201240293 六、發明說明： 【發明所屬之技術領域】 本發明係有關於—種脈波寬度㈣之電源 J置，特別是指一種於變壓器之二次側以同步整 流開關電路進行脈波寬度調變之脈波寬度調變 之同步整流電源裝置。 【先前技術】 請參閱第i圖所示，其係為習知中華民國專 ^公報證書第〇35874號「高效率推挽式電源電 」之電路示意圖，該脈波寬度調變晶片8 2設 於隔離驅動變壓器84之低壓側842，且該切= 開關電路85設於隔離驅動變壓器84之高壓側 841與變壓器81之高壓側811 @，又該調幅脈 波放大電路83設於隔離驅動變壓器84之低壓側 842與脈波寬度調變晶片82間，另該變壓器 之低壓側81 2設有輸出整流電路8 6。藉由該切 換開關電路85之開關元件qi、⑽為場效電晶體 (M0SFET)，且利用場效電晶體低消耗功率之特 性，而可降低開關元件Q1、Q2之切換損失，並 同時將脈波寬度調變晶片82設置於隔離驅動變 壓器84之低壓側842，而可使得該脈波寬度調 變as片8 2於低壓段工作，因而可避免高壓側其 高電壓雜訊影響之目的。 該「高效率推挽式電源電路」其脈波寬度 201240293 "周變sa片82雖可避免高壓側其高電壓雜訊影響 之目的，惟當該外部負載由重載降至輕載、或空 載寺往往因該「南效率推挽式電源電路」並未 設有任何變頻電路或裝置，而使該「高效率推挽 式電源電路」在任何負载下，該脈波寬度調變晶 片82其控制訊號之切換頻率固定不變，因而造 成該切換開關電路85其開關元件Q1、Q2之切換 ，失無法下降，因此常造成使用上的不便。且該 變i器81之低壓側81 2所連接之整流電路8 6係 設=為二極體，不僅在製程與材料成本相對花費 二同’且整流效率差造成溫度偏高’更無法與高 壓側811之該切換開關電路85達成同步整流之 功效’相對使得該變壓器81成本不易降低，因 =何去降低成本’—直是業者所急迫有待尋求 解決之方案以及改進之處。 【發明内容】 本發明之目的係在提供一種脈波寬度調變 之同步整流電源裝置’其係藉由隔離電路驅動變 壓：開關元件外’刊樣驅動變頻脈波訊 同步整流之金氧半場效電晶冑，將改善驅動時序 問相及改善一般同步整流相位損失，並可降低 整流切換損失’進而達到提高節能之功效。降低 本發明之目的係在提供-種脈波寬度調變 之同步整流電源裝置，其係藉由輸出-組以上^ 4 201240293 動訊號’除可經隔離元件驅動一次側開 動1以上：：：其同步的變頻脈波驅動訊號驅 - 欠側所*位置於一次側的同步整流電路，以二 斤連接之同步整流開關電路設計為且有 彻電晶體，將取代傳統上= 電路達到降低製程與材料花 整流效率降低溫度之功效。 乂及緹冋 :發明之目的係在提供一種脈波寬度調變之 :/正流電源裝置’其係可藉由負載的輕載、重 載比例調整該變頻電路其振盪訊號之頻率，而可 使該脈波寬度調變控制電路其脈波訊號達到變 頻之功效。 為達上述之目的，本發明之脈波寬度調變之 同步整流電源裝置，係包括：—變壓_、—脈波 寬度調變控制電路、一同步整流開關電路以及二 變頻電路。該變壓器具有一次側與二次側，且以 一隔離電路隔離一次側與二次側，而一次側以— 切換開關電路提供驅動該變壓器，二次側以一黄 波電路輸出各種電壓至外部負载。該脈波寬度= 變控制電路位於二次側上，並連接該隔離電路^ 及該濾波電路，該脈波寬度調變控制電路產生一 控制信號至該隔離電路，以驅動該切換開關電 路。該同步整流開關電路位於二次側上，並連接 該脈波寬度調變控制電路，該同步整流開關電路 201240293 接收該脈波寬度言周變控制電路所提供之一延遲 時序控制信號。 :本發明較佳實施例中，該脈波寬度調變之 電源裝置更包括有-變頻電路，該變頻 古〜糸位於該—次側上，該變頻電路連接該脈 波見度調變控制電路以及該滤波電路，該變頻電 路以該外部負載之變化，使該脈波寬度調變控制 J路之脈波訊號變頻。於本發明另一較佳實施例 中，該變頻電路連接該脈波寬度調變控制電路以 及該隔離電路，該變頻電路以該隔離電路取得該 切換開關電路負載之變化，使該脈波寬 制電路之脈波訊號變頻。 本發明之其他特點及具體實施例可於以下配 合附圖之詳細說明中，進一步瞭解。 【實施方式】 請參閱第2A圖至第2B圖所示，其係 明脈波寬度調變之同步整流電源裝置第二： 實施例電路及方塊示意圖。本發明脈波寬度 之同步整流電源裝置，係包括：一變壓器卜— =寬度調變控制電路4以及一同步整；； 路6。該變壓器1具有-次側U與二次側乂電 該變屋器1為-半橋式變壓器、一全橋式變壓 ，挽式變壓器、一換流變麗器、—馳返 變壓器以及一前向式變壓器其中之一。該變壓； 201240293 1以一隔離電路3隔離一次側1 1與二次側1 2， 而一次侧11以一切換開關電路5提供驅動該變 璧器1，該切換開關電路5設有至少一組切換開 關’為便於說明書進行，本發明較佳實施例中， 該切換開關為金氧半場效電晶體s丨、S2，當然該 切換開關也可為絕緣栅雙極電晶體（Insulated201240293 VI. Description of the Invention: [Technical Field] The present invention relates to a power supply J for a pulse width (four), and particularly to a pulse width modulation of a synchronous rectification switching circuit on a secondary side of a transformer A synchronous rectification power supply device with a pulse width modulation. [Prior Art] Please refer to the figure in the figure i, which is a circuit diagram of the "High-efficiency push-pull power supply" of the Republic of China, No. 35874, the pulse width modulation chip 8 2 The low voltage side 842 of the drive transformer 84 is isolated, and the cut = switch circuit 85 is disposed on the high voltage side 841 of the isolation drive transformer 84 and the high voltage side 811 @ of the transformer 81, and the amplitude modulation pulse amplification circuit 83 is disposed on the isolation drive transformer 84. The low voltage side 842 is interposed between the pulse width modulation chip 82, and the low voltage side 81 2 of the transformer