SAW filter

youwin0125

http://www3.sympatico.ca/colin.kydd.campbell/
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這是基本的SAW filter 請問微帶線結構如何接上它 信號可以接 可是微帶線的地在背面 那SAW下面那一半要貫孔下去接地嗎
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2 u: m$ P1 [" c4 ?' `這是常用的SAW filter 請問有設計公式嗎 小弟想設計2.3GHz~2.6GHz 用FR4版材做
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萬分感謝

DennyT

工作上真的需要就花錢買來看看吧:
用PCB取代HTCC (高溫共燒陶瓷) 基板, 不過好像不是直接用銅箔蝕刻SAW, 因為它還是用了鉭酸鋰wafer及薄膜製程來構成SAW本體, 只是封裝結構捨棄HTCC, 直接mount在PCB上.
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直接用銅箔及FR4做成SAW應該沒辦法上到GHz吧, 看看PCB銅線蝕刻最小mm級pitch對上半導體製程的um或sub-um pitch, FR4 SAW能有百KHz就很厲害了吧, 上到MHz便可稱神人了.

http://ieeexplore.ieee.org/Xplor ... +Im%3B+Seunghee+Lee

  H- \9 r: {( FDevelopment of the RF SAW filters based on PCB substrate
Youngjin Lee; Jongin Im; Seunghee Lee
International Frequency Control Symposium and Exposition, 2006 IEEE
6 b* W% J; O, X6 `Volume , Issue , June 2006 Page(s):334 - 337
Digital Object Identifier   10.1109/FREQ.2006.275408

# p& ^* y) u" D) O. R3 p0 QSummary: Recently produced RF SAW (surface acoustic wave) filters are made using HTCC (high temperature cofired ceramic) with CSP (chip scale package) technology. This paper describes the development of a new 1.4 times 1.1 and 2.0 times 1.4 mm RF SAW filter based on PCB (printed circuit board) substrate instead of HTCC package, which reduces the cost of materials by 40%. We have investigated the multilayered PCB substrate structure and raw materials to determine the optimal flip-bonding condition between the LiTaO3 wafer and PCB substrates. Also, optimal materials and processing conditions for the epoxy laminating film were experimentally determined that can reduce the bending moment caused by thermal expansion differences between the PCB substrate and laminating film. The new PCB SAW filter shows better electrical and reliability performances than those observed with present SAW filters.