201036312 六、發明說明： 【發明所屬之技術領域】 且特別是一種具有X電 本發明是有關於一種交流至直流轉換器 容的交流至直流轉換器。 【先前技術】 凡使用市肢流電的電子裝置，如液晶電視，—般需要交流至直 流轉換器來錯人之市歧㈣（其典魏如9G〜獅㈣轉換成高 壓準位的直流電壓（其典型值如珊〜撕），以提供直流至直流轉 換益將馬電壓準位電壓轉換成不同的低電壓準位（其典型值如⑽、 12V、5V)，以便提供用來操作電子裝置的電力電源。 圖1為-觀有的交流至直流轉換器之電路圖。請參照圖i，交 流至直流轉換器1包括電磁干擾(ElectIOMagnetic丨伽办⑽沈，簡 稱EMI)遽波益11、整流濾'波器12以及功率因數修正器（p〇werFact〇r torector ’簡稱PFC) 13。交流至直流轉換器丨從公共電網接收市用 交流電AC。市用交流電AC -般通過三條電源線來傳輸，即市用交流 電AC由火線（live Wire) L傳輸進入電子裝置，再經由零線(職㈣ V wire) N傳輸離開電子裝置，另外還通過將地線(earth wire)(圖中未 繪示)連接大地以避免電子裝置或人員遭漏電所傷。電子裝置通常在其 前端耦接至火線L或零線N的路徑上串接保險絲FU，以防止雷轚或大 電流燒毀内部電路。 / ΕΜΠ慮波器11用以抑制來自公共電網的電磁雜訊通過電源線傳入 電子裝置，同時也防止電子裝置本身產生的電磁雜訊通過電源線傳到 公共電網，其中電磁雜訊可分成差模(differential m〇de)雜訊及共模 (common mode)雜訊兩種。EMI濾波器11包括安規電容（safety capacitor) CX及兩共模電感LF1和LF2。安規電容CX跨接於火線l 201036312 及零線N之間’-般稱為χ電容，其用以滤除差模雜訊。兩共模電感 LF1和LF2為兩磁通方向相同的共模扼流線圈（ch〇ke c〇ils)，分別耦 接於X電容CX兩端及整流濾'波n 12之間，其用以絲共模雜訊。腿 濾波器11還包括放電電阻RX，其用以在市用交流電^被移除時，將 殘留在X電容CX上的電荷通過迴路P1洩放以防止人員觸電。此放電 電阻RX的電阻值通^很纽避免太彡電流從放電電阻狀流過而造成 太多功率損耗；然而，此放電電阻Rx的電阻值越大，將造成在市用交 流電AC被移除時’將_在x電容α上的電荷姐之速度越慢。 —依據IEC 60065安規規定，當市用交流電舵被移除時，殘留在X 電，CX上的電壓在2秒之内必須小於，。由於腿；慮波之需求，χ 電谷CX的電容值通常約在〇· 5uF〜2uF，而若要符合IEC 6〇〇65對於 市用交流電被移除時X電容朗電壓之安規規定，齡電電阻RX的電 阻值約在1ΜΩ〜250ΚΩ。因此’以歐規市用交流電AC之電壓23〇Vrms 為例’在市用父流電AC未被移除時，此放電電阻RX會有功率損耗約 為5jmW〜210mW。這對於目前通常要求待機模式(stand_by舶㈣下功 率損耗必射於1W或的電子裝置而言尚紐構成_。然而， 隨著越來越高的能源成本及全球變暖_，對於待機軸功率損耗要 求越來越嚴格，如待機功率損耗必須小於3〇〇mW或甚至必須小於⑽抓 的要求’财的交流至錢轉換II丨之放電電阻RX設計已不敷使用。 【發明内容】 ▲本發明的目的就是在提出—種使用功率因數修正器之具有X電容 =流至錢轉換n ’其在市較流絲被雜喊電電阻不會有功 =員耗’並在市用交流電被移除時可快速地$放殘留於x電容上的電 本發明的另-目的就是在提出—縣使用功率雜修正器之具有 201036312 流至直流轉換器，其在市时流絲被移 損耗’並在市用交流電被移除時可快速财放殘留於?= 正目的及其它目的’本發明提出-種使用功率因數修 汽=器交流至直流轉換器，其包括電磁干擾濾、波器、整 Ο201036312 VI. Description of the invention: [Technical field to which the invention pertains] and in particular to have an X-electricity The present invention relates to an AC to DC converter of an AC to DC converter capacity. [Prior Art] Where electronic devices using urban limb galvanism, such as LCD TVs, generally require AC to DC converters to misplace the market (4) (the DC voltage of the coded Wei as 9G ~ lion (four) converted to high voltage level (The typical value is like ~ tear) to provide DC to DC conversion to convert the horse voltage level voltage to different low voltage levels (typical values such as (10), 12V, 5V) to provide for operating the electronic device Figure 1 is a circuit diagram of an AC to DC converter. Please refer to Figure i. The AC to DC converter 1 includes electromagnetic interference (ElectIOMagnetic (10) sink, referred to as EMI). The filter 12 and the power factor corrector (p〇werFact〇r torector 'PFC for short) 13. The AC to DC converter receives the AC AC from the public grid. The AC AC is transmitted through three power lines. , that is, the commercial AC AC is transmitted into the electronic device by the live wire L, and then transmitted away from the electronic device via the neutral line (V) N, and also through the earth wire (not shown) ) big connection To avoid damage to the electronic device or personnel from electric leakage. The electronic device usually has a fuse FU connected in the path of its front end coupled to the live line L or the neutral line N to prevent the lightning or high current from burning the internal circuit. 11 is used to suppress electromagnetic noise from the public power grid from being transmitted to the electronic device through the power line, and also prevent electromagnetic noise generated by the electronic device from being transmitted to the public power grid through the power line, wherein the electromagnetic noise can be divided into differential modes. De) noise and common mode noise. EMI filter 11 includes safety capacitor CX and two common mode inductors LF1 and LF2. Safety capacitor CX is connected to fire line l 201036312 and neutral line N It is commonly referred to as tantalum capacitor, which is used to filter out differential mode noise. The two common mode inductors LF1 and LF2 are common mode choke coils with the same flux direction (ch〇ke c〇ils), respectively coupled Connected between the X capacitor CX and the rectifying filter 'wave n 12, which is used for common mode noise. The leg filter 11 further includes a discharge resistor RX, which is used when the commercial AC power is removed. The charge remaining on the X capacitor CX is discharged through the loop P1 to prevent The electric shock of the