一种1.25 Gbps CMOS以太网串并/并串转换电路

用0．35μm CMOS工艺实现了单芯片1．25Gbps千兆以太网串并／并串转换电路。该电路兼容ANSI的光纤信道物理层标准(FC-0)。与同类电路相比，其核心单元—并串转换电路和串并转换电路—具有结构简单、面积小的优点[1，2]，其高速串行数据随机抖功只有同类电路的一半。另外，电路中还集成了锁相环环路滤波电容。     

1.25 Gbps并串转换CMOS集成电路

分析了由超高速易重用单元构造的树型和串行组合结构 ,实现了在输入半速率时钟条件下 1 0路到1路吉比特率并串转换。通过理论推导着重讨论了器件延时和时钟畸变对并串转换的影响 ,指出了解决途径。芯片基于 0 .3 5μm CMOS工艺 ,采用全定制设计 ,芯片面积为 2 4.1 9mm2 。串行数据输出的最高工作速率达到 1 .62 Gbps,可满足不同吉比特率通信系统的要求。在 1 .2 5 Gbps标准速率 ,工作电压 3 .3 V,负载为 5 0 Ω的条件下 ,功耗为 1 74.84m W,输出电压峰 -峰值可达到 2 .42 V,占空比为 49% ,抖动为 3 5 ps rms。测试结果和模拟结果一致 ,表明所设计的电路结构在性能、速度、功耗和面积优化方面的先进性。文中设计的芯片具有广泛应用和产业化前景。     

一种全CMOS工艺吉比特以太网串并-并串转换电路

本文介绍了一种单片集成的吉比特以太网串并－并串转换电路。在芯片中，模拟锁相环产生1．25GHz高速时钟（当芯片用于光纤网络，时钟速率就为1．06GHz)，同时一个10到1多路选择器完成并行数据到串行的转换。在接收端，差分输入信号依次经过均衡电路、双端－单端转换电路转换成数字信号。同时，数据和时钟提取电路提取出时钟，并将数据重新同步。最后，串并转换电路完成串行－并行转换和字节同步。实验芯片采用0．35μmSPTM CMOS工艺，芯片面积为1．92mm^2，在最高输入输出数据波特率条件下的功耗为900mW。     

4Gbps低功耗并串转换CMOS集成电路

为满足传输数据的高速低功耗的要求,文章设计了一种半速率时钟驱动的二级多路选择开关式的10：1并串转换器。第一级为两个5：1的并行串化器,共用一个多相发生器。多相发生器由五个动态D触发器构成。第二级为一个2：1的并行串化器。采用半速率时钟、多路选择开关结构降低了大部分电路的工作频率,降低了工艺要求,也降低了功耗。通过调整时钟与数据间的相位关系,提高相位裕度,降低了数据抖动。采用1．8V 0．18μm CMOS工艺进行设计。用Hspice仿真器在各种PVT情况下做了仿真,结果表明该转换器在输出4Gbps数据时平均功耗为395μW,抖动18s^-1．     

一种采用半速结构的CMOS串行数据收发器的设计

设计了一种单片集成的CMOS串行数据收发器．该收发器用于线上速率为1.25Gb/s的千兆以太网中,全集成了发送和接收的功能,主要由时钟发生器、时钟数据恢复电路、并串／串并转换电路、线驱动器和均衡器组成．为了降低系统设计难度和电路功耗,收发器采用了半速率时钟结构．电路采用1.8V 0.18μm 1P6M CMOS数字工艺,芯片面积为2.0mm×1.9mm．经Cadence Spectre仿真验证以及流片测试,电路工作正常,功能良好．     

一种采用半速结构的CMOS串行数据收发器的设计

设计了一种单片集成的CMOS串行数据收发器.该收发器用于线上速率为1.25Gb/s的千兆以太网中,全集成了发送和接收的功能,主要由时钟发生器、时钟数据恢复电路、并串/串并转换电路、线驱动器和均衡器组成.为了降低系统设计难度和电路功耗,收发器采用了半速率时钟结构.电路采用1.8V 0.18μm 1P6M CMOS数字工艺,芯片面积为2.0mm×1.9mm.经Cadence Spectre仿真验证以及流片测试,电路工作正常,功能良好.     

一种高速并串转换控制电路设计

串行接口常用于高速数据传输,实现多路低速并行数据合成一路高速串行数据.设计了一种高速并串转换控制电路,实现在低频时钟控制下,通过内部锁相环(PLL)实现时钟倍频和数据选通信号,最终形成高速串行数据流,实现每5路全并行数据可按照顺序打包并转换为1路高速串行编码,最后通过一个低电压差分信号(LVDS)接口电路输出.该芯片通过0.18 μmCMOS工艺流片并测试验证,测试结果表明在120 MHz外部时钟频率下,该并串转换控制芯片能够实现输出速度600 Mbit/s的高速串行数据,输出抖动特性约为80 ps,整体功耗约为23 mW.     

