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《Electronics letters》2009,45(3):150-151
A simple method for reducing the cycle-to-cycle jitter of clock signals is described. The method uses Muller-C elements to merge redundant clock signals. If the two clock signals have nearly the same average phase and independently-distributed phase noise, then the jitter at the Muller-C element?s output is less than that of the input signals. This method can be used to reduce jitter in sampling clocks for analogueto- digital conversion, and in clock distribution networks for VLSI systems. 相似文献
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In the letter we present a new clock recovery circuit with self-correction of the position of the retiming clock, which shows the reduction of the output jitter by deleting the phase difference of ? radians in the output of the phase detector existing in Hogge's scheme. 相似文献
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This paper presents a half-rate clock and data recovery circuit (CDR)that combines the fast acquisition of a phase selection (PS) delay-locked loop (DLL) with the low jitter of a phase-locked loop (PLL). The PLL acquisition time improves considerably with use of a phase frequency magnitude detector(PFMD) that feeds back an estimate of the magnitude of the frequency difference in addition to the sign. Measurements in 0.5/spl mu/m CMOS technology show operation up to 700 Mb/s, a 7% acquisition range, an initial acquisition time of 8 bit times with jitter of 30% bit time, and jitter of 16 ps after the PLL acquires lock. With a phase frequency detector (PFD), the PLL locks in about 700 ns from an initial frequency difference of 7%. Measurements using a PFMD show the 700 ns PLL acquisition time is reduced on average by about a factor of 5 to 140 ns from an initial 7% frequency difference. The power dissipation is 300mW. 相似文献
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A fully integrated low-jitter,precise frequency CMOS phase-locked loop(PLL) clock for the phase change memory(PCM) drive circuit is presented.The design consists of a dynamic dual-reset phase frequency detector(PFD) with high frequency acquisition,a novel low jitter charge pump,a CMOS ring oscillator based voltage-controlled oscillator(VCO),a 2nd order passive loop filter,and a digital frequency divider.The design is fabricated in 0.35μm CMOS technology and consumes 20 mW from a supply voltage of 5 V.In terms of the PCM’s program operation requirement,the output frequency range is from 1 to 140 MHz.For the 140 MHz output frequency,the circuit features a cycle-to-cycle jitter of 28 ps RMS and 250 ps peak-to-peak. 相似文献
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针对参考时钟源高电平脉冲宽度窄(小于2 ns)和本底噪声大的问题,通过使用一种时钟低抖动整形技术方案,使参考时钟经过锁相整形后高电平脉冲宽度大于3 ns、锁相相位时间抖动均方根(RMS)值小于5 ps。目前该方案已成功用于星光III激光装置的联机实验,情况良好,对其他类似需要精密时钟的装置具有极大的借鉴意义。 相似文献
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When multimedia streams arrive at the receiver, their temporal relationships may be distorted due to jitter. Assuming the media stream is packetized, the jitter is then the packet's arrival time deviation from its expected arrival time. There are various ways to reduce jitter, which include synchronization at the application layer, or synchronization at the asynchronous transfer mode (ATM) adaptation layer (AAL). The new source rate recovery scheme called jitter time-stamp (JTS) provides synchronization at the ATM adaptation layer 2 (AAL2) which is used to carry variable bit-rate traffic such as compressed voice and video. JTS is implemented, and experiments have shown that it is able to recover the source rate 相似文献
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Brad Brannon 《电子设计技术》2005,12(3):66-66,68,70,72,74,76
随着直接中频采样的更高分辨力数据转换器的上市,系统设计师必须对低抖动时钟电路做出有助于性能与成本折衷的抉择。制造商用来规定时钟抖动的很多传统方法并不适用于数据转换器,或者说,充其量也只能反映问题的一部分。如果对时钟电路的规范和设计没有恰当的了解,你就不能实现这些数据转换器的最佳性能。 相似文献
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We derive an analytical expression for the variance of the timing jitter of a soliton transmission system using sliding-frequency guiding filters, taking into account the third-order filter term. An improved analytical result for the upper limit of the sliding rate for stable soliton propagation is also obtained. We show that the variance of timing jitter is significantly increased by the sliding action. As a consequence of the third-order filter contribution, the timing jitter is lower in a system with down-sliding compared with the up-sliding regime at the same sliding rate 相似文献