person. The resistance value of the discharge resistor RX is too strong to avoid too much power loss due to the current flowing from the discharge resistor. However, the larger the resistance value of the discharge resistor Rx, the AC current in the city. When removed, the slower the charge of the charge on the x-capacitor α. - According to the IEC 60065 safety regulations, when the commercial AC rudder is removed, it remains in X-electric, and the voltage on CX is 2 seconds. The inside must be less than. Because of the leg; the demand of the wave, the capacitance value of the electric valley CX is usually about u·5uF~2uF, and if it is to comply with IEC 6〇〇65, the X capacitor is the voltage for the commercial AC to be removed. The safety regulations stipulate that the resistance value of the electrical resistor RX is about 1 Μ Ω to 250 Κ Ω. Therefore, the voltage of the AC AC voltage of the European standard is 23 〇Vrms as an example. When the commercial parent current AC is not removed, the discharge resistor RX has a power loss of about 5 jmW to 210 mW. This is for the current standby mode (stand_by (four) power loss must be shot at 1W or the electronic device is still _. However, with higher energy costs and global warming _, for standby axis power The loss requirements are more and more strict, such as the standby power loss must be less than 3〇〇mW or even less than (10) the requirements of the 'carrying exchange to the money conversion II 放电 discharge resistance RX design is not enough. [Invention] ▲ this The purpose of the invention is to propose a type of power factor corrector that has X capacitance = flow to money conversion n 'there is no power in the city compared to the streamer is not active = member consumption ' and is removed in the city AC The other thing that can be quickly placed on the x-capacitor is to propose that the county uses a power miscorrector with a 201036312 flow-to-DC converter, which is lost in the city when the stream is lost. When the city's AC power is removed, it can be quickly and reliably released. = The purpose and other purposes. The present invention proposes to use a power factor repair steamer to an AC to DC converter, which includes an electromagnetic interference filter, a wave device, and a whole
用交流電。電磁干擾渡波器包括跨接於市用交流;==至市 ，規電容α-般稱為x電容)。整流濾波訌S3及間 第二端及第四端，整流滤波器第二端_至參考電位，整^ j塗 四端分_接至安規電容兩端，整流滤波器將市用ΐ流電轉 波器第一端輸出。功率因數修正器= 電。放電電路包括放電開關、放電電阻及檢測電路，放Use AC power. The electromagnetic interference waver includes a crossover to the commercial exchange; == to the city, the gauge capacitance α is commonly referred to as the x capacitor). The rectifying filter 讧S3 and the second end and the fourth end, the second end of the rectifying filter _ to the reference potential, and the four ends of the rectifying filter are connected to both ends of the safety capacitor, and the rectifying filter converts the commercial turbulent electric wave The first end of the output. Power factor corrector = electricity. The discharge circuit includes a discharge switch, a discharge resistor and a detection circuit.
Jit電電阻串聯轉接並跨接於整_波器第—端及參考電位之 二雷；^ I路输至整流舰11第三端或第四端以便在檢酬市用交 級電被移除時輸出檢測信號控制放電開關導通。 t達成上述目的及其它目的，本發明另提出-種未使用功率因 數^之具有X電容較流至直流賴ϋ，其包括電磁干擾遽波 器、整流濾波器以及放電電路。電磁干㈣妓，祕至交流^ , 電磁干㈣波器包括魏電容跨市肢流電之火線及零線之間。 整^慮波器，具有第m、第三端及第四端，整流遽波器第 -—接至參考電位，整流器第三端及第四端分顺接至安規電 容兩端，整麵波ϋ將市用錢電轉換為錢纏並通過整域波器 第-端輸出。放電電路，包括第—整流二極體、第二整流二極^^ 電開關:放電電阻及檢測電路，第—整流二極體陽極端祕至整流滤 波器第三端’第二整流二極體陽極端雛至整流濾波器第四端，第一 7 201036312 整流二極體陰極端耦接至第二整流二極體陰極端，放電開關及放電電 阻串聯耦接並跨接於第一整流二極體陰極端及參考電位之間，檢測電 路耦接至整流濾波器第三端或第四端以便在檢測到市用交流電被移除 時輸出檢測信號控制放電開關導通。 本發明在檢測到市用交流電被移除時’才控制放電電阻得以將殘 存在X電谷上的電荷洩放，因此在市用交流電未被移除時放電電阻不 會有功率損耗；再者，本發明放電電阻的電阻值不需要設計很大，故 在市用交流電被移除時可快速地洩放殘留在X電容上的電荷。 為讓本發明之上述和其他目的、特徵和優點能更明顯易懂，下文 特舉較佳實施例，並配合所附圖式，作詳細說明如下。 【實施方式】 圖2A及圖2B為依照本發明一實施例之使用功率因數修正器之具 有X電谷的父流至直流轉換器之電路圖，圖Μ及圖2β所示電路圖差 異僅在於以點線標示的迴路p21和ρ22不同。請同時參照圖Μ及圖 =本發明之交流至直流轉換器2包括電磁干擾(ΕΜΙ)濾波器21、整 =濾波器22、功率因數修正器（PFC) 23以及放電電路24。交流至直 "it轉換器2從公共電網接收市肢流電AC，且在其前_接至火線L 或零線N的路徑上串接保險絲FU，以防止雷擊或大電流燒毀内部電路。 濾波器21用以抑制來自公共電網的電磁雜訊通過電源線傳入 震置’同時也防止電子裝置本身產㈣電磁雜訊通過電源線傳到 電網。EMI濾波器21包括安規電容CX及兩共模電感Ln和^2。 各Q跨接於火線L及零線N之間’—般稱為χ電容，其用以渡 =^雜況。兩共模電感LF1和LF2為兩磁通方向相同的共模扼流線 刀別祕於X電容cx兩端及整流渡波器22之間，其用以滤除共 、…凡3外，EMI濾、波器21還可以包括其它的安規電容（圖中未繪 201036312 不）’例如雜於火線L及地線之間或跨接於零線N及地狀間的安 電容，一般稱為Y電容，其用以濾除共模雜訊。 整流滤波器22可以使用如圖1所示整流濾波器12之電路，其具 有第-端22卜第二端222、第三端223及第四端224。整流濾、波器22 第三端223及第四端224分別通過共模電感LF1和⑽輕接至χ電容 cx兩端，以接收濾除電磁雜訊的市用交流電AC。