接收器中并行数据与字节时钟同步的电路设计

在串并转换接收器中,并行数据在字节时钟的作用下并行输出.如何保证同一时刻输出的并行数据属于同一个字节,即并行数据与字节时钟的同步,是串并转换接受器中的一个关键问题.根据串并转换电路可以使用移位寄存结构,字节时钟可以在串行时钟的基础上使用计数器得到,而计数器又模可变的特点,设计了一种在数据的串并转换中进行并行数据与字节时钟同步的电路,经过理论分析与软件仿真,证明电路性能良好可行.     

基于65nm CMOS工艺的高速串并转换电路设计

本文介绍了一种适用于高速差分数据接收的CMOS串并转换电路,该电路主要由时钟电路、1：2数据分割电路和1：5分接器组成。采用65nm工艺,仿真结果表明,在数据传输速度为5Gb/s时功耗为12mW。     

树型结构串并转换电路的设计

采用DEMUX(多路分配器)分级解串、递减降速的树型结构,使电路获得较高转换速度,其优点是在时钟的上升和下降沿采样,充分利用了时钟周期。基于CMOS互补逻辑的电路结构降低了功耗,全定制的设计方法优化了电路性能和版图面积,提高了设计可靠性。本设计采用了华润上华0.6μm CMOS工艺。     

1.25～3.125 Gb/s连续数据速率CDR设计

设计了一款工作速率为1.25～3.125 Gb/s的连续可调时钟数据恢复(CDR)电路,可以满足多种通信标准的设计需求.CDR采用相位插值型双环路结构,使系统可以根据应用需求对抖动抑制和相位跟踪能力独立进行优化.针对低功耗和低噪声的需求,提出一种新型半速率采样判决电路,利用电流共享和节点电容充放电技术,数据速率为3.125 Gb/s时,仅需要消耗50 μA电流.芯片采用0.13 μm工艺流片验证,面积0.42 m㎡,功耗98 mw,测试结果表明,时钟数据恢复电路接收PRBS7序列时,误码率小于10-12.     

A 750 MHz semi-digital clock and data recovery circuit with 10~(-12) BER

A semi-digital clock and data recovery（CDR） is presented.In order to lower CDR trace jitter and decrease loop latency,an average-based phase detection algorithm is adopted and realized with a novel circuit. Implemented in a 0.13μm standard 1P8M CMOS process,our CDR is integrated into a high speed serial and de-serial（SERDES） chip.Measurement results of the chip show that the CDR can trace the phase of the input data well and the RMS jitter of the recovery clock in the observation pin is 122 ps at 75 MHz clock frequency,while the bit error rate of the recovery data is less than 10×10^-12.     

A CMOS 5.4/3.24‐Gbps Dual‐Rate CDR with Enhanced Quarter‐Rate Linear Phase Detector

This paper presents a clock and data recovery circuit that supports dual data rates of 5.4 Gbps and 3.24 Gbps for DisplayPort v1.2 sink device. A quarter‐rate linear phase detector (PD) is used in order to mitigate high speed circuit design effort. The proposed linear PD results in better jitter performance by increasing up and down pulse widths of the PD and removes dead‐zone problem of charge pump circuit. A voltage‐controlled oscillator is designed with a ‘Mode’ switching control for frequency selection. The measured RMS jitter of recovered clock signal is 2.92 ps, and the peak‐to‐peak jitter is 24.89 ps under 231–1 bit‐long pseudo‐random bit sequence at the bitrate of 5.4 Gbps. The chip area is 1.0 mm×1.3 mm, and the power consumption is 117 mW from a 1.8 V supply using 0.18 μm CMOS process.     

A 40 Gb/s Clock and Data Recovery Module with Improved Phase‐Locked Loop Circuits

A 40 Gb/s clock and data recovery (CDR) module for a fiber‐optic receiver with improved phase‐locked loop (PLL) circuits has been successfully implemented. The PLL of the CDR module employs an improved D‐type flip‐flop frequency acquisition circuit, which helps to stabilize the CDR performance, to obtain faster frequency acquisition, and to reduce the time of recovering the lock state in the event of losing the lock state. The measured RMS jitter of the clock signal recovered from 40 Gb/s pseudo‐random binary sequence (2³¹‐1) data by the improved PLL clock recovery module is 210 fs. The CDR module also integrates a 40 Gb/s D‐FF decision circuit, demonstrating that it can produce clean retimed data using the recovered clock.     

