Kwanseo Park

A 7.6 mW, 414 fs RMS-Jitter 10 GHz Phase-Locked Loop for a 40 Gb/s Serial Link Transmitter Based on a Two-Stage Ring Oscillator in 65 nm CMOS

This paper describes the design of a 10 GHz phase-locked loop (PLL) for a 40 Gb/s serial link transmitter (TX). A two-stage ring oscillator is used to provide a four-phase, 10 GHz clock for a quarter-rate TX. Several analyses and verification techniques, ranging from the clocking architectures for a 40 Gb/s TX to oscillation failures in a two-stage ring oscillator, are addressed in this paper. A tri-state-inverter-based frequency-divider and an AC-coupled clock-buffer are used for high-speed operations with minimal power and area overheads. The proposed 10 GHz PLL fabricated in the 65 nm CMOS technology occupies an active area of 0.009 mm2 with an integrated-RMS-jitter of 414 fs from 10 kHz to 100 MHz while consuming 7.6 mW from a 1.2-V supply. The resulting figure-of-merit is -238.8 dB, which surpasses that of the state-of-the-art ring-PLLs by 4 dB.

A 0.36 pJ/bit, 0.025 mm 2 , 12.5 Gb/s Forwarded-Clock Receiver With a Stuck-Free Delay-Locked Loop and a Half-Bit Delay Line in 65-nm CMOS Technology.

This paper describes a power and area-efficient forwarded-clock (FC) receiver and includes an analysis of the jitter tolerance of the FC receiver. In the proposed design, jitter tolerance is maximized according to the analysis by employing a delay-locked loop (DLL) based de-skewing. A sample-swapping bang-bang phase-detector (SS-BBPD) eliminates the stuck locking caused by the finite delay range of the voltage-controlled delay line (VCDL), and also reduces the required delay range of the VCDL by half. The proposed FC receiver is fabricated in 65-nm CMOS technology and occupies an active area of 0.025 mm2. At a data rate of 12.5 Gb/s, the proposed FC receiver exhibits an energy efficiency of 0.36 pJ/bit, and tolerates 1.4-UIpp sinusoidal jitter of 300 MHz.

A 0.36 pJ/bit, 12.5 Gb/s forwarded-clock receiver with a sample swapping scheme and a half-bit delay line

A 12.5Gb/s forwarded clock receiver based on a DLL with a bang-bang PD is presented. The stuck locking is detected and averted by swapping edge and data samples at the output of the PD. Moreover, required delay range of the VCDL is reduced by half with the proposed sample swapping scheme. The prototype chip exhibits the power efficiency of 0.36pJ/bit and occupies 0.025mm2. Due to the wide jitter tracking bandwidth of DLL and the inherent jitter correlation between data and forwarded clock, the proposed receiver exhibits outstanding jitter tolerance whose corner frequency is higher than 300 MHz.

A 10 Gb/s hybrid PLL-based forwarded clock receiver in 65-nm CMOS

A 10 Gb/s PLL-based forwarded clock receiver is implemented in 65-nm CMOS technology. The proposed architecture uses a hybrid PLL-based deskew which is combined with a PLL and a DLL. The PLL provides jitter filtering and the DLL performs deskewing by shifting the divided clocks. Since the operating frequency of the DLL is low, the power consumption of the DLL can be reduced. The measurement results show that the rms jitter of the recovered clock is only 576.7 fs which is quite low for a ring-oscillator-based PLL. The receiver chip occupies an active area of 0.0136 mm2 and consumes 22.1 mW at the data rate of 10 Gb/s.

A 7.6 mW, 214-fs RMS jitter 10-GHz phase-locked loop for 40-Gb/s serial link transmitter based on two-stage ring oscillator in 65-nm CMOS

This paper presents a -245.3 dB FoMJ phase-locked loop based on a ring oscillator and a novel analysis on 2-stage ring oscillator. The proposed PLL generates a 4-phase 10-GHz clock for a 40-Gb/s serial link transmitter. The proposed analysis offers a time-domain insight on 2-stage ring oscillator and a precise prediction on oscillator behavior such as an output frequency and whether the 2-stage ring oscillates or not, based on a simple open-loop approach with a single stage buffer. The prototype chip is fabricated in 65-nm CMOS technology, and the PLL occupies only 0.009 mm2 and dissipates 7.6 mW from 1.2-V supply and 9 mW from 1.3-V supply. The measured integrated jitter of the PLL is 214 fs from 1.2-V supply and 182 fs from 1.3-V supply, which corresponds to -244.6 dB and -245.3 dB FoMJ, respectively.

A 27.1 mW, 7.5-to-11.1 Gb/s single-loop referenceless CDR with direct Up/dn control

A 7.5-to-11.1 Gb/s half-rate referenceless clock and data recovery (CDR) with a compact frequency acquisition scheme is proposed. Using the bang-bang phase-frequency detector with a direct up/dn control, the referenceless CDR is realized by a single-loop architecture which performs both phase and frequency acquisition in the same loop. The proposed frequency acquisition scheme achieves a wide capture range of 3.6 Gb/s and reduces cycle-slips. The proposed CDR is fabricated in 65-nm CMOS technology and occupies an active area of 0.04 mm2. At the data rate of 10 Gb/s, the proposed CDR consumes 27.1 mW from 1.3-V supply.

A 55.1 mW 1.62-to-8.1 Gb/s Video Interface Receiver Generating up to 680 MHz Stream Clock Over 20 dB Loss Channel

A 1.62-to-8.1 Gb/s video interface receiver with an adaptive equalizer and a stream clock generator (SCG) is proposed. The adaptation logic is achieved by an edge-based adaptation and it controls the continuous-time linear equalizer ac boost. Using the adaptation logic, the minimum BER point is selected for several cables. The SCG consists of a phase-switching fractional divider and a delta–sigma modulator. The dividing factor is determined by the display resolution and the SCG operates up to 680 MHz which is the 4K UHD pixel frequency. The proposed receiver is fabricated in 65-nm CMOS technology and occupies an active area of 0.282 mm2. The measured BER is less than

A 6-to-32 Gb/s voltage-mode transmitter with scalable supply, voltage swing, and pre-emphasis in 65-nm CMOS

10^{-12}

A Supply-Scalable-Serializing Transmitter With Controllable Output Swing and Equalization for Next-Generation Standards

with a 20-ft-long video cable, whose insertion loss at 4.05 GHz is 20 dB. The receiver consumes 55.1 mW at the data rate of 8.1 Gb/s.

A 2.44-pJ/b 1.62–10-Gb/s Receiver for Next Generation Video Interface Equalizing 23-dB Loss With Adaptive 2-Tap Data DFE and 1-Tap Edge DFE

A voltage-mode (VM) transmitter which offers a wide operation range of 6-to-32 Gb/s, controllable pre-emphasis equalization and output voltage swing without altering output impedance, and a power supply scalability is presented. A quarter-rate clocking architecture is employed in order to maximize the scalability and energy efficiency across the various operating conditions. A P-over-N VM driver is used for CMOS compatibility and wide voltage-swing range required for various I/O standards. Two supply regulators calibrate the output impedance of the VM driver across the wide swing and pre-emphasis range. A single phase-locked loop is used to provide a wide frequency range. The prototype chip is fabricated in 65-nm CMOS technology and occupies active area of 0.48×0.36 mm2. The proposed transmitter achieves 250-to-600-mV single-ended swing and exhibits the energy efficiency of 2.10-to-2.93 pJ/bit across the data rate of 6-to-32 Gb/s.