2.5-Gb/s low-jitter low-power monolithically integrated optical receiver

A high-scale integrated optical receiver including a preamplifier, a limiting amplifier, a clock and data recovery (CDR) block, and a 1:4 demultiplexer (DEMUX) has been realized in a 0.25???m CMOS technology. Using the loop parameter optimization method and the low-jitter circuit design technique, the rms and peak-to-peak jitter of the recovered 625-MHz clock are 9.4 and 46.3?ps, respectively, which meet the jitter specifications stipulated in ITU-T recommendation G.958. The recovered and frequency divided 625?MHz clock has a phase noise of ?83.8 dBc/Hz at 20?kHz offset in response to 2.5?Gb/s PRBS input data (2²³?C1), and the 2.5?Gb/s PRBS data has been demultiplexed into four 625?Mb/s data. The power dissipation is only 0.3?W under a single 3.3 V supply (excluding output buffers).     

A 2.5-Gb/s clock and data recovery IC with tunable jittercharacteristics for use in LANs and WANs

A 2.5-Gb/s monolithic clock and data recovery (CDR) IC using the phase-locked loop (PLL) technique is fabricated using Si bipolar technology. The output jitter characteristics of the CDR can be controlled by designing the loop-gain design and by using the switched-filter PLL technique. The CDR IC can be used in local-area networks (LANs) and in long-haul backbone networks or wide-area networks (WANs). Its power consumption is only 0.4 W. For LANs, the jitter generation of the CDR when the loop gain is optimized is 1.2 ps (0.003 UI). The jitter characteristics of the CDR optimized for WANs meet all three types of STM-I6 jitter specifications given in ITU-T Recommendation G.958. This is the first report on a CDR that can be used for both LAN's and WAN's. This paper also describes the design method of the jitter characteristics of the CDR for LANs and WANs     

PLL design technique by a loop-trajectory analysis taking decision-circuit phase margin into account for over-10-Gb/s clock and data recovery circuits

A design technique for an over-10-Gb/s clock and data recovery (CDR) IC provides good jitter tolerance and low jitter. To design the CDR using a PLL that includes a decision circuit with a certain phase margin affecting the pull-in performance, we derived a simple expression for the pull-in range of the PLL, which we call the "limited pull-in range," and used it for the pull-in performance evaluation. The method allows us to quickly and easily compare the pull-in performance of a conventional PLL with a full-rate clock and a PLL with a half-rate clock, and we verified that the half-rate PLL is advantageous because of its wider frequency range. For verification of the method, we fabricated a half-rate CDR with a 1:16 DEMUX IC using commercially available Si bipolar technology with f/sub T/=43 GHz. The half-rate clock technique with a linear phase detector, which is adopted to avoid using the binary phase detector often used for half-rate CDR ICs, achieves good jitter characteristics. The CDR IC operates reliably up to over 15 Gb/s and achieves jitter tolerance with wide margins that surpasses the ITU-T specifications. Furthermore, the measured jitter generation is less than 0.4 ps rms, which is much lower than the ITU-T specification. In addition, the CDR IC can extract a precise clock signal under harsh conditions, such as when the bit error rate of input data is around 2/spl times/10/sup -2/ due to a low-power optical input of -24 dBm.     

InP DHBT-Based Monolithically Integrated CDR/DEMUX IC Operating at 80 Gbit/s

In this paper, a monolithically integrated clock and data recovery (CDR) circuit with 1:2 demultiplexer (DEMUX), which is intended for use in 80 Gbit/s optical fiber links, is presented. The integrated circuit (IC) is manufactured using an in-house InP double heterostructure bipolar transistor (DHBT) technology, exhibiting cut-off frequency values of more than 220 GHz for both$f_T$and$f_max $. The CDR circuit in the topology of a phase-locked loop (PLL) is mainly composed of a half-rate linear phase detector including a 1:2 demultiplexer (DEMUX), a loop filter, and a voltage-controlled oscillator (VCO). Hence, the corresponding architecture of each of these components as well as the applied circuit design technique are extensively addressed. Concerning the performance achieved by the CDR/DEMUX IC, the recovered and demultiplexed 40 Gbit/s data from an 80 Gbit/s input signal feature clear eye opening with a signal swing as high as 600$hboxmV_ pp$. The extracted 40 GHz clock signal shows a phase noise as low as$- hbox98~dBc/hboxHz$at 100 kHz offset frequency. The corresponding rms jitter amounts to 0.37 ps while the peak-to-peak jitter is as low as 1.66 ps. At a single supply voltage of$-hbox4.8~V$, the power consumption of the full CDR/DEMUX IC amounts to 1.65 W. To the authors' best knowledge, this work demonstrates the first CDR circuit at the achieved data rate, regardless of all the competing semiconductor technologies.     

