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1.
A new vision coordinate measuring system-single camera 3-D coordinate measuring system based on optical probe imaging is presented.A new idea in vision coordinate measurement is proposed.A linear model is deduced which can distinguish six freedom degrees of optical probe to realize coordinate measurement of the object surface.The effects of some factors on the resolution of the system are analyzed.The simulating experiments have shown that the system model is available.  相似文献   

2.
A10 bit 250 MS/s current-steering digital-to-analog converter is presented. Only standard Vv core de- vices are available for the sake of simplicity and low cost. In order to meet the INL performance, a Monte Carlo model is built to analyze the impact of mismatch on integral nonlinearity (INL) yield with both end-point line and best-fit line. A formula is derived for the relationship oflNL and output impedance. The relation of dynamic range and output impedance is also discussed. The double eentroid layout is adopted for the current source array in order to mitigate the effect of electrical, process, and temperature gradient. An adapted current mirror is used to over- come the gate leakage of the current source array, which cannot be ignored in the 65 nm GP CMOS process. The digital-to-analog converter occupies 0.06 mm2, and consumes 2.5 mW from a single 1.0 V supply at 250 MS/s.  相似文献   

3.
A 4224 MHz phase-locked loop(PLL) is implemented in 0.13μm CMOS technology.A dynamic phase frequency detector is employed to shorten the delay reset time so as to minimize the noise introduced by the charge pump.Dynamic mismatch of charge pump is considered.By balancing the switch signals of the charge pump,a good dynamic matching characteristic is achieved.A high-speed digital frequency divider with balanced input load is also designed to improve in-band phase noise performance.The 4224 MHz PLL achieves...  相似文献   

4.
Shunt resistance of solar cell must be monitored for large area solar cell manufactured with conventional process .A measuring method for the shunt resistance is derived from direct-current model.The shunt resistance of solar cell is obtained only by treating a part of Ⅰ-Ⅴdata.  相似文献   

5.
In this paper, a walking robot is established. The zero-moment point(ZMP) is used to stabilize the working robot. The kinematic model of the robot based on denavit-hartenberg(D-H) method is presented in this thesis. And then the dynamic model, based on Lagrange method, is built by simplifying the kinematic model of robot body. A kinematic simulation to the robotic system is achieved based on Adams. Driving torque of left ankle is calculated according to joint angle, angular velocity and angular acceleration. The validity of the dynamic model is testified by comparing with the result of simulation.  相似文献   

6.
This paper proposes a direct injection-locked frequency divider(ILFD) with a wide locking range in the Ka-band. A complementary cross-coupled architecture is used to enhance the overdriving voltage of the switch transistor so that the divider locking range is extended efficiently. New insights into the locking range and output power are proposed. A new method to analyze and optimize the injection sensitivity is presented and a layout technique to reduce the parasitics of the cross-coupled transistors is applied to decrease the frequency shift and the locking range degradation. The circuit is designed in a standard 90-nm CMOS process. The total locking range of the ILFD is 43.8% at 34.5 GHz with an incident power of –3.5 dBm. The divider IC consumes 3.6 mW of power at the supply voltage of 1.2 V. The chip area including the pads is 0.50.5 mm2.  相似文献   

7.
A high stability in-circuit reprogrammable technique control system for a capacitive MEMS accelerometer is presented. Modulation and demodulation are used to separate the signal from the low frequency noise. A low-noise low-offset charge integrator is employed in this circuit to implement a capacitance-to-voltage converter and minimize the noise and offset. The application-specific integrated circuit (ASIC) is fabricated in a 0.5 /μm one-ploy three-metal CMOS process. The measured results of the proposed circuit show that the noise floor of the ASIC is -116 dBV, the sensitivity of the accelerometer is 66 mV/g with a nonlinearity of 0.5%. The chip occupies 3.5×2.5 mm2 and the current is 3.5 mA.  相似文献   

