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A fast adaptive frequency calibration (AFC) technique with self-calibration for fast-locking phase-locked loops is presented with frequency-selecting switches. The proposed AFC directly calculates the proper switch states of the voltage-controlled oscillator (VCO). It requires only six clock cycles of the reference oscillator regardless of the number of VCO switches to reach the final switch state in the ideal case. The proposed method counts the number of VCO cycles per reference clock period for the minimum VCO frequency (MIN) and the maximum VCO frequency (MAX) during the first four-clock periods. For the following two-clock periods, the proper states of the VCO switches are set to the calculated value from MIN, MAX and the desired division ratio for a target frequency (EST). A frequency synthesiser with the proposed AFC was implemented on a 0.18?µm CMOS process. The AFC time decreased from 40 to 0.4?µs employing the proposed scheme such that the total lock time is 40?µs with the loop bandwidth of 40?kHz. 相似文献
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This paper presents a low phase-noise fractional-N frequency synthesizer which provides an inphase/quadrature-phase(I/Q) signal over a frequency range of 220–1100 MHz for wireless networks of industrial automation(WIA) applications. Two techniques are proposed to achieve the wide range. First, a 1.4–2.2 GHz ultralow gain voltage-controlled oscillator(VCO) is adopted by using 128 tuning curves. Second, a selectable I/Q divider is employed to divide the VCO frequency by 2 or 3 or 4 or 6. Besides, a phase-switching prescaler is proposed to lower PLL phase noise, a self-calibrated charge pump is used to suppress spur, and a detect-boosting phase frequency detector is adopted to shorten settling time. With a 200 k Hz loop bandwidth, lowest measured phase noise is 106 d Bc/Hz at a 10 k Hz offset and 131 d Bc/Hz at a 1 MHz offset. Fabricated in the TSMC 0.18 m CMOS process, the synthesizer occupies a chip area of 1.2 mm2, consumes only 15 m W from the 1.8 V power supply,and settles within 13.2 s. The synthesizer is optimized for the WIA applications, but can also be used for other short-range wireless communications, such as 433, 868, 916 MHz ISM band applications. 相似文献
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A dual-loop phase-locked loop(PLL)for wideband operation is proposed.The dual-loop architecture combines a coarse-tuning loop with a fine-tuning one,enabling a wide tuning range and low voltage-controlled oscillator(VCO)gain without poisoning phase noise and reference spur suppression performance.An analysis of the phase noise and reference spur of the dual-loop PLL is emphasized.A novel multiple-pass ring VCO is designed for the dual-loop application.It utilizes both voltage-control and current-control simultaneously in the delay cell. The PLL is fabricated in Jazz 0.18-μm RF CMOS technology.The measured tuning range is from 4.2 to 5.9 GHz.It achieves a low phase noise of–99 dBc/Hz@1 MHz offset from a 5.5 GHz carrier. 相似文献
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A dual-loop phase-locked loop (PLL) for wideband operation is proposed. The dual-loop architecture combines a coarse-tuning loop with a fine-tuning one, enabling a wide tuning range and low voltage-controlled oscillator (VCO) gain without poisoning phase noise and reference spur suppression performance. An analysis of the phase noise and reference spur of the dual-loop PLL is emphasized. A novel multiple-pass ring VCO is designed for the dual-loop application. It utilizes both voltage-control and current-control simultaneously in the delay cell. The PLL is fabricated in Jazz 0.18-μm RF CMOS technology. The measured tuning range is from 4.2 to 5.9 GHz. It achieves a low phase noise of-99 dBc/Hz @ 1 MHz offset from a 5.5 GHz carrier. 相似文献
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用0.25μm标准CMOS工艺实现了单次变频数字有线电视调谐器中的频率合成器.它集成了频率合成器中除LC调谐网络和有源滤波器外的其他模块.采用I2C控制三个波段的VCO相互切换,片内自动幅度控制电路和用于提升调谐电压的片外三阶有源滤波器,实现VCO的宽范围稳定输出.改进逻辑结构的双模16/17预分频器提高了电路工作速度.基于环路的行为级模型,对环路参数设计及环路性能评估进行了深入的讨论.流片测试结果表明,该频率合成器的锁定范围为75~830MHz,全波段内在偏离中心频率10kHz处的相位噪声可以达到-90.46dBc/Hz,100kHz处的相位噪声为-115dBc/Hz,参考频率附近杂散小于-90dBc. 相似文献
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宽带低相位噪声锁相环型频率合成器的CMOS实现 总被引:1,自引:3,他引:1
用0.25μm标准CMOS工艺实现了单次变频数字有线电视调谐器中的频率合成器.它集成了频率合成器中除LC调谐网络和有源滤波器外的其他模块.采用I2C控制三个波段的VCO相互切换,片内自动幅度控制电路和用于提升调谐电压的片外三阶有源滤波器,实现VCO的宽范围稳定输出.改进逻辑结构的双模16/17预分频器提高了电路工作速度.基于环路的行为级模型,对环路参数设计及环路性能评估进行了深入的讨论.流片测试结果表明,该频率合成器的锁定范围为75~830MHz,全波段内在偏离中心频率10kHz处的相位噪声可以达到-90.46dBc/Hz,100kHz处的相位噪声为-115dBc/Hz,参考频率附近杂散小于-90dBc. 相似文献
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本文实现了一种集成新型相位切换预分频器和高品质因素压控振荡器的锁相环频率综合器。该频率综合器在考虑噪声性能的基础上进行系统参数设计。预分频器采用了一种不易受工艺偏差影响的相位切换方式。对压控振荡器的电感开关电容和压控电容的品质因素进行了优化。与其他文献相比,该频率综合器使用相近的功耗取得更好的噪声性能。本文提出的频率综合器采用SMIC0.13微米工艺流片,芯片面积为11502500 μm2。当锁定在5 GHz时,其功耗在1.2V电源电压供电时为15mA。此时,1MHz频偏处相位噪声为-122.45dBc/Hz。 相似文献
