翻訳と辞書 Words near each other ・ Bias blind spot ・ Bias Boshell ・ Bias Brahmin ・ Bias distortion ・ Bias Fortes ・ Bias frame ・ Bias in education ・ Bias in Mental Testing ・ Bias incident ・ Bias knitting ・ Bias of an estimator ・ Bias of Priene ・ BIAS Peak ・ Bias ratio ・ Bias tape ・ Bias tee ・ Bias, Landes ・ Bias, Lot-et-Garonne ・ Bias, West Virginia ・ Bias-free communication ・ Biasabad-e Now Sazi ・ Biasca ・ Biasca railway station ・ Biasca–Acquarossa railway ・ Biase ・ Biased Competition Theory ・ Biased graph ・ Biased random walk on a graph ・ Biashush ・ Biasi Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Bias tee ： ウィキペディア英語版 Bias tee A bias tee is a three port network used for setting the DC bias point of some electronic components without disturbing other components. The bias tee is a diplexer. The low frequency port is used to set the bias; the high frequency port passes the radio frequency signals but blocks the biasing levels; the combined port connects to the device, which sees both the bias and RF. It is called a ''tee'' because the 3 ports are often arranged in the shape of a T. ==Design== Conceptually, the bias tee can be viewed as an ideal capacitor that allows AC through but blocks the DC bias and an ideal inductor that blocks AC but allows DC. Although some bias tees can be made with a simple inductor and capacitor, wideband bias tees are considerably more complicated because practical components have parasitic elements. Bias tees are designed for transmission line environments. Typically, the characteristic impedance ''Z0'' will be 50 ohms or 75 ohms. The impedance of the capacitor (XC) is chosen to be much less than ''Z0'', and the impedance of the inductor (XL) is chosen to be much greater than ''Z0''. :$X\_C\; =\; =\; \backslash \; ;\; \backslash \; X\_L\; =\; j\; \backslash omega\; L\; =\; j\; 2\; \backslash pi\; f\; L$ Where ''ω'' is the frequency in radians per second and ''f'' is the frequency in hertz. Bias tees are designed to operate over a range of signal frequencies. The reactances are chosen to have minimal impact at the lowest frequency. For wide range bias tees, the inductor must be large at the lowest frequency. A large inductor will have a stray capacitance (which creates its self-resonant frequency). At a high enough frequency, the stray capacitance presents a low impedance shunt path for the signal, and the bias tee becomes ineffective. Practical wide band bias tees must use circuit topologies that avoid the shunt path. For example, a Picosecond Pulse Labs 5580 works from 10 kHz to 15 GHz. Consequently, the simple design would need an inductance of at least 800 μH (''XL'' about ''j''50 ohms at 10 kHz), and that inductor must still look like an inductor at 15 GHz. However, a commercial 820 μH inductor has a self-resonant frequency of only 1.8 MHz—four orders of magnitude too low.〔(Tamura surface mount inductor at DigiKey )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Bias tee」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.