整流濾波器以第二 端222雛至參考電位GND ’整流渡波器22將市用交流電Ac轉 直流電壓並通過整流濾波器22第一端221輸出。 、 林實施射’ H級ϋ 22包括橋式整流ϋ及紐器。橋式整 〇流器由第一二極體DB卜第二二極體DB2、第三二極體及第四二極 體DB4四個二極體所組成，其中第一二極體脱陽極端及陰極端分別 耦接至整流濾波器22第四端224及第一端221，第二二極體DB2陽極 端及陰極端分別耦接至整流濾波器22第二端222及第三端223，第三 一極體DB3陽極端及陰極端分別耦接至整流濾波器22第三端2幻及第 端221苐四一極體DB4知極端及陰極端分別搞接至整流滅波器22 第二端222及第四端224。在另一實施例中，橋式整流器可 次側具有中間抽頭的變壓器及兩個二極體所組成，變壓器一次側兩端 Ο即為整流濾波器22第三端223及第四端224，兩個二極體陽極端分別 祕至變壓器二次侧兩端，兩個二極體陰極端皆搞接至整流滤波器22 第一端221，變壓器二次側中間抽頭耦接至整流濾波器22第二端四2。 在本實施例中，濾波器由濾波電容CB所組成，濾波電容⑶兩端跨接 於整流渡波器22第—端221及第二端222之間，用以降低整流滤波器 22第一端221輸出電壓之漣波，使整流濾波器22第一端221輸出較 穩定的直流電壓。在另一實施例中，濾波器可以是電感電容濾波器（如 LC濾波器）或π型濾波器（如CLC濾波器）。 但疋’整流渡波器22使用橋式整流器會造成市用交流電AC輪入 201036312 整流濾波器22的電流失真，一般通過在整流濾波器22後端加上pfc 來調整市用交流電AC輸入之電流波形以改善電流失真，尤其是功率在 75W以上的電子裝置目前都需要加上ρπ以符合譜波電流之規範。pp>c 23耦接至整流濾波器22第一端221及參考電位GND，並輸出高電壓準 位的直流電壓VBUS ’以提供直流至直流轉換器將高電壓準位之直流電 壓VBUS轉換成不同的低電壓準位之直流電壓，以便提供用來操作電子 裝置的電力電源。在本實施例中，PFC 23可以使用如圖i所示pFC 13 之電路，其採用主動式升壓型（b〇ost)直流至直流轉換器，故pFC 23 包括PFC驅動器UPFC、功率開關QPFC、電感LPFC、二極體〇pFC及電 容CPFC。PFC驅動器UPFC依據PFC 23輸出的直流電壓VBUS回授控制 功率開關QPFC的切換，在功率開關QPFC導通(〇N)時，輸入電能儲存 於電感LPFC而儲存於電谷CPFC的能量提供到輸出；在功率開關qpfc 斷開_)時，輸入電能及儲存於電感LpFC的能量提供到輸出，故 23工作時輸出典型值380〜400V的直流電壓VBUS。 放電電路24包括放電開關QDIS、放電電阻RDIS及檢測電路。老 電開關QDIS及放電電阻RDIS串聯柄接並跨接於整流滤波器烈第一綠 221及參考電位GND之間，檢測電路減至整流濾波器22帛三端怒 或第四端224以便在檢測到市用交流電AC被移除時輸出檢測 放電開關_導通。在本實施射，檢測f路包 檢 測驅動國T。檢難⑽具衫-觀第二端，檢測 =接至整流滤波器22第三端223 ;換句話說，檢測電容 接於整流毅器22第三端223及檢測驅動謂ΕΤ ^ 雜波器22第三端223的= 因市用父流電AC被移除而降低。 在整流濾波器22第 器UDET判斷市用交流電 三端223的電Μ降低到某一程度時，檢測驅動 AC被移除並輸出檢測信號控制放電開關卯κ 201036312 V通’一此時殘留在x電容cx上的電荷可通過圖2八所示迴路p2i或圖 2B所不，路P22來茂放。定義X電容cx兩端分別為第一端及第二端， 且^端搞接至零線N而第二端轉接至火線L。當X電容cx第一端電 位南於第二端電位時，殘留在X電容CX上的電荷通過圖2A所示迴路 P21j^放，此迴路P21由共模電感LF2、整流濾波器四第四端四4、 第a極體⑽1、整流滤波器22第一端221、放電電阻RDIS、呈導通 狀態的放電開關QDIS、參考電位gnd、整流濾、波器22第二端222、第 一一極體DB2、整流遽波器22第三端223及共模電感LF1所形成，其 是利f迴路中的放電電阻RDIS消耗掉殘留在χ電容α上的電荷。當 Ο X電谷CX第4電位低於第二端電位時，殘留在X電容上的電荷 通，圖2B所示迴路P22來敝，此迴路p22由共模電感Ln、整流遽 波器22第三端223、第三二極體聰、整流遽波器22第一端如、^ 電電阻RDIS、呈_狀態的放電開關綱s、參考電位⑽、整流遽波 器22第二端222、第四二極體DB4、整流濾波器22第四端似及 電感LF2所形成。 、、 由於在市用交流電AC未被移除時，放電開關哪斷開而使前述 迴路P21和P22斷路，故放電電阻_不會有功率祕；只有在侧 ❹到市用交流電AC被移除時，放電開關_才導通而使前述迴路p2i 和P22通路，放電電阻_得以消耗殘留在乂電容cx上的電荷；因 .此’本㈣交流至直_鋪2可符合待機轉損賴來峨格的要 求，如待機功率損耗必須小於15〇mW时求。另外，由於放電電阻聰 亚不是並聯輕接在X電容cx旁，故不需將放電電阻隨的電阻值設 計很大；換句話說，ffl 2A (或® 2B)所示放電電阻RDIS的電阻值可: 設計遠小於圖1所示放電電阻RX的電阻值，因此本發明交流至直 ^奐器2在市肢流電AC被移除時可快速地触殘留在χ f容上 荷，根據貫驗結果可在0. 5秒内使X電容上的電壓降為零。 201036312 * r 圖3為圖2A (或圖2B)所示檢測驅動器UDET之電路圖。請參照圖 3 ’檢測驅動器UDET包括整流二極體dd、第一電阻RD1、第二電阻Rj)2、 遽波電谷CD及驅動開關QDET。整流二極體DD陽極端輕接至檢測電容 CS第二端，第一電阻rdi及第二電阻RD2串聯耦接並跨接於整流二極 體DD陰極端及參考電位GND之間。濾波電容⑶兩端跨接於第一電阻 RD1及第一電阻RD2共同接點A及參考電位GND之間。驅動開關qdet 為回應第一電阻RD1及第二電阻肋2共同接點A上電壓下降至設定電 壓而輸出檢測信號，以控制放電開關qDIS導通。在本實施例中驅動 開關QDET為PNP雙載子接面電晶體，而放電開關卩则為翻雙載子 接面電晶體。當第-電阻RD1及第二電阻RD2共同接點A上電壓下降 至設定電壓，使得驅動開關QDET射極端至基極端壓差大於pNp雙載子 ，面電晶體的臨界電壓時’驅動開關卿導通，直流電壓vcc通過限 流電阻RD和聽輸出之檢測信號為高準位電壓，故此高準位電壓的 檢測信號控制放電開關qDIS導通。 圖4A及圖4B為依照本發明另一實施例之未使用功率因數修正器 之具有X電容的交流至直流轉換器之電路圖，圖4A及圖4B所示電路 圖差異僅^於以點線標示的迴路P41和p42不同。請同時參照圖4a 及圖4B ’交流至直流轉換器4包括腿遽波器&、整流滤波器犯以 及放電電路44 ;在本實施例中，腿濾波器41及整流遽波器犯分別 使用如圖2A (或圖2B)所示EMI滤波器21及整流遽波器22之電路， 且直接由整流濾波器42第一端421輸出直流電壓VBUS，其它電路工 =原理在此不再贅述。放電電路44包括第一整流二極體肥、第二整 ^二極體DR2、放電開關⑽s、放電電阻RDIS及檢測電路。第一整流 體刪陽極端輕接至整流遽波器42第三端423，第二整流二極體 陽極端轉接至整_波器42第四端心，第一整流二極體陰 蛋端輕接至第二整流二極體DR2陰極端，放電開關QDls及放電電阻 12 201036312 咖s串熟接並跨接於第一整流二極體聰陰極端（或第二整流二極 體⑽2陰極端）及參考電位GND之間，檢測電路祕至整流遽波器42 第三端423或第四端424以便在檢測到市用交流電AC #移除時輸出檢 測信號控制放電開關QDIS導通。 在本實施例中，檢測電路包括檢測電容cs及檢測驅動器udet， 檢測電容cs轉減膽流驗n 42第三端423及檢_動器隨 之間，而檢測驅動器UDET通過檢測電容Cs來檢測整流濾波器犯第三 端423的電壓是否因市肢流電AC被移除而降低，其中檢測驅動器 UDET的-實施例如圖3所示。在整流滤波器42第三端奶的電· 〇低到某-程度時，檢測驅動器耐判斷市用交流電AC被移除並輸出 檢測信號控制放電開關QDIS導通，此時殘留在χ電容α上的電荷可 通過圖4A所示迴路P41或圖4B所示迴路p42來浪放。當χ電容cx 第:端電位高於第二端電位時’殘留在χ電容α上的電荷通過圖从 所示迴路P41來泡放，此迴路P41由共模電感脱、第二整流二極體 DR2、放電電阻RDIS、呈導通狀態的放電開關QDIS、參考電位⑽、 整流滤波器42第二端422、第二二極體DB2、整_波器42第三端 423及共模電感LF1所形成。當χ電容cx第一端電位低於第二端電位 ◎時’殘留在X電容CX上的電荷通過圖4B所示迴路p 路N2由共模電感LF1、第一整流二極體_、放電電阻 .通狀態的放電開關_、參考電位GND、整流遽波器42第二端422、 第四二極體DB4、整流渡波器42第四端似及共模電感⑽卿成。 同樣地’圖4A (或圖4B)所示放電電阻随的電阻值可以設計遠小於 圖1所示放電電阻RX的電阻值，因此本發明交流至直流轉換器4在市 用交流電AC被移崎可快速地献殘冑在χ電容上 結果可在G. 5秒内使X電容上的賴降為零。 貫 4上所述’本發明交流至直流轉換器在檢_市用交流電被移除 13 201036312 時，才控制放電電阻得以將殘存在x電容上的電荷姐，因此在市用 交流電未被移除時放電電阻不會有功率損耗；再者，本發贩電電阻 的電阻值不需要設雜大’故在市較流電被移除時可快速地泡放殘 留在X電容上的電荷。 雖然本發明已以較佳實施例揭露如上，然其並非用以限定本發 明，任何熟習此技藝者，在不脫離本發明之精神和範圍内，當可作些 許之更動與潤飾’目此本發明之保護細當視後附之巾請專色圍所 界定者為準。 【圖式簡單說明】 圖1為一種現有的交流至直流轉換器之電路圖。 圖2A及圖2B為依照本發明一實施例之使用功率因數修正器之具 有X電容的交流至直流轉換器之電路圖。 圖3為圖2A所示檢測驅動器之電路圖。 圖4A及圖4B為依照本發明另一實施例之未使用功率因數修正器 之具有X電容的交流至直流轉換器之電路圖。 