is provided with an output rectifying circuit 86. The switching elements qi and (10) of the switching circuit 85 are field effect transistors (MOSFETs), and the switching power loss of the switching elements Q1 and Q2 can be reduced by utilizing the characteristics of low power consumption of the field effect transistors. The wave width modulation chip 82 is disposed on the low voltage side 842 of the isolation drive transformer 84, so that the pulse width modulation as piece 8 2 operates in the low voltage section, thereby avoiding the purpose of high voltage noise on the high voltage side. The "high-efficiency push-pull power supply circuit" has a pulse width of 201240293 "the variable-variation sa piece 82 can avoid the influence of high-voltage noise on the high-voltage side, but when the external load is reduced from heavy load to light load, or The no-load temple often has no "frequency-adjusting power supply circuit" and does not have any frequency conversion circuit or device, so that the "high-efficiency push-pull power supply circuit" is under any load, the pulse width modulation chip 82 The switching frequency of the control signal is fixed, thereby causing the switching switch circuit 85 to switch between the switching elements Q1 and Q2, and the loss cannot be lowered, so that the inconvenience in use is often caused. And the rectifier circuit 86 connected to the low-voltage side 81 2 of the variable device 81 is set to be a diode, which not only has a relatively low cost in terms of process and material cost, but also has a high temperature due to poor rectification efficiency. The switching switch circuit 85 of the side 811 achieves the effect of synchronous rectification 'relatively making the cost of the transformer 81 less difficult to reduce, because of the cost reduction', which is an urgent solution and improvement of the industry. SUMMARY OF THE INVENTION The object of the present invention is to provide a synchronous rectification power supply device with pulse width modulation, which is driven by an isolation circuit to transform a voltage: a switching element outside the 'sample-driven variable frequency pulse wave synchronous rectification of the golden oxygen half field The utility model will improve the driving timing and improve the phase loss of the general synchronous rectification, and can reduce the switching loss of the rectification, thereby improving the energy saving effect. The purpose of reducing the purpose of the present invention is to provide a synchronous rectification power supply device with a pulse width modulation, which is driven by an output-group above 4 201240293 motion signal ', except that the primary side can be driven by the isolation element to drive more than 1::: Synchronous variable frequency pulse wave drive signal drive - the underside side is located on the primary side of the synchronous rectification circuit, with a two-pound connection of the synchronous rectification switch circuit designed and has a transistor, which will replace the traditional = circuit to reduce the process and materials Flower rectification efficiency reduces the effect of temperature.