【摘要】：振蕩器是許多電子系統(tǒng)的重要組成部分,廣泛應(yīng)用于微電子系統(tǒng)電路中。電感電容振蕩器的面積較大,增加了芯片的成本,且不易集成；環(huán)形振蕩器的輸出頻率偏差較大,易受工藝、電源電壓以及溫度的影響。因此,設(shè)計一種能夠?qū)崿F(xiàn)全集成并且輸出穩(wěn)定的CMOS振蕩器已經(jīng)成為研究的熱點。論文的主要工作是設(shè)計一款以環(huán)形振蕩器為基礎(chǔ)帶有閉環(huán)自動頻率控制電路的全集成振蕩器,其頻率穩(wěn)定度取決于頻率電壓轉(zhuǎn)化器以及參考電壓。論文介紹了振蕩器的基本工作原理、性能指標(biāo),詳細(xì)分析了全集成振蕩器的整體架構(gòu)。本文設(shè)計了一種高精度的頻率電壓轉(zhuǎn)換器,通過在充電電容和采樣開關(guān)之間增加源極跟隨器以及使用基于運放負(fù)反饋的電平移位電路,提高了輸出頻率穩(wěn)定度。另一方面,考慮到噪聲的影響,需要降低環(huán)形振蕩器的靈敏度,本文設(shè)計了一種以開關(guān)電容陣列為負(fù)載的環(huán)形振蕩器結(jié)構(gòu)。論文中提出的高穩(wěn)定度振蕩器減少了電容的使用,達(dá)到了片上全集成的目的。本文基于SMIC0.18μmCMOS工藝,完成了電路及版圖的設(shè)計,并進(jìn)行了前后仿真驗證。后仿真結(jié)果表明本文設(shè)計的全集成振蕩器在電源電壓變化范圍為1.65-1.95V,溫度變化范圍為-20～100℃的情況下,其輸出頻率穩(wěn)定度可達(dá)到433MHz±4MHz,相位噪聲小于-98dBc/Hz@1MHz,1.8V的電源電壓下消耗的電流小于1.6mA,滿足設(shè)計指標(biāo)要求。
[Abstract]:Oscillator is an important part of many electronic systems and is widely used in microelectronic system circuits. The inductance capacitor oscillator has a large area, which increases the cost of the chip and is difficult to integrate. The output frequency deviation of the ring oscillator is large, which is easy to be affected by the process, power supply voltage and temperature. Therefore, the design of a fully integrated and output stable CMOS oscillator has become a hot topic. The main work of this paper is to design a fully integrated oscillator with closed loop automatic frequency control circuit based on ring oscillator. Its frequency stability depends on the frequency voltage converter and the reference voltage. The basic working principle and performance index of the oscillator are introduced in this paper, and the whole architecture of the full integrated oscillator is analyzed in detail. In this paper, a high precision frequency and voltage converter is designed. By adding the source follower between the charging capacitor and the sampling switch and using the level shift circuit based on the negative feedback of the operational amplifier, the output frequency stability is improved. On the other hand, considering the effect of noise, the sensitivity of ring oscillator should be reduced. In this paper, a ring oscillator with switched capacitor array as the load is designed. The high stability oscillator proposed in this paper reduces the use of capacitors and achieves the purpose of full integration on a chip. Based on SMIC0.18 渭 mCMOS process, the circuit and layout are designed and verified by simulation. The simulation results show that the output frequency stability of the fully integrated oscillator can reach 433MHz 鹵4 MHz when the voltage range is 1.65-1.95 V and the temperature range is -20 鈩，

本文編號：2365022