【正文】 源。開關式電源，開關電源，開關穩(wěn)壓器，并指這種類型的電力供應。 最現(xiàn)代化的臺式和筆記本電腦已經(jīng)有一個DCDC轉換器在主板上，電壓從電源或電池送往核心CPU， V，~。 最后，輸入電流等基本開關式電源的高次諧波含量和相對較低的功率因數(shù)。這部分的電力供應被稱為開關穩(wěn)壓器。 經(jīng)過整流后的電壓輸出較平滑，然后通過一個電感器和電容器組成的過濾器。輸出電壓是光耦合輸入，從而可以非常嚴格的控制。整流電路可配置一個電壓倍增，增加了一個開關操作手動或自動。 they have the advantages of faster recovery times than silicon diodes (allowing lowloss operation at higher frequencies) and a lower voltage drop when conducting. For even lower output voltages, MOSFETs may be used as synchronous rectifiers。其他優(yōu)勢包括更小的尺寸和較輕的重量（從消除低頻變壓器具有高體重）和低熱量的產(chǎn)生，還有更高的效率。然而，這種類型的使用可能有害整流階段，因為它只能利用二極管整流的滿負荷的一半。這種轉換的電壓上升或下降到所需的輸出電平可在其二次繞組。這一類的轉換器有許多的變化和擴展，但是這三種形式都是基于幾乎所有的隔離和非隔離式DC直流轉換器。大部分的線性電源成本節(jié)?。ㄓ止?jié)省空間）在來自這樣一個事實，即高頻變壓器使用的頻率是遠小于50/60赫茲。的能量轉換器輸出，并切換開啟和關閉發(fā)生在零電流和電壓，導致基本上無損開關。有些被轉換成400赫茲交流電源和28 V直流電源。大卡車使用24伏直流電。較高開關頻率允許元件尺寸縮小，但遭受的射頻（ RF ）性能另一方面。首先低頻變壓器傳輸能量通常通過其核心（軟鐵） ，而（通常鐵氧體）核心的高頻變壓器限制泄漏。其他類型的開關模式電源是使用電容二極管電壓倍增而不是電感器和變壓器。輸出電壓為10伏或10V以上的話，常用普通硅二極管。 如果開關電源在輸入范圍內(nèi)使用，整流器階段通常配置一個電壓補償作業(yè)時的低電壓（~120VAC）范圍和作為直整流作業(yè)時的高電壓（~240VAC）的范圍。 有關術語的說明雖然“電源一詞”開始出現(xiàn)于無線電的供電線路/主干線，這并不意味著它是力量的源泉，而是作為一個電池提供電源。 typically several secondaries feed rectifiers, series inductors, and filter capacitors to provide various DC outputs with low ripple.The main advantage of this method is greater efficiency because the switching transistor dissipates little power in the saturated state and the off state pared to the semiconducting state (active region). Other advantages include smaller size and lighter weight (from the elimination of low frequency transformers which have a high weight) and lower heat generation due to higher efficiency. Disadvantages include greater plexity, the generation of high amplitude, high frequency energy that the lowpass filter must block to avoid electromagnetic interference (EMI), and a ripple voltage at the switching frequency and the harmonic frequencies thereof.A note about terminologyAlthough the term power supply has been in use since radios were first powered from the line/mains, that does not mean that it is a source of power, in the sense that a battery provides power. It is simply a device that (usually) accepts mercial AC power and provides one or more DC outputs. It would be more correctly referred to as a power converter, but long usage has established the term.ClassificationSMPS can be classified into four types according to the input and output waveforms:AC in, DC out: rectifier, offline converter input stage DC in, DC out: voltage converter, or current converter, or DC to DC converter AC in, AC out: frequency changer, cycloconverter, transformer DC in, AC out: inverterInput rectifier stageIf the SMPS has an AC input, then the first stage is to convert the input to DC. This is called rectification. The rectifier circuit can be configured as a voltage doubler by the addition of a switch operated either manually or automatically. This is a feature of larger supplies to permit operation from nominally 120 volt or 240 volt supplies. The rectifier produces an unregulated DC voltage which is then sent to a large filter capacitor. The current drawn from the mains supply by this rectifier circuit occurs in short pulses around the AC voltage peaks. These pulses have significant high frequency energy which reduces the power factor. Special control techniques can be employed by the following SMPS to force the average input current to follow the sinusoidal shape of the AC input voltage thus the designer should try correcting the power factor. An SMPS with a DC input does not require this stage. An SMPS designed for AC input can often be run from a DC supply (for 230V AC this would be 330V DC), as the DC passes through the rectifier stage unchanged. It39。分類 開關電源可分為四種類型根據(jù)輸入和輸出波形： 交流——直流：整流器，離線轉換器輸入級 直流——直流：電壓轉換器，或電流轉換器，或直流對直流轉換器 交流——交流：變頻器，變頻，變壓 直流——交流：逆變器 輸入整流器階段 如果有一個開關電源AC輸入，然后在第一階段把交流變成直流輸出。逆變階段逆變直流轉換階段，無論是直接輸入或從整流階段輸入，要變?yōu)榻涣餍枰ㄟ^一個電源振蕩器，其輸出變壓器有很少的繞組，頻率為幾十或幾百千赫（