DVB-T數位電視CMOS鎖相迴路電荷幫浦之設計

Abstract

本論文以 TSMC 0.18μm CMOS 1P6M 製程，來設計可應用於本地端振盪器之鎖相迴路。鎖相迴路中包含了相位頻率偵測器、電荷幫浦、迴路濾波器、壓控振盪器以及頻率除頻器。 在數位電視調諧器中寬頻鎖相迴路的規畫上，我們選擇了 1 MHz 的輸入參考頻率，系統的供應電壓為 1.8 V。相位頻率偵測器所採用的是具有可操作在高頻特性的相位頻率偵測器。電荷幫浦是具有快速交換速度的電荷幫浦，並且加上回授放大器來改進鎖定之後不匹配電流的問題。迴路濾波器方面，我們採用了二階的迴路濾波器，用來濾除原本會在壓控振盪器的控制電壓端所產生的高頻成分。壓控振盪器我們採用了具有良好相位雜訊特性的 LC – tank 壓控振盪器，它可調整的範圍為 2.486 GHz ~ 3.333 GHz 。

This thesis, based on tsmc 0.18um CMOS 1P6M process , PLL, is designed to apply to Local oscillator. PLL includes phase frequency detector、charge pump、loop filter、voltage control oscillator and frequency divider. In the design of DVB-T tuner , we have chosen the input 1MHz of reference frequency, with the system supply voltage at 1.8V. What phase frequency detector adopts is operational high-frequency. Charge pump possesses fast-switching speed, adding feedback amplifier to improve the problem of mismatched current . In terms of loop filter , we adopt two order loop filter to filter the high-frequency ingredient. Besides well-phase noise LC-tank VCO, its adaptability ranges from 2.486 GHz to 3.333 GHz .