乂 and 缇冋: The purpose of the invention is to provide a pulse width modulation: / positive current power supply device's which can adjust the frequency of the oscillation signal of the frequency conversion circuit by the light load and heavy load ratio of the load. The pulse width modulation control circuit realizes the function of the pulse wave signal to achieve frequency conversion. In order to achieve the above object, the pulse-wave width modulation synchronous rectification power supply device of the present invention comprises: a transformer _, a pulse width modulation control circuit, a synchronous rectification switch circuit and a second frequency conversion circuit. The transformer has a primary side and a secondary side, and isolates the primary side and the secondary side by an isolation circuit, and the primary side drives the transformer with a switching circuit, and the secondary side outputs various voltages to an external load with a yellow wave circuit. . The pulse width = variable control circuit is located on the secondary side and is coupled to the isolation circuit and the filter circuit. The pulse width modulation control circuit generates a control signal to the isolation circuit to drive the switch circuit. The synchronous rectification switch circuit is located on the secondary side and is connected to the pulse width modulation control circuit. The synchronous rectification switch circuit 201240293 receives one of the delayed timing control signals provided by the pulse width variable control circuit. In a preferred embodiment of the present invention, the pulse width modulation power supply device further includes a frequency conversion circuit, wherein the frequency conversion is located on the secondary side, and the frequency conversion circuit is connected to the pulse wave modulation control circuit. And the filter circuit, wherein the frequency conversion circuit converts the pulse wave signal of the J-path by the pulse width modulation control by the change of the external load. In another preferred embodiment of the present invention, the frequency conversion circuit is connected to the pulse width modulation control circuit and the isolation circuit, and the frequency conversion circuit obtains the change of the load of the switch circuit by the isolation circuit, so that the pulse width is Pulse signal conversion of the circuit. Other features and embodiments of the invention will be apparent from the following detailed description of the drawings. [Embodiment] Please refer to FIGS. 2A to 2B, which illustrate a second embodiment of a synchronous rectification power supply device with pulse width modulation: an embodiment circuit and a block diagram. The synchronous rectification power supply device of the pulse width of the present invention comprises: a transformer b = a width modulation control circuit 4 and a synchronous whole; The transformer 1 has a secondary side U and a secondary side. The transformer 1 is a half bridge transformer, a full bridge transformer, a