Low-jitter design method based on Wn-domain jitter analysis for 10 Gbit/s clock and data recovery ICs

A low-jitter design method based on vn-domain jitter analysis for the clock and data recovery (CDR) ICs using the linear phase-locked loop (PLL) is proposed. Using this method, the loop parameters of the PLL can be optimised, which makes it possible to design the CDR IC for various targets.     

2.5 Gbit/s clock and data recovery circuit IC using novelduplicated PLL technique

A 2.5 Gbit/s monolithic clock and data recovery integrated circuit (CDR IC) based on a novel duplicated phase-locked loop (PLL) technique has been fabricated using 0.5 μm Si bipolar technology. This CDR IC operates more stably in that it can tolerate greater variations in temperature and supply voltage while continuing to meet the specifications for jitter characteristics stipulated in the ITU-T recommendations     

SiGe clock and data recovery IC with linear-type PLL for 10-Gb/sSONET application

An integrated 10 Gb/s clock and data recovery (CDR) circuit is fabricated using SiGe technology, It consists of a linear-type phase-locked loop (PLL) based on a single-edge version of the Hogge phase detector, a LC-tank voltage-controlled oscillator (VCO) and a tri-state charge pump. A PLL equivalent model and design method to meet SONET jitter requirements are presented. The CDR was tested at 9.529 GB/s in full operation and up to 13.25 Gb/s in data recovery mode. Sensitivity is 14 mV_pp at a bit error rate (BER)=10^-9 . The measured recovered clock jitter is less than 1 ps RMS. The IC dissipates 1.5 W with a -5 V power supply     

Low-power 1:16 DEMUX and one-chip CDR with 1:4 DEMUX using InP-InGaAs heterojunction bipolar transistors

Using InP-InGaAs heterojunction bipolar transistor (HBT) technology, we have successfully designed and fabricated a low-power 1:16 demultiplexer (DEMUX) integrated circuit (IC) and one-chip clock and data recovery (CDR) with a 1:4 DEMUX IC for 10-Gb/s optical communications systems. The InP-InGaAs HBTs were fabricated by a nonself-aligned process for high uniformity of device characteristics and producibility. The 1:16 DEMUX IC and the one-chip CDR with the 1:4 DEMUX IC consist of approximately 1200 and 460 transistors, respectively. We have confirmed error-free operation at 10 Gb/s for all data outputs of both ICs. The 1:16 DEMUX IC and the one-chip CDR with the 1:4 DEMUX IC consume only 1 W and 950 mW, respectively. These results demonstrate the feasibility of InP-InGaAs HBTs for low power high-integration optical communication ICs.     

40 Gb/s Transimpedance-AGC Amplifier and CDR Circuit for Broadband Data Receivers in 90 nm CMOS

High-speed front-end amplifiers and CDR circuits play critical roles in broadband data receivers as the former needs to perform amplification at high data rate and the latter has to retime the data with the extracted low-jitter clock. In this paper, the design and experimental results of 40 Gb/s transimpedance-AGC amplifier and CDR circuit are described. The transimpedance amplifier incorporates reversed triple-resonance networks (RTRNs) and negative feedback in a common-gate configuration. A mathematical model is derived to facilitate the design and analysis of the RTRN, showing that the bandwidth is extended by a larger factor compared to using the shunt-series peaking technique, especially in cases when the parasitic capacitance is dominated by the next stage. Operating at 40 Gb/s, the amplifier provides an overall gain of 2 kOmega and a differential output swing of 520 mV_pp with for input spanning from to . The measured integrated input-referred noise is 3.3muA_rms. The half-rate CDR circuit employs a direction-determined rotary-wave quadrature VCO to solve the bidirectional-rotation problem in conventional rotary-wave oscillators. This guarantees the phase sequence while negligibly affecting the phase noise. With 40 Gb/s 2³¹ - 1 PRBS input, the recovered clock jitter is and 0.7ps_rms. The retimed data exhibits 13.3 ps_pp jitter with BER . Fabricated in 90 nm digital CMOS technology, the overall amplifier consumes 75 mW and the CDR circuit consumes 48 mW excluding the output buffers, all from a 1.2 V supply.     

