一种用于622Mb/s光纤通讯的时钟恢复电路

A Clock Recovery Circuit for 622-Mb/s Optical-Fiber Communication Systems

提出了一种用于622Mb/s光纤通讯系统的时钟恢复电路。该电路采用改善的正交相关器结构,以改善传统的锁相环捕获范围窄、因环境噪声干扰而失锁的问题。同时,很好地解决了数据恢复电路中时钟和数据的校准问题。压控振荡器(VCO)采用全差分和延时插入技术,以抑制电源和衬底噪声,提高振荡频率范围。该电路采用2μm双极型工艺,在3.3V电压下工作,用Cadence软件进行模拟,捕获时间小于16μs,输出时钟抖动小于0.005UI。

A clock recovery circuit for 622 Mb/s opticalfiber communication system is presented A modified architecture of quadricorrelator is adopted for the circuit, which enables acquisition to occur over a fairly wide rang and the alignment of clock and data at the input of the decision circuit In order to achieve high rejection of supply and substrate noises and broaden the range of oscillating frequency, fully differential and delay interpolation technology is used for the voltage controlled oscillator (VCO) Implemented in 2μm silicon bipolar process, the circuit operates at a low voltage of 33 V Simulation indicates that the acquisition lock time of the circuit is less than 16 μs and the clock output jitter is less than 0005 UI