【主要元件符號說明】 I '2、4:交流至直流轉換器 II '21、41 :電磁干擾(EMI)濾波器 RX :放電電阻 cx :安規電容（或X電容） LP1、LF2 :共模電感 12 ' 22、42 :整流濾波器 201036312 221、 421 :整流濾波器第一端 222、 422 :整流濾波器第二端 223、 423 :整流濾波器第三端 224、 424 :整流濾波器第四端 DB1 :第一二極體The Jit electric resistance is connected in series and connected to the first end of the whole_wave device and the second potential of the reference potential; ^I is transmitted to the third end or the fourth end of the rectification ship 11 so as to be moved in the reconciliation city The output detection signal is controlled to control the discharge switch to be turned on. To achieve the above and other objects, the present invention further provides an unusable power factor having an X-capacitance flow to a DC dc, which includes an electromagnetic interference chopper, a rectification filter, and a discharge circuit. Electromagnetic dry (four) 妓, secret to AC ^, electromagnetic dry (four) wave device including Wei capacitor cross-city limb between the fire line and the zero line. The whole filter has the mth, third end and the fourth end, the rectifying chopper is connected to the reference potential, and the third end and the fourth end of the rectifier are respectively connected to the ends of the safety capacitor, and the whole surface wave转换 Convert the city money into money and output it through the first end of the domain filter. The discharge circuit comprises a first-rectifying diode, a second rectifying diode, an electric switch, a discharge resistor and a detecting circuit, a first-rectifying diode anode end to a third end of the rectifying filter, a second rectifying diode The anode end is connected to the fourth end of the rectifying filter, and the first 7 201036312 rectifying diode cathode end is coupled to the second rectifying diode cathode end, and the discharge switch and the discharging resistor are coupled in series and connected to the first rectifying diode Between the body cathode end and the reference potential, the detecting circuit is coupled to the third end or the fourth end of the rectifying filter to output a detection signal to control the discharging of the discharging switch when detecting that the commercial alternating current is removed. The invention can control the discharge resistance to discharge the electric charge remaining on the X electric valley when the detection of the commercial alternating current is removed, so that the discharge resistance does not have power loss when the commercial alternating current is not removed; The resistance value of the discharge resistor of the present invention does not need to be designed to be large, so that the charge remaining on the X capacitor can be quickly discharged when the commercial alternating current is removed. The above and other objects, features and advantages of the present invention will become more <RTIgt; 2A and 2B are circuit diagrams of a parent-to-DC converter having an X-electric valley using a power factor corrector according to an embodiment of the present invention, and the circuit diagram shown in FIG. 2 and FIG. 2β differs only in a point. The lines marked p21 and ρ22 are different. Referring to both the figure and the diagram, the AC to DC converter 2 of the present invention includes an electromagnetic interference (ΕΜΙ) filter 21, a whole filter 22, a power factor corrector (PFC) 23, and a discharge circuit 24. AC to straight "it converter 2 receives the city limb galvanic AC from the public grid, and cascades the fuse FU on the path leading to the live line L or the neutral line N to prevent lightning strikes or large currents from burning internal circuits. The filter 21 is used to suppress electromagnetic noise from the public power grid from being transmitted through the power line, while preventing the electronic device from producing (4) electromagnetic noise transmitted to the power grid through the power line. The EMI filter 21 includes a safety capacitor CX and two common mode inductors Ln and ^2. Each Q is bridged between the live line L and the neutral line N, which is generally referred to as a tantalum capacitor, which is used to cross the fault. The common mode inductors LF1 and LF2 are the same common mode turbulence cutters in the two flux directions. The two sides of the X capacitor cx and the rectifier ferrite 22 are used to filter out the common EMI filter. The