A 40–44 Gb/s 3× Oversampling CMOS CDR/1:16 DEMUX

A CMOS CDR and 1:16 DEMUX fabricated in a low-cost 90 nm bulk CMOS process operates at 40-44 Gb/s and dissipates 910 mW. A quarter-rate hybrid phase-tracking/3times blind-oversampling architecture is used to improve jitter tolerance, reduce the need for high-power CML circuits, and enable frequency acquisition without a reference clock. Input data are sampled using a 24-phase distributed VCO, and a digital CDR recovers 16 bits and a 2.5 GHz clock from 48 demultiplexed samples spanning 16 UI. Conformance to the ITU-T G.8251 jitter tolerance mask (BER <10^-12 with a 2³¹-1 PRBS source) is demonstrated using both an on-chip and an external BERT.     

A 10-Gb/s CMU/CDR chip-set in SiGe BiCMOS commercial technology with multistandard capability

A 10-Gb/s CMU/CDR chip-set presenting multistandard compliance with SDH/SONET and 10-GbE specifications has been fabricated in a commercial SiGe BiCMOS technology. The clock multiplier unit (CMU) features dual reference clock frequency, and the phase tracking loop uses a charge pump with low common-mode current to minimize frequency ripple; the output jitter is below 80 mUIpp. The clock and data recovery (CDR) features a 20-mV-sensitivity limiting amplifier, a 2-DFF-based decision circuit to maximize clock phase margin (CPM) and a dual-loop phase-locked loop (PLL) architecture with external reference clock. A novel phase detector topology featuring a transition density factor compensation loop has been exploited to minimize jitter. Power consumption is 480 mW and 780 mW, respectively, for the two ICs, from 3.3-V and 2.5-V power supplies     

A 2.4 Gb/s receiver and a 1:16 demultiplexer in one chip using asuper self-aligned selectively grown SiGe base (SSSB) bipolar transistor

This paper reports a 2.4 Gb/s optical terminal IC that integrates high-speed analog and digital circuits for future optical networks using 60-GHz f_T self-aligned silicon-germanium (SiGe)-alloy base bipolar transistors. The selective epitaxial growth (SEG) SiGe base was formed by using cold-wall ultra-high vacuum (UHV)/CVD technology. Boron concentration reduction at the SiGe epitaxial layer/Si-substrate interface by using a new treatment prior to SEG leads to electrical characteristics with less dependence on bias voltage. The IC consists of a receiver (a preamplifier, an automatic gain control (AGC) amplifier, a phase-locked loop (PLL), and a D-type flip-flop (D-F/F)), and a 1:16 demultiplexer (DMUX). An input offset control circuit is included in the AGC amplifier for wide dynamic range. Trench isolation and silicon-on-insulator (SOI) technologies are introduced to reduce crosstalk between the amplifiers and the PLL. Power consumptions are 0.6 W at -5.2 V for the analog part and 0.45 W at -3.3 V for the digital part, which does not include the ECL output buffers     

Differential CMOS circuits for 622-MHz/933-MHz clock and datarecovery applications

This paper describes the architecture and components of a high-speed clock and data recovery (CDR) circuit. Fully differential CMOS circuits are presented for an integrated physical layer controller of a 622-Mb/s (OC-12) system, although the design can be used in other systems with clock speeds in the 622-933-MHz range. Simulations and experimental results are presented for the building blocks including novel designs for a current-controlled oscillator (CCO) and a differential charge pump. The CCO is based on a two-stage ring oscillator. It consists of parallel differential amplifier pairs which reliably generate the necessary phase shift and gain to fulfill the oscillation conditions over process and temperature variations. Two test chips are implemented in 0.35-μm CMOS. One contains partitioned building blocks of a phase-locked loop (PLL) which, together with an external loop filter, can be used for flexible testing and CDR applications. The other chip is a monolithic CDR with integrated loop filter. It exhibits a power consumption of 0.2 W and a measured rms clock jitter of 12.5 ps at 933 MHz     

一个简单鉴频鉴相器结构实现的快速锁定低抖动锁相环

用简单的鉴频鉴相器结构实现了一个快锁定低抖动的锁相环.鉴频鉴相器仅仅由两个异或门组成,它可以同时获得低抖动和快锁定的性能.锁相环中的电压控制振荡器由四级环形振荡器来实现,每级单元电路工作在相同的频率,并提供45°的相移.芯片用0.18μm CMOS工艺来实现.PLL输出的中心频率为5GHz,在偏离中心频率500kHz处,测量的相位噪声为-102.6dBc/Hz.锁相环的捕获范围为280MHz,RMS抖动为2.06ps.电源电压为1.8V时,功耗仅为21.6mW(不包括输出缓冲).     

