本論文中，使用0.35 微米二層多晶矽四層金屬之互補式金氧半製程，提出一個兼具有線性度與數位可調之轉導放大器。為了使此轉導放大器能夠兼具數位可調功能與信號線性度要求，在轉導放大器的設計中融合了數位可調式電流鏡與適應性偏壓差動對。數位可調式電流鏡接受數位控制訊號，以改變轉導放大器整體電路之轉導值，而適應性偏壓將改善轉導放大器本體之訊號線性度。本論文為了驗證其線性度與數位可調轉導之功能，將其應用於二階帶通濾波器的設計。
在電路模擬方面，經由HSPICE輔助設計軟體驗證結果。此兼具有線性度與數位可調之轉導放大器，在取樣頻率50 MHz輸入訊號10 MHz下訊號對雜訊及失真比(Signal to noise and harmonic distortion ratio, SNDR )為61 dB，採用線性數位轉導放大器所建構之二階帶通濾波器，於輸入訊號為9 MHz混合10 MHz，其三階交互調變(third-order intermodulation, IM3)為56 dB。

In this thesis, a linearity improved and digitally programmable operational transconductance amplifiers (OTA) for Gm-C filter has been designed and implemented in a 0.35-µm 2P4M CMOS process. In order to improve the linearity of OTA, we used an adaptive biasing technique. In addition, the transconductance of OTA can be controlled by our proposed digitally programmable current mirror technique. A second-order bandpass filter was designed to verify the linearity and transconductance of OTA by using our proposed techniques.
The digitally programmable OTA has been simulated by circuit simulator, HSPICE. While the sampling frequency and input frequency are 50 MHz and 10 MHz respectively, the signal-to-noise and distortion ratio (SNDR) of the digitally programmable OTA is 61 dB. In our bandpass filter, the specification of 56-dB third-order intermodulation (IM3) was also achieved with input frequency mixed 9 MHz and 10 MHz.

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