Generation and Comparison of Three OTRA-Based Voltage-Mode Third-Order Elliptic Filter Structures

• Main Authors: Jen-chih Chung, 鍾任植
• Other Authors: Chun-Ming Chang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/65286849219773938839

碩士 === 中原大學 === 電機工程研究所 === 101 === This search is to realize third-order elliptic filter structures with admittance matrix analytical synthesis. The procedures go to: Firstly, to change the transfer function into three current equations; Secondly, to use the characteristics of OTRA (Operation Trans-Resistance Amplifier), resistors and capacitors for realizing three sub-circuits. Lastly, to synthesize sub-circuits for accomplishing third-order elliptic filter structures. In the process of circuit design, sub-circuits could synthesize to 27 circuits via the characteristics of OTRA. Each single circuit structure is made of 3 OTRA, 3 capacitors and 7 resistors. In the TSMC 0.35μm process by H-spice, only 3 of 27 circuits could work. According to the different arrangements of capacitors and resistors, the circuits are named in: 1. "3Cs in FB"- 3 capacitors in the feedback loop of OTRAs. 2. "3Rs in FB"- 3 resistors in the feedback loop of OTRAs. 3. "1C2Rs in FB"-1 capacitor and 2 resistors in the feedback loop of OTRAs. Then to compare the results, we find: when operating at 1MHz, “3Cs in FB” structure performs accurate fp. (Deviation at 0.23%) The results are caused by parasitical effect.