A 2.5-3.125-Gb/s quad transceiver with second-order analog DLL-based CDRs

This paper describes a 2.5-3.125-Gb/s quad transceiver with second-order analog delay-locked loop (DLL)-based clock and data recovery (CDR) circuits. A phase-locked loop (PLL) is shared between receive (RX) and transmit (TX) chains. On each RX channel, an amplifier with user-programmable input equalization precedes the CDR. Retimed data then goes to an 1:8/1:10 deserializer. On the TX side, parallel data is serialized into a high-speed bitstream with an 8:1/10:1 multiplexer. The serial data is introduced off-chip through a high-speed CML buffer having single-tap pre-emphasis. Proposed DLL-based CDR can tolerate large frequency offsets with no jitter tolerance degradation due to its second-order PLL-like nature. Also, this study introduces an improved charge-pump and an improved phase-interpolator. Fabricated in a 0.15-/spl mu/m CMOS process, the 1.9-mm/sup 2/ transceiver front-end operates from a single 1.2-V supply and consumes 65-mW/channel of which 32 mW is due to the CDR. CDR jitter generation and high-frequency jitter tolerance are 5.9 ps-rms and 0.5 UI, respectively, for 3.125 Gb/s, 2/sup 23/-1 PRBS input data with 800-ppm frequency offset.     

Clock and data recovery IC for 40-Gb/s fiber-optic receiver

The integrated clock and data recovery (CDR) circuit is a key element for broad-band optical communication systems at 40 Gb/s. We report a 40-Gb/s CDR fabricated in indium-phosphide heterojunction bipolar transistor (InP HBT) technology using a robust architecture of a phase-locked loop (PLL) with a digital early-late phase detector. The faster InP HBT technology allows the digital phase detector to operate at the full data rate of 40 Gb/s. This, in turn, reduces the circuit complexity (transistor count) and the voltage-controlled oscillator (VCO) requirements. The IC includes an on-chip LC VCO, on-chip clock dividers to drive an external demultiplexer, and low-frequency PLL control loop and on-chip limiting amplifier buffers for the data and clock I/O. To our knowledge, this is the first demonstration of a mixed-signal IC operating at the clock rate of 40 GHz. We also describe the chip architecture and measurement results.     

光纤通信用低相位抖动时钟数据恢复电路

文章阐述了一种适用于光纤通信的锁相环(PLL)时钟数据恢复电路结构.该结构采用负阻放大形式构成二阶有源低通滤波器,并用PECL环形延时单元构成压控振荡器(VCO),工作在80 ～500 MHz的频率范围内,峰-峰相位抖动＜20 ps,锁定时间＜600 ns.实际电路在计算机上仿真成功,版图后仿真验证也已通过,并进行了投片.     

Jitter analysis and modeling of a 10 Gbit/s SerDes CDR and jitter attenuation PLL

Jitter analysis and a linear model is proposed in this paper which predicts the characteristics of serial-deserial(SerDes) clock and data recovery circuit,and the characteristics include jitter transfer,jitter tolerance and jitter generation are particularly analyzed.The simulation results of the clock data recovery(CDR) model show that the jitter specifications exceed the mask of ITU-T optical transport network(OTN) G.8251 recommendations.The whole systems are validated by 9.95-11.5 Gbit/s CDR and the jitter attenuation phase locked loops(PLL) circuits using TSMC 65 nm CMOS technology.     

A fully integrated SiGe receiver IC for 10-Gb/s data rate

A silicon germanium (SiGe) receiver IC is presented here which integrates most of the 10-Gb/s SONET receiver functions. The receiver combines an automatic gain control and clock and data recovery circuit (CDR) with a binary-type phase-locked loop, 1:8 demultiplexer, and a 2 ⁷-1 pseudorandom bit sequence generator for self-testing. This work demonstrates a higher level of integration compared to other silicon designs as well as a CDR with SONET-compliant jitter characteristics. The receiver has a die size of 4.5×4.5 mm2 and consumes 4.5 W from -5 V     

A low-jitter 125-1250-MHz process-independent and ripple-poleless0.18-μm CMOS PLL based on a sample-reset loop filter

This paper describes a low-jitter phase-locked loop (PLL) implemented in a 0.18-μm CMOS process. A sample-reset loop filter architecture is used that averages the oscillator proportional control current which provides the feedforward zero over an entire update period and hence leads to a ripple-free control signal. The ripple-free control current eliminates the need for an additional filtering pole, leading to a nearly 90° phase margin which minimizes input jitter peaking and transient locking overshoot. The PLL damping factor is made insensitive to process variations by making it dependent only upon a bandgap voltage and ratios of circuit elements. This ensures tracking between the natural frequency and the stabilizing zero. The PLL has a frequency range of 125-1250 MHz, frequency resolution better than 500 kHz, and rms jitter less than 0.9% of the oscillator period