wave filter 21 may also include other safety capacitors (not shown in the figure 201036312). For example, an electrostatic capacitor between the ground line L and the ground line or across the neutral line N and the ground, generally referred to as a Y capacitor. It is used to filter out common mode noise. The rectifying filter 22 can use a circuit of the rectifying filter 12 as shown in Fig. 1, having a first end 22, a second end 222, a third end 223, and a fourth end 224. The third end 223 and the fourth end 224 of the rectifying filter and waver 22 are respectively connected to the two ends of the tantalum capacitor cx through the common mode inductors LF1 and (10) to receive the commercial AC AC for filtering electromagnetic noise. The rectifying filter turns the commercial alternating current Ac into a direct current voltage by the second terminal 222 to the reference potential GND' rectifying ferrite 22 and outputs it through the first end 221 of the rectifying filter 22. Lin implemented the 'H-class ϋ 22' including bridge-type rectifying gongs and bristles. The bridge type whole choke is composed of a first diode Pb, a second diode DB2, a third diode and a fourth diode DB4, wherein the first diode is off the anode end. The cathode end is coupled to the fourth end 224 and the first end 221 of the rectifying filter 22, and the anode end and the cathode end of the second diode DB2 are coupled to the second end 222 and the third end 223 of the rectifying filter 22, respectively. The anode end and the cathode end of the third body DB3 are respectively coupled to the third end of the rectifying filter 22, the second end, the second end, the second end, and the fourth end of the fourth body, DB4, and the cathode end are respectively connected to the rectifying and extinguishing device 22, respectively. End 222 and fourth end 224. In another embodiment, the bridge rectifier can be composed of a transformer with a middle tap on the secondary side and two diodes, and the two ends of the transformer are the third end 223 and the fourth end 224 of the rectifying filter 22, two The anode ends of the diodes are respectively secreted to the two ends of the secondary side of the transformer, and the cathode ends of the two diodes are connected to the first end 221 of the rectifier filter 22, and the intermediate tap of the secondary side of the transformer is coupled to the rectifier filter 22 Two ends four. In this embodiment, the filter is composed of a filter capacitor CB. The filter capacitor (3) is connected across the first end 221 and the second end 222 of the rectifier waver 22 to reduce the first end of the rectifier filter 22. The chopping of the output voltage causes the first end 221 of the rectifying filter 22 to output a relatively stable DC voltage. In another embodiment, the filter may be an inductor-capacitor filter (such as an LC filter) or a π-type filter (such as a CLC filter). However, the use of a bridge rectifier in the 'rectifier waver 22 causes the current distortion of the commercial AC AC wheel into the 201036312 rectifier filter 22. Generally, the current waveform of the AC input of the commercial AC is adjusted by adding pfc to the rear end of the rectifier filter 22. In order to improve current distortion, especially for electronic devices with power above 75W, it is necessary to add ρπ to meet the specification of spectral current. Pp>c 23 is coupled to the first end 221 of the rectifying filter 22 and the reference potential GND, and outputs a DC voltage VBUS ' at a high voltage level to provide a DC-to-DC converter to convert the DC voltage VBUS of the high voltage level into different A low voltage level DC voltage to provide an electrical power source for operating the electronic device. In this embodiment, the PFC 23 can use the circuit of the pFC 13 shown in FIG. i, which adopts an active step-up type (b〇ost) DC-to-DC converter, so the pFC 23 includes a PFC driver UPFC, a power switch QPFC, Inductor LPFC, diode 〇pFC and capacitor CPFC. The PFC driver UPFC returns the control power switch QPFC according to the DC voltage VBUS outputted by the PFC 23, and when the power switch QPFC is turned on (〇N), the input energy is stored in the inductor LPFC and the energy stored in the electric valley CPFC is supplied to the output; When