pull transformer, a commutation converter, a flyback transformer, and a One of the forward-type transformers. The transformer 1 is isolated from the primary side 1 1 and the secondary side 1 2 by an isolation circuit 3, and the primary side 11 is driven to drive the converter 1 by a switching circuit 5, the switching circuit 5 is provided with at least one In the preferred embodiment of the present invention, the switch is a gold-oxygen half-field effect transistor s丨, S2. Of course, the switch can also be an insulated gate bipolar transistor (Insulated).
Gate Bipolar Transistor，IGBT)，或是雙載子 接面電晶體（Bip〇iar· Junction Transistor， BJT)。而該二次側12以一濾波電路7輸出各種 電壓至外部負載。 於本發明較佳實施 同步整流電源裝置更包括有一變頻電路2，該變 頻電路2其係位於該二次側丨2上，該變頻電路2 連接該脈波寬度調變控制電路4以及該濾波電路 而該變頻電路2中之内部電壓（VRE)為可調整 °又疋負載狀況變頻位準，亦可設定為負載多寡 時，開始變頻範圍為100%〜0%，當設定為1〇〇%時， 即可全段變頻，或當設定為〇%時即可全段不變 頻，亦即不需要該變頻電路2。而該變頻電路2 以該外部負載之變化，使該脈波寬度調變控制電 路4之脈波訊號變頻。當然，該變頻電路2亦可 =接該脈波寬度調變控制電路4以及該隔離電 •該變頻電路2以該隔離電％ 3取得該切換 幵L電路5負載之變化，使該脈波寬度調變控制 201240293 電路4之脈波訊號變頻。 該脈波寬度調變控制電路4位於二次側j 2 上，並連接該隔離電路3以及該濾波電路7,該 脈波寬度調變控制電路4產生一控制信號至該隔 離電路3，以驅動該切換開關電路5。該同步整 流開關電4 6位於二次側12上，並連接該脈波 寬度調變控制電路4，當然該脈波寬度調變控制 電路4可以僅連接單—同步整流開關電路6以及 濾波電路7，於本發明較佳實施例中，該脈波寬 度調變控制電路4係同時連接二組同步整流開關 電路6、6a以及濾'波電路7、7a，諸如此類數量 之變化乃熟悉此項技藝者所能依據上述之說明 加以變化實施，故並不脫離本發明之要義所在， 亦不脫離本發明之精神及範圍，於此並不再多加 琢问芡整流開關電路Gate Bipolar Transistor (IGBT), or bipolar junction transistor (BJ〇iar·Junction Transistor, BJT). The secondary side 12 outputs various voltages to an external load by a filter circuit 7. Preferably, the synchronous rectification power supply device further includes a frequency conversion circuit 2, which is located on the secondary side 丨2, and the frequency conversion circuit 2 is connected to the pulse width modulation control circuit 4 and the filter circuit. The internal voltage (VRE) in the frequency conversion circuit 2 is adjustable ° and the load state frequency conversion level, and can also be set to the load amount, the frequency conversion range is 100%~0%, when set to 1〇〇% , the whole frequency conversion can be performed, or when the setting is 〇%, the whole section can be not converted, that is, the frequency conversion circuit 2 is not needed. The frequency conversion circuit 2 converts the pulse wave signal of the pulse width modulation control circuit 4 by the change of the external load. Of course, the frequency conversion circuit 2 can also be connected to the pulse width modulation control circuit 4 and the isolation power supply circuit 2 to obtain the change of the load of the switching circuit 5 by the isolation power %3, so that the pulse width is Modulation control 201240293 Circuit 4 pulse signal conversion. The pulse width modulation control circuit 4 is located on the secondary side j 2 and is connected to the isolation circuit 3 and the filter circuit 7. The pulse width modulation control circuit 4 generates a control signal to the isolation circuit 3 to drive The switch circuit 5 is switched. The synchronous rectification switch power 46 is located on the secondary side 12 and is connected to the pulse width modulation control circuit 4. Of course, the pulse width