A GM-C filter Design Methodology for Mass Production

• Main Authors: Chien-Ping Hsueh, 薛建平
• Other Authors: Chung-Chih Hung
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/49037797903684203995

碩士 === 國立交通大學 === 電機學院碩士在職專班電信組 === 94 === In Chapter 1, there are some descriptions about the role of the IF filter in a communication system. Then, the motivation and the methodology to perform the research of the GM-C filter is presented. In Chapter 2, the fundamental theorem and functional blocks of the GM-C filter are introduced. After that, the possibility to compensate the fixed and variable errors is discussed. In Chapter 3, the author uses one 36MHz IF band-pass filter as reference design to study the corner effects and the temperature effects. Analyses and proves that the two variances of this filter can be compensated by using IC trimming skills and self-compensated bias circuits. In Chapter4, it is concluded that one can use the IC trimming skills to correct the center frequency error of the band-pass filter that is due to the IC process variance, and then use a self-compensation bias circuit to compensate the IC temperature effect. This design methodology is approved in this thesis, but a small error will exist due to the fact that this method is not an auto-feedback system, such as the auto-tuning method. This error will limit the application of the IF filter, but there are still lots of benefits in the low-Q IF filter design. The GM-C filter that is designed by this suggested methodology has a lot of benefits. These benefits are a) simple design method, b) very small IC area, c) low power consumption, d) no interference that exists in the auto-tuning system, and e) no need of an accurate reference frequency source. This method uses the IC trimming technology in the IC test, so the test cost will be increased. The center frequency detection system of band-pass filter will dominate the total test time in the IC tester. To design an excellent center frequency detection system will reduce the IC test cost. The purpose of the GM-C filter design methodology that is presented in this thesis provides another design possibility for GM-C filter mass production. There are some research areas that can be done following this design methodology. The research motivation and the theorems are introduced. The corner effect and temperature effect of the GM-C filter are then analyzed. Finally, this design methodology can be proved to be useful in low-Q IF filter design. The key point of this thesis is to provide an alternative for the mass production of IF band-pass filter design.