the power switch qpfc is turned off _), the input power and the energy stored in the inductor LpFC are supplied to the output, so that the DC voltage VBUS of a typical value of 380 to 400 V is output during operation 23 . The discharge circuit 24 includes a discharge switch QDIS, a discharge resistor RDIS, and a detection circuit. The old electric switch QDIS and the discharge resistor RDIS are connected in series and connected between the rectifying filter and the first green 221 and the reference potential GND, and the detecting circuit is reduced to the rectifying filter 22, the three end anger or the fourth end 224 for detecting When the AC power is removed from the city, the output discharge switch _ is turned on. In this implementation, the detection of the f-packet detection drive country T. Checking (10) with a shirt-viewing second end, detection = connected to the third end 223 of the rectifying filter 22; in other words, the detecting capacitor is connected to the third end 223 of the rectifying device 22 and detecting the drive ΕΤ ^ the chopper 22 The third end 223 = decreased due to the removal of the city parent current AC. When the rectifier NDET determines that the power supply of the three-terminal 223 of the commercial alternating current is reduced to a certain extent, the detection drive AC is removed and the detection signal is output to control the discharge switch 卯κ 201036312 V-pass 'one residual at x at this time The charge on the capacitor cx can be discharged through the circuit p2i shown in Fig. 2 or the path P22. The two ends of the X capacitor cx are defined as a first end and a second end, respectively, and the end is connected to the neutral line N and the second end is switched to the live line L. When the first terminal potential of the X capacitor cx is souther than the potential of the second terminal, the charge remaining on the X capacitor CX is discharged through the loop P21j shown in FIG. 2A. The loop P21 is composed of the common mode inductor LF2 and the fourth end of the rectifier filter. 4, the a-th body (10), the first end 221 of the rectifying filter 22, the discharge resistor RDIS, the discharge switch QDIS in the on state, the reference potential gnd, the rectification filter, the second end 222 of the waver 22, the first one body The DB2, the third end 223 of the rectifying chopper 22 and the common mode inductor LF1 are formed, and the discharge resistor RDIS in the circuit f consumes the electric charge remaining on the tantalum capacitor α. When the fourth potential of the X electric valley CX is lower than the potential of the second end, the charge remaining on the X capacitor is turned on, and the circuit P22 shown in FIG. 2B is turned on. The circuit p22 is composed of the common mode inductor Ln and the rectifying chopper 22 The first end of the three-terminal 223, the third diode Cong, the rectifier chopper 22, such as ^, the electric resistance RDIS, the discharge switch s in the _ state, the reference potential (10), the second end 222 of the rectifying chopper 22, The fourth diode DB4 and the fourth end of the rectifier filter 22 are formed by the inductor LF2. When the AC switch is not removed, the discharge switch is disconnected and the circuits P21 and P22 are disconnected, so the discharge resistor _ will not have power secret; only the side AC to the commercial AC AC is removed. When the discharge switch _ is turned on to make the above-mentioned loops p2i and P22 pass, the discharge resistor _ can consume the charge remaining on the tantalum capacitor cx; because this (four) AC to straight_shop 2 can meet the standby conversion loss Requirements, such as standby power loss must be less than 15〇mW. In addition, since the discharge resistance is not connected in parallel to the X capacitor cx, it is not necessary to design the resistance value of the discharge resistor to be large; in other words, the resistance value of the discharge resistor RDIS shown by ffl 2A (or ® 2B) Yes: The design is much smaller than the resistance value of the discharge resistor RX shown in Fig. 1. Therefore, the AC to the direct current device 2 can quickly touch the residual force on the 肢f capacity when the urban limb galvanic AC is removed, according to The result of the test can reduce the voltage on the X capacitor to zero within 0.5 seconds. 