本文選題：可編程增益放大器 + 共模反饋��； 參考：《東南大學(xué)》2015年碩士論文

【摘要】：全球數(shù)字廣播(Digital Radio Mondiale, DRM)和數(shù)字音頻廣播(Digital Audio Broadcasting, DAB)是世界范圍內(nèi)被廣泛應(yīng)用的數(shù)字廣播標(biāo)準(zhǔn)。研究基于這兩種標(biāo)準(zhǔn)的接收機(jī)芯片可以提升我國無線通信芯片的核心競爭力,具有重大意義。DRM接收芯片分為兩次變頻低中頻架構(gòu)。本文的研究對(duì)象是應(yīng)用于DRM/DAB接收機(jī)第二中頻(fc=2.048 MHz)的可編程增益放大器(Programable Gain Amplifier, PGA)和電流模復(fù)數(shù)帶通濾波器(Current-Mode Complex Band-Pass Filter)電路。PGA是保證接收機(jī)正常工作、具有較大輸入動(dòng)態(tài)范圍的重要模塊。本文的PGA采用的是基于運(yùn)(算)放(大器)的閉環(huán)反饋結(jié)構(gòu)。運(yùn)放是兩級(jí)全差分結(jié)構(gòu),采用密勒電容進(jìn)行相位補(bǔ)償。采用AB類輸出級(jí)來擴(kuò)大PGA的輸出動(dòng)態(tài)范圍和降低靜態(tài)功耗。另外,采用低增益的DCOC反饋回路來穩(wěn)定PGA的直流工作點(diǎn),同時(shí)保證反饋環(huán)路的穩(wěn)定性。PGA的工作帶寬大于10 MHz,增益范圍10～50 dB,步長l dB,帶內(nèi)增益波動(dòng)小于0.5 dB。當(dāng)增益為10 dB時(shí),IP1dB大于-5 dBm。本文的另一個(gè)主要工作是設(shè)計(jì)帶有鏡像頻率抑制功能的電流模濾波器。濾波器的輸入和輸出均為電流信號(hào)。文中的濾波器是一個(gè)3階切比雪夫Ⅰ型有源RC濾波器,其中心頻率為2 MHz,通帶帶寬1.6 MHz,帶內(nèi)波動(dòng)小于3 dB,鄰近信道抑制(ACS@6 MHz)和鏡像頻率抑制(IRR@ 2 MHz)大于35 dB。電流模濾波器的核心模塊是全差分電流放大器,該電流放大器采用第二代電流傳輸器CCⅡ(Current ConveyorⅡ)來實(shí)現(xiàn)。此外,設(shè)計(jì)中還引入了可編程電容陣列來實(shí)現(xiàn)濾波器的調(diào)諧。最后,采用中芯國際SMIC 0.18μm CMOS工藝實(shí)現(xiàn)了PGA和濾波器的電路,并進(jìn)行了流片測試。測試結(jié)果基本滿足設(shè)計(jì)指標(biāo)要求。同時(shí),分析了測試結(jié)果,對(duì)進(jìn)一步的工作提出了建議。
[Abstract]:Digital Radio broadcast (DRM) and Digital Audio Broadcasting (DAB) are widely used in the world. The research on the receiver chip based on these two standards can enhance the core competitiveness of the wireless communication chip in China. It is of great significance that the DRM receiver chip can be divided into two frequency conversion low intermediate frequency architectures. The research object of this paper is the programmable gain amplifier (PGA) and the Current-Mode complex Band-Pass filter (PGA) circuit, which are applied to the second intermediate frequency (fc=2.048 MHz) of DRM / DAB receiver. Important modules with large input dynamic range. The PGA in this paper adopts a closed loop feedback structure based on operational (computational) amplifier. The operational amplifier is a two-stage fully differential structure with Miller capacitor for phase compensation. Class AB output stage is used to expand the dynamic range of PGA output and reduce static power consumption. In addition, the DCOC feedback loop with low gain is used to stabilize the DC operating point of PGA. At the same time, the stability of the feedback loop. The bandwidth of PGA is larger than 10 MHz, the gain range is 1050 dB, the step is 1 dB, and the in-band gain fluctuation is less than 0.5 dB. When the gain is 10 dB, the IP 1dB is greater than -5 dBm. Another main work of this paper is to design a current-mode filter with mirror frequency suppression function. The input and output of the filter are current signals. The filter in this paper is a third-order Chebyshev type I active RC filter with a central frequency of 2 MHz, a passband bandwidth of 1.6 MHz, an in-band fluctuation of less than 3 dB, a proximity channel suppression (ACSR @ 2 MHz) and a mirror frequency suppression (IRR @ 2 MHz) of more than 35 dB. The core module of current-mode filter is fully differential current amplifier, which is implemented by current Conveyor 鈪，

本文編號(hào)：2085510