一种环路带宽自适应调整的时钟数据恢复电路

针对SONTE OC-192、PCIE3.0、USB3.2等协议在串行时钟数据恢复时对抖动容限、环路稳定时间的要求,提出了一种环路带宽自适应调整、半速率相位插值的时钟数据恢复电路(CDR)。设计了自适应控制电路,能适时动态调整环路带宽,实现串行信号时钟恢复过程中环路的快速稳定,提高了时钟数据恢复电路抖动容限。增加了补偿型相位插值控制器,进一步降低了数据接收误码率。该CDR电路基于55 nm CMOS工艺设计,数据输入范围为8～11.5 Gbit/s。采用随机码PRBS31对CDR电路的仿真测试结果表明,稳定时间小于400 ns,输入抖动容限大于0.55UI@10 MHz,功耗小于23 mW。     

一种全速率线性25Gb/s时钟数据恢复电路

面向高速光通信系统的应用,提出了一种全速率线性25Gb/s时钟数据恢复电路(Clock and Data Recovery Circuit,CDRC)。CDRC采用了混频器型线性鉴相器和自动锁频技术来实现全速率时钟提取和数据恢复。在设计中没有使用外部参考时钟。基于45nm CMOS工艺,该CDR电路从版图后仿真结果得到:恢复25Gb/s数据眼图的差分电压峰峰值V_pp和抖动峰峰值分别为1.3V和2.93ps;输出25GHz时钟的差分电压峰峰值V_pp和抖动峰峰值分别为1V和2.51ps,相位噪声为-93.6dBc/Hz@1MHz。该芯片面积为1.18×1.07mm²,在1V的电源电压下功耗为51.36mW。     

A 1.7 Gbps DLL‐Based Clock Data Recovery for a Serial Display Interface in 0.35‐μm CMOS

This paper presents a delay‐locked‐loop–based clock and data recovery (CDR) circuit design with a nB(n+2)B data formatting scheme for a high‐speed serial display interface. The nB(n+2)B data is formatted by inserting a ‘01’ clock information pattern in every piece of N‐bit data. The proposed CDR recovers clock and data in 1:10 demultiplexed form without an external reference clock. To validate the feasibility of the scheme, a 1.7‐Gbps CDR based on the proposed scheme is designed, simulated, and fabricated. Input data patterns were formatted as 10B12B for a high‐performance display interface. The proposed CDR consumes approximately 8 mA under a 3.3‐V power supply using a 0.35‐μm CMOS process and the measured peak‐to‐peak jitter of the recovered clock is 44 ps.     

A 2 Gbps to 12 Gbps Wide-Range CDR with Automatic Frequency Band Selector

The need for wide-band clock and data recovery(CDR) circuits is discussed.A 2 Gbps to 12 Gbps continuous-rate CDR circuit employing a multi-mode voltage-control oscillator(VCO),a frequency detector,and a phase detector(FD&PD) is described.A new automatic frequency band selection(FBS) without external reference clock is proposed to select the appropriate mode and also solve the instability problem when the circuit is powering on.The multi-mode VCO and FD/PD circuits which can operate at full-rate and half-rate modes facilitate CDR with six operation modes.The proposed CDR structure has been modeled with MATLAB and the simulated results validate its feasibility.     

2.5Gb/s 0.18μm CMOS时钟数据恢复电路

采用TSMC公司标准的0.18μm CMOS工艺,设计并实现了一个全集成的2.5Gb/s时钟数据恢复电路.时钟恢复由一个锁相环实现.通过使用一个动态的鉴频鉴相器,优化了相位噪声性能.恢复出2.5GHz时钟信号的均方抖动为2.4ps,单边带相位噪声在10kHz频偏处为-111dBc/Hz.恢复出2.5Gb/s数据的均方抖动为3.3ps.芯片的功耗仅为120mW.     

A low power DLL based clock and data recovery circuit with wide range anti-harmonic lock

This paper presents a wide frequency range CDR circuit for second generation AiPi+ intra-panel interface. The speed of the proposed clock and data recovery is increased to 1.25 Gbps compared with conventional AiPi+. The DLL-based CDR architecture is adopted to generate multi-phase clocks. We propose a simple scheme for a frequency detector (FD) to overcome the limited frequency range and false lock problem of a conventional delay-locked loop (DLL) to reduce the complexity. In addition, a duty cycle corrector that limits the maximum pulse width is used to avoid the problem of missing clock edges due to the mismatches between rising and falling time of delay cells in the VCDL. Also, the proposed simple DLL architecture comprised of frequency and phase detectors has better process-portability. The proposed CDR is implemented in 0.18 μm technology and the active die area is 660 × 250 μm. The implemented DLL covers a frequency range from 62 to 128 MHz, which is limited only by the characteristics of the delay cell. The peak-to-peak jitter is less than 13 ps when the input frequency is 128 MHz, and the power consumption of the CDR except the input buffer, equalizer, and de-serializer is 5.94 mW from the supply voltage of 1.8 V.