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The authors propose to use dispersion management to reduce collision-induced timing jitter in soliton WDM transmission. The performance of dispersion-managed fibres is compared numerically to dispersion-decreasing and uniform dispersion fibres with up to eight channels, and it is shown that dispersion management can provide the best performance 相似文献
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Dejan Radjen Pietro Andreani Martin Anderson Lars Sundström 《Analog Integrated Circuits and Signal Processing》2013,74(1):21-31
The performance of continuous time delta-sigma modulators is limited by their large sensitivity to feedback pulse-width variations caused by clock jitter in their feedback DACs. To mitigate that effect, a dual switched-capacitor-resistor feedback DAC technique is proposed. The architecture has the additional benefit of reducing the typically high switched-capacitor-resistor DAC output peak currents, resulting in reduced slew-rate requirements for the loop-filter integrators. The feedback technique has been implemented with a third order, 3-bit delta-sigma modulator for a low power radio receiver, in a 65 nm CMOS process, where it occupies an area of 0.17 mm2. It achieves an SNDR of 70 dB over a 125 kHz bandwidth with an oversampling ratio of 16. The power consumption is 380 μW from a 900 mV supply. 相似文献
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The effect of optical phase conjugation on Gordon-Haus jitter in long-distance soliton communication systems is considered. In-line optical phase conjugation at an optimal point two-thirds of the way down the system reduces the rms jitter by a factor of three. A post-transmission-line compensation scheme based on optical phase conjugation and soliton-supported dispersion compensation reduces the rms jitter by a factor of two 相似文献
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The letter considers the timing content of a random data sequence and presents a line coding technique to achieve reliable, low-jitter timing recovery. 相似文献
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This paper describes a low-voltage low-jitter clock synthesizer and a temperature-compensated tunable oscillator. Both of these circuits employ a self-correcting delay-locked loop (DLL) which solves the problem of false locking associated with conventional DLLs. This DLL does not require the delay control voltage to be set on power-up; it can recover from missing reference clock pulses and, because the delay range is not restricted, it can accommodate a variable reference clock frequency. The DLL provides multiple clock phases that are combined to produce the desired output frequency for the synthesizer, and provides temperature-compensated biasing for the tunable oscillator. With a 2-V supply the measured rms jitter for the 1-GHz synthesizer output was 3.2 ps. With a 3.3-V supply, rms jitter of 3.1 ps was measured for a 1.6-GHz output. The tunable oscillator has a 1.8% frequency variation over an ambient temperature range from 0°C to 85°C. The circuits were fabricated on a generic 0.5-μm digital CMOS process 相似文献
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Hsiang-Hui Chang Rong-Jyi Yang Shen-Iuan Liu 《IEEE transactions on circuits and systems. I, Regular papers》2004,51(12):2356-2364
A fully integrated clock and data recovery circuit (CDR) using a multiplying shifted-averaging delay locked loop and a rate-detection circuit is presented. It can achieve wide range and low jitter operation. A duty-cycle-insensitive phase detector is also proposed to mitigate the dependency on clock duty cycle variations. The experimental prototype has been fabricated in a 0.25-/spl mu/m 1P5M CMOS technology and occupies an active area of 2.89 mm/sup 2/. The measured CDR could operate from 125 Mb/s to 2.0 Gb/s with a bit error rate better than 10/sup -12/ from a 2.5-V supply. Over the entire operating frequency range, the maximum rms jitter of the recovered clock is less than 4 ps. 相似文献