- 學位論文
使用交換式電容技術設計自動調整頻率濾波器
Design of Automatic-Frequency-Tuning Filter Based on Switched-Capacitor Techniques
摘要
本論文的研究重點可分為兩部分，第一部份: 設計一個電壓模式交換式電容可調濾波器，使用運算轉導放大器(Operational Transconductance Amplifier)當作電壓模式主動元件，藉由線性轉換的方式達到高階主動低通濾波器，然而控制開關的責任週期(Duty Cycle)來達到頻寬調整的功能。本晶片是採用TSMC 0.18 μm 1P6M CMOS製程。濾波器可調整的頻寬範圍為8MHz至20MHz，濾波器的功率消耗為12.3mW，整體晶片面積為0.45mm×0.4mm (不含PADs)。 第二部份:設計一個自動頻率調整系統(Automatic-Frequency-Tuning system)，利用交換式電容技術設計四階可調巴特沃斯濾波器，藉由控制開關的責任週期來達到頻寬調整的功能。為了避免製程中所產生的變異，亦在晶片上設計一個可自動調整頻率系統用來自動補償頻寬的變異，已達到所要求的濾波器效能。因此，一般傳統的自動調整頻率系統使用主從式架構，本文採用單一濾波器進而做調整。本晶片是採用TSMC 0.18 μm 1P6M CMOS製程。濾波器可調整的頻寬範圍為1MHz至4MHz，電源電壓為1.8V，濾波器的功率消耗為15.2mW，整體晶片面積為0.57mm×0.5mm (不含PADs)。
並列摘要
The major research of this thesis can be divided into two sections. The proposed tunable Butterworth filter utilizes the switched-capacitor techniques in first section. This thesis utilizes operational transconductance amplifier as the voltage-mode active elements. Therefore, according to the linear transformation, high-order active low pass filter is achieved. Therefore, the bandwidth is tuned by the duty cycle of control switches. The proposed circuit is fabricated by TSMC 0.18μm 1P6M CMOS process. The tunable bandwidth of filter is from 5MHz to 20MHz. The power consumption is 12.3mW, and the chip area without I/O PADs is 0.45mm×0.4mm. This thesis designs an automatic-frequency-tuning system in second section. A fourth-order tunable Butterworth filter is designed by the switched-capacitor techniques. The filter bandwidth is tuned by the duty cycle of control switches. In order to avoid process variation, the on-chip automatic-frequency-tuning system is also designed to compensate the bandwidth variation. The conventional automatic-frequency-tuning system employs the master-slave scheme to control the filter frequency; however the proposed system uses a single switched-capacitor filter to tune the bandwidth. The proposed circuit is fabricated by TSMC 0.18μm 1P6M CMOS process. The tunable bandwidth of filter is from 1MHz to 4MHz. The power supply and power consumption are 1.8V and 15.2mW, respectively. The chip area without I/O PADs is 0.57mm×0.5mm.