電子專業(yè)(畢業(yè)小論文外文資料及翻譯譯文(存儲(chǔ)版)
【正文】 e and the inverting input will approximate an ideal current source with value V/R.Inductor type current sourceAmongst other applications, the circuit of Figure 7 using the LM317 voltage regulator is used to present a source of constant current in Class E (switching) electronic amplifiers.Figure 7Current and voltage source parisonMost sources of electrical energy (mains electricity, a battery, ...) are best modeled as voltage sources. Such sources provide constant voltage, which means that as long as the amount of current drawn from the source is within the source39。也不能理想電壓源連接到一個(gè)理想的短路相關(guān)（r = 0），因?yàn)檫@將導(dǎo)致對(duì)有限非零元素上定義的電壓零電壓類似的悖論（短路）。這種理論的設(shè)備將有一個(gè)與源系列零歐姆的輸出阻抗。）電流鏡上的文章討論的另一個(gè)這些所謂的收益，例如，提高了電流鏡。 V時(shí)，補(bǔ)償二極管故障二極管通常不是必需的，因?yàn)閾舸C(jī)理是溫度依賴并不像它在上述這個(gè)電壓擊穿二極管的。因此，負(fù)載電流為常數(shù)（忽略了晶體管，由于早期的效果輸出電阻）和電路作為一個(gè)恒定電流源的運(yùn)作。一個(gè)增強(qiáng)型N溝道MOSFET，可用于下列電路簡(jiǎn)單晶體管電流源圖3顯示了一個(gè)典型的恒定電流源（CCS）的。例如，（177。連接的理想開路理想非零電流源是無效的，在電路的電路方程分析將是自相矛盾的，例如，5 = 0。相反，如果其他一些電壓或電路中的電流通過一個(gè)理想電流源的電流決定，它被稱為從屬或控制的電流源。附件1：外文資料翻譯譯文恒流源電流源是電氣或電子裝置，可提供或吸收電流。這些源符號(hào)，如圖2所示。沒有真正的電流源是理想的（不存在無限的能源），并且所有的有限的內(nèi)部電阻（沒有人能提供無限的電壓）。 5％），以在50至450歐姆負(fù)載電阻范圍。 DZ1是一個(gè)齊納二極管，當(dāng)這種反向偏置（所示電路），它有一個(gè)恒定的電壓上，不論是流經(jīng)它的電流下降。只要溫度保持不變（或變化不大），負(fù)載電流將是電源電壓，R1和晶體管的增益無關(guān)。簡(jiǎn)單晶體管電流源與LED另一種方法是取代輕齊納二極管的發(fā)光二極管LED1，如圖5。反饋也被用于兩個(gè)晶體管發(fā)射極電流鏡變性。一個(gè)真正的世界電壓源具有非常低的，但不為零輸出阻抗：通常遠(yuǎn)小于1歐姆。由于沒有理想的品種或來源存在（所有現(xiàn)實(shí)世界的例子有限和非零源阻抗），任何電流源，可作為具有相同的源阻抗，反之亦然電壓源考慮。s capabilities, its output voltage stays constant. An ideal voltage source provides no energy when it is loaded by an open circuit (. an infinite impedance), but approaches infinite power and current when the load resistance approaches zero (a short circuit). Such a theoretical device would have a zero ohm output impedance in series with the source. A realworld voltage source has a very low, but nonzero output impedance: often much less than 1 ohm.Conversely, a current source provides a constant current, as long as the load connected to the source terminals has sufficiently low impedance. An ideal current source would provide no energy to a short circuit and approach infinite energy and voltage as the load resistance approaches infinity (an open circuit). An ideal current source has an infinite output impedance in parallel with the source. A realworld current source has a very high, but finite output impedance. In the case of transistor current sources, impedances of a few megohms (at DC) are typical.An ideal current source cannot be connected to an ideal open circuit because this would create the paradox of running a constant, nonzero current (from the current source) through an element with a defined zero current (the open circuit). Nor can an ideal voltage source be connected to an ideal short circuit (R=0), since this would result a similar paradox of finite non zero voltage across an eleme
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