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Chester Sungchung Park 《International Journal of Electronics》2018,105(7):1200-1216
A low-power mixed-signal phase-locked loop (PLL) is modelled and designed for the DigRF interface between the RF chip and the modem chip. An assisted-GPS or A-GPS multi-standard system includes the DigRF interface and uses the split automatic frequency control (AFC) technique. The PLL circuitry uses the direct AFC technique and is based on the fractional-N architecture using a digital delta-sigma modulator along with a digital counter, fulfilling simple ultra-high-resolution AFC with robust digital circuitry and its timing. Relative to the output frequency, the measured AFC resolution or accuracy is <5 parts per billion (ppb) or on the order of a Hertz. The cycle-to-cycle rms jitter is <6 ps and the typical settling time is <30 μs. A spur reduction technique is adopted and implemented as well, demonstrating spur reduction without employing dithering. The proposed PLL includes a low-leakage phase-frequency detector, a low-drop-out regulator, power-on-reset circuitry and precharge circuitry. The PLL is implemented in a 90-nm CMOS process technology with 1.2 V single supply. The overall PLL draws about 1.1 mA from the supply. 相似文献
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本文提出了一个适用于Δ-Σ模数转换器的基于锁相环结构的频率综合器,该频率综合器使用65纳米CMOS工艺实现,频率范围为35-130和300-360兆赫兹。文中提出的频率综合器能够工作在低相位噪声模式和低功耗模式,从而满足系统要求。为了实现这两个模式的切换,片上集成了一个连接4分频器的高频LC压控振荡器和一个连接2分频器的环形压控振荡器。测试结果表明,在1.2伏电源电压下,该频率综合器在低相位噪声模式下消耗1.74毫瓦功耗,1兆频偏处的相位噪声为-132dBc/Hz,标准差周期抖动为1.12皮秒;在低功耗模式下消耗0.92毫瓦功耗,1兆频偏处的相位噪声为-112dBc/Hz,标准差周期抖动为7.23皮秒。 相似文献
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In this paper, we present a new low power down-conversion mixer design with single RF and LO input topology which consumes 48 μW power. Detailed analysis of the mixer has been provided. Using the presented mixer as a phase-detector, a low power phase-locked loop (PLL) has been designed and fabricated. A PLL based receiver architecture has been developed and analyzed. The circuit has been fabricated through 0.13 μm CMOS technology. Dissipating 0.26 mW from a 1.2 V supply, the fabricated PLL can track signals between 1.62 and 2.49 GHz. For receiver applications, the energy per bit of the receiver is only 0.26 nJ making it attractive for low power applications including wireless sensor networks. 相似文献
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In millimeter wave systems, performance degradation mainly occurs due to high phase noise of voltage-controlled oscillators (VCOs). This paper proposes a low power, low phase noise ring-VCO developed for ultra-wide band applications identified for possible 5G usage. For this purpose, a novel differential symmetrical load delay cell based 3-stage ring oscillator has been introduced to design the ring-VCO. The 28 nm CMOS Fully Depleted Silicon On Insulator (FDSOI) technology is adopted for designing this VCO circuit with 1 V power supply while a new voltage control through the transistor body bias is implemented. The simulated results show that the proposed oscillator works in the tuning range of 29–49 GHz and dissipates 3.75 mW of power. It exhibits a phase noise of −129.2 dBc/Hz at 1 MHz offset from 49 GHz oscillation frequency, and a remarkable Figure of Merit (FoM) of −217.26 dBc/Hz. With similar power supply, the phase noise rises to −93.16 dBc/Hz for a second oscillator involving more of active components exactly 9 delay cells. Further, the impact of the operation temperature variation on the VCO performance is investigated. Results show a drift in the oscillation frequency for a temperature step from 27 °C to 40 °C and a degradation of 3dBc in the phase noise performance. 相似文献
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在锁相环设计中,双模前置分频器(dual—modulus prescaler)是一个速度瓶颈,而D触发器是限制其速度的主要因素。我们对传统的Yuan-Svensson真正单相时钟(TSPC)D触发器(DFF)做了改进,给出了动态有比D触发器的结构,该触发器结构简单,工作频率高,功耗低。并基于此设计了一个可变分频比双模前置分频器,可适用于多种无线通信标准。采用0.35μm CMOS工艺参数进行仿真,结果表明,在3.3V电源电压下其工作频率可达4.1GHz。 相似文献
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A new method is proposed in this article to accomplish the fine tune unit of the digitally controlled oscillator of an all-digital phase-locked loop (ADPLL). Instead of using adjustable currents, we utilise the difference of the equivalent capacitance obtained from the drain of MOS transistors between on and off states as the fine tune delay parameter. Based on post-layout simulation results, the time resolution of the fine tune delay element can achieve results as good as 1.7126 ps. The operating frequency of this presented ADPLL ranges from 308 to 587 MHz. As compared to prior arts, the power consumption per MHz is reduced over 15% and the jitter is as low as 5 ps, which is a significant improvement. 相似文献