本文提出兩種全差動式五階低通轉導電容濾波器架構，並設計符合此新式濾波器架構的運算轉導放大器電路，分別為多輸入差動輸出運算轉導放大器(MIDO OTA)、電流映對輸出差動輸入運算轉導放大器(CMDI OTA)與多輸出差動輸入運算轉導放大器(MODI OTA)。
以CMDI OTA與MODI OTA為基礎所建構的五階低通轉導電容濾波器電路比其它濾波器電路有較好的效能，較小的硬體面積及較低功率消耗。模擬結果顯示此濾波器的動態範圍為51.2dB，在差動輸入訊號振幅為100mVp-p下，其諧波失真成份低於-50dB。此濾波器在供應電壓1V下，所需的功率消耗低於320nW，其晶片的核心面積為0.176 mm2。此晶片為台灣積體電路製造公司的0.18μm製程所製作而成。量測結果顯示此低電壓低功率濾波器的動態範圍為30.5dB，在差動輸入訊號振幅為60mVp-p下，其總諧波失真低於-40dB。而測試結果顯示此濾波器頻寬為100Hz並且可以濾除掉腦波訊號頻率以外的雜訊干擾。

In this thesis, two kinds of fifth-order differential Gm-C low pass filters are presented. Three operational transconductance amplifiers (OTAs) are employed to realized the filters, namely, the multiple-input-differential-output
(MIDO) OTA, the current-mirror-output-differential-input (CMDI) OTA, and the multiple-output-differential-input (MODI) OTA.
The fifth-order OTA-C low pass filter was micro-fabricated by using the CMDI and MODI OTA design which required smaller area of die and lower power consumption. The simulated results showed a dynamic range of 51.2dB, while harmonic distortion components were below -50dB for differential input signals up to 100mV peak to peak (Vp-p). The power consumption of this filter was below 320nW, the supply voltage was 1V, and the active area of die was 0.176 mm2. This chip was fabricated with 0.18-μm CMOS process in TSMC. The measured results indicated that this low-voltage and low-power filter possessed the dynamic range of 30.5dB, while total harmonic distortion was less than -40dB for 60mVp-p input. According to the testing results, this filter can be adopted to eliminate the out-of-band interference of the electroencephalography (EEG) whose signal bandwidth is below 100Hz.

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