201036312 * r Figure 3 is a circuit diagram of the detection driver UDET shown in Figure 2A (or Figure 2B). Referring to FIG. 3', the detection driver UDET includes a rectifier diode dd, a first resistor RD1, a second resistor Rj), a chopper grid CD, and a drive switch QDET. The anode end of the rectifying diode DD is lightly connected to the second end of the detecting capacitor CS, and the first resistor rdi and the second resistor RD2 are coupled in series and connected between the cathode terminal of the rectifying diode DD and the reference potential GND. The filter capacitor (3) is connected across the first resistor RD1 and the first resistor RD2 between the common contact A and the reference potential GND. The driving switch qdet outputs a detection signal in response to the voltage drop of the first resistor RD1 and the second resistor rib 2 at the common contact A to the set voltage to control the discharge switch qDIS to be turned on. In this embodiment, the drive switch QDET is a PNP bipolar junction junction transistor, and the discharge switch 卩 is a flip bipolar junction junction transistor. When the voltage of the first resistor RD1 and the second resistor RD2 at the common contact A drops to a set voltage, so that the voltage difference between the driving terminal QDET and the base terminal is greater than the pNp double carrier, the threshold voltage of the surface transistor is 'driving the switch'. The DC voltage vcc passes through the current limiting resistor RD and the detection signal of the hearing output is a high level voltage, so the detection signal of the high level voltage controls the discharge switch qDIS to be turned on. 4A and FIG. 4B are circuit diagrams of an AC to DC converter having an X capacitor without a power factor corrector according to another embodiment of the present invention, and the circuit diagrams shown in FIGS. 4A and 4B are only indicated by dotted lines. Circuits P41 and p42 are different. Please refer to FIG. 4a and FIG. 4B simultaneously. 'AC to DC converter 4 includes leg chopper & rectifier filter and discharge circuit 44. In this embodiment, leg filter 41 and rectifier chopper are used separately. As shown in FIG. 2A (or FIG. 2B), the circuit of the EMI filter 21 and the rectifying chopper 22 is directly outputted from the first end 421 of the rectifying filter 42 to the DC voltage VBUS. Other circuit operators=the principle is not described herein again. The discharge circuit 44 includes a first rectifying diode fertilizer, a second integral diode DR2, a discharge switch (10) s, a discharge resistor RDIS, and a detection circuit. The anode of the first rectifier is lightly connected to the third end 423 of the rectifier chopper 42 , and the anode end of the second rectifier diode is switched to the fourth end of the entire wave 42 , and the first rectifier diode is closed. Lightly connected to the cathode end of the second rectifying diode DR2, the discharge switch QDls and the discharge resistor 12 201036312 are spliced and connected across the first rectifying diode Cong cathode end (or the second rectifying diode (10) 2 cathode end And between the reference potential GND, the detection circuit is secreted to the third end 423 or the fourth end 424 of the rectifying chopper 42 to output a detection signal to control the discharge switch QDIS to be turned on when the commercial AC AC ## is removed. In this embodiment, the detecting circuit includes a detecting capacitor cs and a detecting driver udet, and the detecting capacitor cs is reduced between the third end 423 of the biliary flow test n 42 and the detecting device, and the detecting driver UDET is detected by detecting the capacitor Cs. The rectifier filter determines whether the voltage at the third terminal 423 is reduced due to the removal of the city limb galvanic AC, wherein the implementation of the sense driver UDET is as shown in FIG. When the electric power of the third end of the rectifying filter 42 is low to a certain degree, the detecting driver is judged to be resistant to the determination that the commercial AC AC is removed and the detection signal is output to control the discharge switch QDIS to be turned on, at which time the residual capacitance is on the tantalum capacitor α. The