應用於光通訊之時脈產生器與突發式時脈資料回復電路

Abstract

隨著科技的發展與進步，需要越來越大的資料傳輸量，高速長距離通訊系統，幾乎都採用光纖通訊技術來達到廣泛的應用，其中，發射器中的時脈產生器與接收器中的時脈資料回復電路，皆在光纖通訊系統扮演關鍵性角色。 在此篇論文，首先，介紹一應用於光纖通訊的38GHz 0.13um CMOS時脈產生器，它採用八相位電感電容壓控振盪器(8-phase LC VCO)，可以產生八個相位，高達38GHz輸出頻率的時脈訊號，論文中將會推導出，使用電容電感串接高通式架構，可以維持較高的頻率，並採用分布負載式除頻器(split-load frequency divider)，可以有效的增加除頻器的操作頻率，最後採用能降低相位誤差的相位偵測器(phase detector)，可以改善輸出的邊頻(frequency spur)。 第二，說明一應用於被動光纖網路(PON)通訊的34Gb/s 90nm CMOS 突發式時脈資料回復電路(burst mode CDR)。為了符合被動光纖網路多工控制的應用，它需要非常短的鎖定時間，為了減少依賴輸入資料產生的抖動(data dependent jitter)，並且產生高速的時脈，採用了電感電容閘式壓控振盪器(LC Gated VCO)，為了要接收寬頻的資料，採用一個寬頻輸入匹配電路以及一個寬頻資料緩衝器，最後採用相位選擇器，來預防因全速率(full-rate)操作下，可能產生的錯誤鎖定。 最後，除了完成以上光纖通訊關鍵電路，我們也提出一些可應用於未來的高速除頻器，高速除頻器一般採用注入鎖定式除頻器，因為可以產生最高的操作頻率以及較低的能量消耗。三種注入鎖定式除頻器，分別可以操作在72-78 GHz， 82.7-85.8GHz以及93.5~109.4GHz的範圍，論文中將會推導出，不同的架構，將會影響最高可操作的頻率以及可除頻範圍。

With the development and advancement of technology, the more and more data transmission quantity is needed. High-speed and long-distance communication systems mostly adopt the optical networks in various applications. The clock generator for transmitter and the clock data recovery (CDR) for receiver play the critical roles. First, a 38GHz clock generator in 0.13um CMOS is presented for optical communications. An 8-phase LC voltage-controlled oscillator is presented to generate the 8-phase 38GHz outputs. The highpass characteristic CL ladder topology sustains the high-frequency signals will be derived in this dissertation. The split-load divider is presented to extend the operation frequency. The phase detector (PD) improves the static phase error and improves the frequency spur. Second, a 34Gb/s burse-mode CDR in 90nm CMOS is presented for passive optical network (PON) communications. The PON is attracting in the point-to-multipoint communication systems. It needs very short settling time. To reduce the data jitter and generate the high-frequency output clock, the LC gated voltage-controlled oscillator is presented. To receive and transmit the broadband data, a wideband input matching circuit and a wideband data buffer are presented, respectively. The phase selector is proposed to overcome the false phase lock due to the full-rate operation. Finally, in addition to realize the above key components of optical communications, some high speed frequency divider is presented for future applications. The injection-locked frequency divider (ILFD) is attractive because the highest operation frequency and low power consumption. Three ILFDs have the locking range of 72-78 GHz, 82.7-85.8GHz and 93.5~109.4GHz, respectively. It will derive the center frequency and the locking range for different ILFDs.