8.
终端式MEMS微波功率传感器的热时间常数研究   总被引:1,自引:1,他引:0  
许映林  廖小平 《半导体学报》2009,30(10):104006-4
A terminating type MEMS microwave power sensor based on the Seebeck effect and compatible with the GaAs MMIC process is presented.An electrothermal model is introduced to simulate the thermal time constant. An analytical result,about 160 ms,of the thermal time constant from the non-stationary Fourier heat equations for the structure of the sensor is also given.The sensor measures the microwave power jumping from 15 to 20 dBm at a constant frequency 15 GHz,and the experimental thermal time constant result is 180 ms.The frequency is also changed from 20 to 10 GHz with a constant power 20 dBm,and the result is also 180 ms.Compared with the analytical and experimental results,the model is verified.  相似文献   

9.
一种用于液晶显示的高转换速率恒定跨导运算放大器   总被引:1,自引:1,他引:0  
To drive the backplane of a liquid crystal display device and achieve different kinds of grey levels, a high-slew-rate operational amplifier with constant-gin input stage is presented. A Zener-diode structure is inserted between the tails of the complementary input pairs to keep the grn of the input stage constant. A novel slew rate enhancement circuit is implemented to achieve a very high slew rate. The chip has been implemented in a 0.5μm CMOS process and the chip area of the operational amplifier circuit is 0.11 mm^2. The testing results indicate that in the 5-8 V input range, the maximum gm fluctuation is only 4.2%. The result exhibits a high slew rate of 111 V/μs and 102 V/μs for the rising and falling edges under a 20 pF capacitance load, and the low frequency gain is up to 109 dB with a phase margin of 70 ℃.  相似文献   

10.
An optical readout uncooled infrared (IR) imaging detector of bimaterial cantilever array using knife-edge filter operation (KEFO) is demonstrated. The angle change of each cantilever in a focal plane array (FPA) can be simultaneously detected with a resolution of 10-5 degree. A deformation magnifying substrate-free micro-cantilever unit with multi-fold interval metallized legs is specially designed and modeled. A FPA with 160×160 pixels is fabricated and thermal images with noise equivalent temperature difference (NETD) of 400 mK are obtained by this imaging detector.  相似文献   

11.
An integrated single-inductor dual-output (SIDO) switching DC-DC converter is presented. The outputs are specified with 1.2 V/400 mA and 1.8 V/200 mA. A decoupling small signal model is proposed to analyze the multi-loop system and to design the on-chip compensators. An average current control mode is introduced with lossless, continuous current detection. The converter has been fabricated in a 0.25μm 2P4M CMOS process. The power efficiency is 86% at a total output power of 840 mW while the output ripples are about 40 mV at an oscillator frequency of 600 kHz.  相似文献   

12.
Synthetic aperture radar (SAR) imaging system is generally realized by fixed-point with the purpose of reducing system implementation scale and enhancing real-time performance. Finite word length computing error of fixed-point SAR imaging system is studied. The characteristic of computing error in SAlt imaging system is analyzed. A finite word length computing error model of SAR imaging system is built, by means of which the empirical formula of system's output noise-to-signal ratio is derived. Based on the empirical formula, SAR imaging system processing word length is presented according to different processing granularities. The validity of this proposed finite word length computing error model of SAR imaging system is verified by system level fixed-point sivaulation.  相似文献   

13.
A chaos control strategy for chaotic current-mode boost converter is presented by using inductor current sampled feedback control technique.The quantitative analysis of control mechanism is performed by establishing a discrete alterative map of the controlled system.The stability criterion,feedback gain,and corresponding critical duty ratio are obtained from the eigenvalue of the map.The simulation results verify the t heoretical analysis results of the control strategy.  相似文献   

14.
To implement a fully-integrated on-chip CMOS power amplifier(PA) for RFID readers,the resonant frequency of each matching network is derived in detail.The highlight of the design is the adoption of a bonding wire as the output-stage inductor.Compared with the on-chip inductors in a CMOS process,the merit of the bondwire inductor is its high quality factor,leading to a higher output power and efficiency.The disadvantage of the bondwire inductor is that it is hard to control.A highly integrated class-E PA is implemented with 0.18-μm CMOS process.It can provide a maximum output power of 20 dBm and a 1 dB output power of 14.5 dBm.The maximum power-added efficiency(PAE) is 32.1%.Also,the spectral performance of the PA is analyzed for the specified RFID protocol.  相似文献   