charge can be discharged by the circuit P41 shown in Fig. 4A or the circuit p42 shown in Fig. 4B. When the potential of the tantalum capacitor cx is higher than the potential of the second terminal, the charge remaining on the tantalum capacitor α is bubbled through the circuit P41 shown in the figure. This circuit P41 is removed by the common mode inductor and the second rectifier diode is removed. DR2, discharge resistor RDIS, discharge switch QDIS in conduction state, reference potential (10), second end 422 of rectifier filter 42, second diode DB2, third end 423 of integer waver 42 and common mode inductor LF1 . When the potential of the first terminal of the tantalum capacitor cx is lower than the potential of the second terminal ◎, the charge remaining on the X capacitor CX passes through the circuit p of N2 shown in FIG. 4B from the common mode inductor LF1, the first rectifying diode _, and the discharge resistor. The discharge switch of the on state, the reference potential GND, the second end 422 of the rectifying chopper 42, the fourth diode DB4, the fourth end of the rectification waver 42 and the common mode inductance (10). Similarly, the resistance value of the discharge resistor shown in FIG. 4A (or FIG. 4B) can be designed to be much smaller than the resistance value of the discharge resistor RX shown in FIG. 1, so that the AC to DC converter 4 of the present invention is moved to the AC in the commercial AC. The result of quickly disposing of the enthalpy on the tantalum capacitor can reduce the dependence on the X capacitor to zero within G. 5 seconds. According to the above description, the AC to DC converter of the present invention is inspected when the commercial AC power is removed 13 201036312, and then the discharge resistor is controlled to be stored on the x capacitor, so the commercial AC is not removed. When the discharge resistor does not have power loss; in addition, the resistance value of the power-selling resistor does not need to be mixed, so that the charge remaining on the X capacitor can be quickly bubbled when the city is removed from the current. Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the invention, and those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The protection of the invention shall be subject to the definition of the attached towel. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a circuit diagram of a conventional AC to DC converter. 2A and 2B are circuit diagrams of an AC to DC converter having an X capacitor using a power factor corrector in accordance with an embodiment of the present invention. Figure 3 is a circuit diagram of the test driver shown in Figure 2A. 4A and 4B are circuit diagrams of an AC to DC converter having an X capacitor without a power factor corrector according to another embodiment of the present invention. [Main component symbol description] I '2, 4: AC to DC converter II '21, 41: Electromagnetic interference (EMI) filter RX: Discharge resistor cx: Safety capacitor (or X capacitor) LP1, LF2: Common mode inductor 12 ' 22, 42 : Rectifier filter 201036312 221, 421 : Rectifier filter first end 222, 422 : Rectifier filter second end 223, 423 : Rectifier filter third end 224, 424 : Rectifier filter fourth end DB1: first diode
DB2 :第二二極體 DB3 :第三二極體 DB4 :第四二極體 CB :濾波電容 13、23:功率因數修正器（PFC) UPFC : PFC驅動器 QPFC :功率開關 LPFC :電感 DPFC :二極體 CPFC :電容 24、44 :放電電路 CS :檢測電容 UDET :檢測驅動器 DD :整流二極體 RD1 :第一電阻 15 201036312 RD2 :第二電阻 A:共同接點 CD :濾波電容 QDET :驅動開關 RD、RDIS :限流電阻 DR1 :第一整流二極體 DR2 :第二整流二極體 η VCC :直流電壓 QDIS :放電開關 RDIS :放電電阻 AC:市用交流電 L :火線 Ν :零線 GND :參考電位 Ο VBUS :直流電壓 FU :保險絲 PI、Ρ21、Ρ22、Ρ4卜 Ρ42 :迴路 16DB2: second diode DB3: third diode DB4: fourth diode CB: filter capacitor 13, 23: power factor corrector (PFC) UPFC: PFC driver QPFC: power switch LPFC: inductor DPFC: two Polar body CPFC: capacitor 24, 44: discharge circuit CS: detection capacitor UDET: detection driver DD: rectifier diode RD1: first resistor 15 201036312 RD2: second resistor A: common contact CD: filter capacitor QDET: drive switch RD, RDIS: Current limiting resistor DR1: First rectifying diode DR2: Second rectifying diode η VCC: DC voltage QDIS: Discharge switch RDIS: Discharge resistor AC: Municipal AC L: Fire Ν: Zero line GND: Reference potential Ο VBUS : DC voltage FU : Fuse PI, Ρ 21, Ρ 22, Ρ 4 Ρ 42 : Circuit 16