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针对开关稳压器中负载电流检测难以同时做到准确、同步和结构简单这一难题,结合自己多年工作经验,提出了一种新颖的开关稳压器负载电流检测的新方法。其基本原理是利用断续模式(DCM)下负载电流与同步管栅极驱动信号N_DRV的同步关系,通过检测该栅极信号来检测开关稳压器的输出负载电流。这种方法不仅使负载电流检测同步和准确,且同时克服检测电感平均电流带来的电路结构复杂及实现上的困难。该电路经过HSpice仿真验证,其仅消耗5μA的静态电流,工作状态良好。 相似文献
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一种基于开关电容技术的锁定放大器设计 总被引:1,自引:0,他引:1
锁定放大是微弱信号检测的重要手段.基于相关检测理论,利用开关电容的开关实现锁定放大器中乘法器的功能,提出开关电容和积分器相结合以实现相关检测的方法,并设计出一种锁定放大器.该锁定放大器将微弱信号转化为与之相关的方波,通过后续电路得到正比于被测信号的直流电平,为后续采集处理提供方便.测量数据表明锁定放大器前级可将10-6A的电流转换为10-1V的电压,后级通过带通滤波器级联可将信号放大1×105倍.该方法在降低噪声的同时,可对微弱信号进行放大,线性度较高、稳定性较好. 相似文献
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就电流开关驱动器对高速电流型DAC动态性能的影响因素进行了分析,给出了设计应对措施,并设计了一种结构简单使用了同步锁存技术、低驱动信号摆幅技术和低信号交叉点技术的电流开关驱动器电路.基于SMIC 0.18μm CMOS工艺模型,采用Hspice仿真工具,对电流开关驱动器进行仿真分析,结果表明所设计驱动器电路功能正确.测试结果表明,应用该电流开关驱动器的一款嵌入式14位400MSPS DAC电路在输出80 MHz正弦信号时,达到76.47 dB的无杂散动态范围,所设计电流开关驱动器能保证高速电流型DAC的良好动态性能. 相似文献
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一种BUCK型开关稳压器负载电流检测电路 总被引:3,自引:0,他引:3
针对Buck型开关稳压器的断续工作模式(DCM),基于CSMC0.5μm CMOS工艺设计实现了一种新颖的负载电流检测电路。同传统的电感电流采样方式不同,该结构直接应用与负载电流变化几乎同步的同步管栅极驱动信号作为"电流采样"信号,实现了负载平均电流的检测。经投片验证,提出的电流检测电路工作良好,且面积仅占芯片的1.5%,同传统采样方式相比,面积减小了21%,静态时的耗电仅为原来的40%。 相似文献
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锁相环同步检波技术及在视频检波中的应用 总被引:1,自引:0,他引:1
早期电视机的视频检波均采用大信号包络检波电路,后来在集成化的电视机中,视频检波又都采用同步检波方式。虽然这种同步检波比大信号包络检波电路有明显的改进,但还是存在一些不足,不能做到真正的同步。针对上述不足,介绍一种先进的视频检波方式——锁相环同步检波,他可以克服上述的缺点,做到真正的同步。该检波方式在现代大屏幕彩色电视机的视频检波中取得很好的效果,并得到广泛应用。 相似文献
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G.N. Lu P. Pittet G. Sou G. Carrillo A. El Mourabit 《Analog Integrated Circuits and Signal Processing》2003,37(1):57-66
A phase-switching approach suppresses the need to employ a precise multiplier for synchronous demodulation. An improved solution for implementing on-chip synchronous detection consists of using a switched-phase amplifier, which combines pre-amplification and phase-switching operations. This enables circuit simplification, voltage lowering, and power and surface savings. A detector-associated circuit realising pre-amplification and synchronous demodulation is proposed. It includes a transimpedance amplifier, a switched-phase amplifier and a low-pass filter. All these building blocks are designed to operate under a minimum supply of 2 V, using a double-poly, 0.8-m CMOS process. The designed circuit is to be integrated with a CMOS optical detector for portable applications. System-level simulations (including the detector model) are performed to validate the system operation, and to estimate performances. The sensitivity of the system in terms of minimum detectable optical signal (which is synchronously modulated) is evaluated to be 2.2 10–14 W/mm2 in normal measuring conditions. 相似文献
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《Solid-State Circuits, IEEE Journal of》1968,3(4):373-380
A fully balanced analog multiplier using differential transistor pairs is briefly described. Several circuit functions usually required in communication systems can be derived from the basic circuit. In particular, the different modes of operation leading to FM detection, suppressed carrier modulation, synchronous AM detection, and TV chroma demodulation are discussed. Experimental data obtained with a monolithic analog multiplier are also presented. 相似文献
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When a p.s.k. signal is synchronous, i.e. the transmitted signal is phase-locked to the data, it carries extra information which allows demodulation without ambiguity. A simple practical demodulator circuit is described, which, in long term use, has proved to be very successful. 相似文献
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开关键控调幅体制(OOK)信号为开关键控的调幅信号,利用在不同位置上的通断传递不同的信息,对脉冲位置的精确度将决定最终的解调误码率。根据遥测中频OOK信号的解调原理,介绍了OOK解调的理论架构和实现方法。通过理论分析、公式推导和matlab仿真等手段证明了方法的正确性,在此基础上完成VHDL程序设计,进行了仿真测试和实验验证,仿真结果和实验结果证明了该实现方法的可行性。 相似文献
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A digital detection technique based on the coordinate rotation digital computer (CORDIC) algorithm is proposed for a resonator fiber optic gyroscope (R-FOG). It makes the generation of modulation signal, synchronous demodulation and signal processing in R-FOG to be realized in a single field programmable gate array (FPGA). The frequency synthesis and synchronous detection techniques based on the CORDIC algorithm have been analyzed and designed firstly. The experimental results indicate that the precision of the detection circuit satisfies the requirements for the closed-loop feedback in R-FOG system. The frequency of the laser is locked to the resonance frequency of the fiber ring resonator stably and the open-loop gyro output signal is observed successfully. The dynamic range and the bias drift of the R-FOG are ±1.91 rad/s and 0.005 rad/s over 10 s, respectively. 相似文献