15.
A 1-V third order one-bit continuous-time(CT) EA modulator is presented. Designed in the SMIC mixedsignal 0.13-μm CMOS process, the modulator utilizes active RC integrators to implement the loop filter. An efficient circuit design methodology for the CT ZA modulator is proposed and verified. Low power dissipation is achieved through the use of two-stage class A/AB amplifiers. The presented modulator achieves 81.4-dB SNDR and 85-dB dynamic range in a 20-kHz bandwidth with an over sampling ratio of 128. The total power consumption of the modulator is only 60 μW from a 1-V power supply and the prototype occupies an active area of 0.12 mm^2.  相似文献   

16.
A method of B-spline transform for signal feature extraction is developed. With the B-spline, the log-signal space is mapped into the vector space. An efficient algorithm based on Support Vector Machine (SVM) to automatically identify the water-flooded status of oil-saturated stratum is described. The experiments show that this algorithm can improve the performances for the identification and the generalization in the case of a limited set of samples.  相似文献   

17.
碱性铜抛光液在300mm平坦化系统中CMP工艺优化的研究   总被引:1,自引:1,他引:0  
CMP process optimization for bulk copper removal based on alkaline copper slurry was performed on a 300 mm Applied Materials Reflexion LK system. Under the DOE condition, we conclude that as the pressure increases, the removal rate increases and non-uniformity is improved. As the slurry flow rate increases, there is no significant improvement in the material removal rate, but it does slightly reduce the WIWNU and thus improve uniformity. The optimal variables are obtained at a reduced pressure of 1.5 psi and a slurry flow rate of 300 ml/min. Platen/carrier rotary speed is set at a constant value of 97/103 rpm. We obtain optimized CMP characteristics including a removal rate over 6452 A/min and non-uniformity below 4% on blanket wafer and the step height is reduced by nearly 8000 A/min in the center of the wafer on eight layers of copper patterned wafer, the surface roughness is reduced to 0.225 nm.  相似文献   

18.
Vehicle recognition system(VRS) plays a very important role in the field of intelligent transportation systems.A novel and intuitive method is proposed for vehicle location.The method we provide for vehicle location is based on human visual perception model technique.The perception color space HIS in this algorithm is adopted.Three color components of a color image and more potential edge patterns are integrated for solving the feature extraction problem.A fast and automatic threshold technique based on human visual perception model is also developed.The vertical edge projection and horizontal edge projection are adopted for locating left-right boundary of vehicle and top-bottom boundary of vehicle,respectively.Very promising experimental results are obtained using real-time vehicle image sequences,which have confirmed that this proposed location vehicle method is efficient and reliable,and its calculation speed meets the needs of the VRS.  相似文献   

19.
A semiconductor PEC etching method is applied to fabricate the n-type silicon deep micropore channel array. In this method, it is important to arrange the direction of the micropore array along the crystal orientation of the Si substrate. Otherwise, serious lateral erosion will happen. The etching process is also relative to the light intensity and HF concentration. 5% HF concentration and 10-15 cm distance between the light source and the silicon wafer are demonstrated to be the best in our experiments. The n-type silicon deep micropore channel array with aperture of 3/2m and aspect ratio of 40-60, whose inner walls are smooth, is finally obtained.  相似文献   

20.
A spectral numerical analysis method to analyze the Er-doped waveguide amplifiers(EDWA) in wavelength division multiplexing is presented. This model is based on finite difference beam propagation method modified by Douglas scheme, which can efficiently reduce the truncation error and time consumption. By superposing the Lorentzian function for the experimental curves, the spectral properties of EDWA can be investigated. Results show that the pump efficiency of EDWA pumped at 980 nm is higher than that at 1 480 nm. Meanwhile, by rationally increasing the pump length and the erbium concentration, larger signal gains can be acquired. Taking account of the up-conversion and cross-relaxation effects of cooperation, the spectrum analysis of highly doped EDWA is carried out over a wider frequency band.  相似文献   

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