Besides, two formulas were developed to determine the edge intersections whose sub-pixel coordinates were calculated with bilinear interpolation and conjugate gradient method. The last experimental results show that the proposed method can detect the deflection and offset, and the detection errors are less than 0.04° and 0.02 pixels.展开更多
Development in industry is asking for improved resolution and higher accuracy in dimensional metrology. In this paper,we proposed a control displacement method based on a polarization ellipsometirc interferometer and ...Development in industry is asking for improved resolution and higher accuracy in dimensional metrology. In this paper,we proposed a control displacement method based on a polarization ellipsometirc interferometer and phase-locked loop technique. The proposed principle was set up. The experimental results of step and step displacements with a step value of 5 nm were presented. We also analyzed the resolution,the potential minimal displacement of the established system. The results show that the position error induced by the ellipticty deviation of the light beam becomes negligible thanks to our signal processing circuit with high-order filter. This method could be useful for many applications in nano dimensional metrology and semiconductor industry.展开更多
文摘An improved high-resolution current-mode sorter is presented.Its structure complexity is O(N),which is crucial to the expansion of its size,and its dynamic range is large.Only one clock signal and one reset signal are needed.No biasing signal is required.The operation point is constructed according to the input current,so it is self-adaptive,which is very important for an all-purpose component.In average value circuit,subtraction circuit,Winner-Take-All(WTA) circuit and control circuit,it has good performance even at a large input current.This sorter has high precision,high resolution and low power,as has been proved via HSPICE simulation.It can be implemented in the standard digital CMOS technology and widely used in many fields,so it is of great value in applications.
文摘A novel matching cell circuitry using charge transfer circuit technique for high precision correlation calculation is presented.The cell calculates the absolute value of the difference between two analog input voltages and amplifies the result.Amplification gain can be designed by the capacitance size in the cell and threshold voltage mismatch can be canceled automatically,thus high precision operation of the circuit is achieved.The circuit can be operated with low power dissipation of about 12μW at a frequency of 50MHz.Because of its simple structure and small silicon area,the matching cell is suitable to realize the correlation dealing with many template vectors that have many elements in a chip.
基金This research is sponsored by National Natural Science Foundation of China,Special Fund of Scientific Instruments:The studyand development of flameproof ground penetrating radar (50127402).
文摘UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable timer based on the principle of ramp generators is described in this paper. The counting range of the timer is up to 16 bits, the timing precision is 8 ps, and the equivalent sampling rate is up to 50G Hz. No other identical product has been reported so far. This timer was successfully used in the data acquisition system for geological radar signals developed by us.
文摘A novel topology low-voltage high precision current reference based on subthreshold Metal-Oxide-Semiconductor Field Effect Transistors （MOSFETs） is presented. The circuit achieves a temperature-independent reference current by a proper combination current of two first-order temperature-compensation current references, which exploit the temperature characteristics of integrated poly2 resistors and the 1- V transconductance characteristics of MOSFET operating in the subthreshold region. The circuit, designed with the 1 st silicon 0.35 μm standard CMOS logic process technology, exhibits a stable current of about 2.25 μA with much low temperature coefficient of 3 × 10^-4μA/℃ in the temperature range of-40-150 ℃ at 1 V supply voltage, and also achieves a better power supply rejection ratio （PSRR） over a broad frequency. The PSRR is about -78 dB at DC and remains -42 dB at the frequency higher than 10 MHz. The maximal process error is about 6,7% based on the Monte Carlo simulation. So it has good process compatibility.
基金Project(51175242)supported by the National Natural Science Foundation of ChinaProject(BA2012031)supported by the Jiangsu Province Science and Technology Foundation of China
文摘With the increasing necessities for reliable printed circuit board(PCB) product, there has been a considerable demand for high speed and high precision vision positioning system. To locate a rectangular lead component with high accuracy and reliability, a new visual positioning method was introduced. Considering the limitations of Ghosal sub-pixel edge detection algorithm, an improved algorithm was proposed, in which Harris corner features were used to coarsely detect the edge points and Zernike moments were adopted to accurately detect the edge points. Besides, two formulas were developed to determine the edge intersections whose sub-pixel coordinates were calculated with bilinear interpolation and conjugate gradient method. The last experimental results show that the proposed method can detect the deflection and offset, and the detection errors are less than 0.04° and 0.02 pixels.
基金supported by the National Natural Science Foundation of China (Grant No.50905170)
文摘Development in industry is asking for improved resolution and higher accuracy in dimensional metrology. In this paper,we proposed a control displacement method based on a polarization ellipsometirc interferometer and phase-locked loop technique. The proposed principle was set up. The experimental results of step and step displacements with a step value of 5 nm were presented. We also analyzed the resolution,the potential minimal displacement of the established system. The results show that the position error induced by the ellipticty deviation of the light beam becomes negligible thanks to our signal processing circuit with high-order filter. This method could be useful for many applications in nano dimensional metrology and semiconductor industry.