modulation control circuit 4 can be connected only to the single-synchronous rectification switch circuit 6 and the filter circuit 7. In the preferred embodiment of the present invention, the pulse width modulation control circuit 4 is connected to the two sets of synchronous rectification switch circuits 6, 6a and the filter 'wave circuits 7, 7a at the same time, and the like is known to those skilled in the art. It can be implemented in accordance with the above description, and does not depart from the spirit of the present invention, and does not deviate from the spirit and scope of the present invention.
胃 / ^ J 場效電晶體SRI、SR2。請加參閱第3圖所示之 發明切換開關電路與同步整流開關電路之時^ 控制示意圖，即當該金氧半場效電晶冑W作售 時，該金氧半場效電晶體S2係為不作動，且 及S2交互作動間會有一 DEAD TIME七，，以 該切換開關電路5短路。而該同步整流: 6接收該脈波寬度調變控制電路4所摇 遲時序t”在調整…脈波訊號經匕: 8 201240293 3到變壓器1能量轉換過程中與同步整流驅動脈 波訊號的時間差，可以使得該同步整流開關電路 6、6a之該金氧半場效電晶體SR1、SRia與該切 換開關電路5之該金氧半場效電晶體S1為同步 作動，且該同步整流開關電路6 效電晶體SR2、SR2a盥竽切拖戸"弓中 琢 KZa興忒切換開關電路5之該金 氧半場效電晶體S2為同步作動亦可隨該變壓器i ，繞法而互換，如此不僅可以將本發明之該變壓 器以該變頻電路2進行脈波寬度調變，更可藉 由°亥同步整流開關電路6使該變壓器1達到驅動 一組以上同步整流之功效。 以下因大部份的元件係相同或類似於 =，因此相同之元件將直接給予相同之名稱Stomach / ^ J field effect transistor SRI, SR2. Please refer to the control diagram of the invention switching switch circuit and the synchronous rectification switch circuit shown in FIG. 3, that is, when the gold-oxygen half field effect transistor W is sold, the gold-oxygen half field effect transistor S2 is not Actuation, and there will be a DEAD TIME seven between the S2 interaction, short circuit with the switch circuit 5. And the synchronous rectification: 6 receives the pulse width modulation control circuit 4, the delay timing t" is adjusted... the pulse signal is 匕: 8 201240293 3 to the transformer 1 energy conversion process and the synchronous rectification driving pulse signal time difference The MOS field SR1, SRia of the synchronous rectification switch circuit 6, 6a and the MOS field S1 of the switch circuit 5 can be synchronized, and the synchronous rectification circuit 6 is powered. The crystals SR2, SR2a are cut and dragged, and the gold-oxygen half-effect transistor S2 of the KZa Xing switch circuit 5 is synchronously operated and can be interchanged with the transformer i and the winding method. In the transformer of the invention, the pulse width modulation is performed by the frequency conversion circuit 2, and the transformer 1 can be driven to drive more than one group of synchronous rectification by the synchronous synchronization switching circuit 6. The following is because most of the components are the same. Or similar to =, so the same component will be given the same name directly
:至扁：’且不予贊述，合先敘明。請參閱第4A 夕J 4C圖所示’其係為本發明脈波寬度調變 之同步整流電源裝置第二較 電路之動作m # 變頻 土国 乍 及振盪訊號與脈波訊號之變頻示 ㈣電路2内設有一檢知電路21 一比 工1電路22以及_振盪電路23，該檢知 之一為：電壓檢知電路以及-電流檢知電路其中 < ’戎比例控制雷政9 9 i山* 路21，該振盪電路23 一二接於該檢知電 路22，且另一端 '表姑 舳連接於該比例控制電 4。 連接於該脈波寬度調變控制電路 201240293 該變實施例該遽波電路7與 24,該取樣電路24人：，<間設有-取樣電路 控制電路4,連接於該脈波寬度調變 狀況傳送至變頻樣電路，所測得之負載 配合參閱第4Β圖内：：:。電路2卜請再 其輸入端之負载迴可㈣檢知電路21 、戟沿技電壓VFB可取馄 況之電壓參考值，者 Τ取侍負載狀 取得切換開關電路Γ;載：由經：隔離電路3 降時，可使該負載迴^「因此當負載下 當負載上升時壓”β下降；反之， 升。而當該負载迴I電壓負下=VFB上 檢知電路21其内部電 ：：，稭由該 壓"B相比較，且一 了與負载迴授電 電壓V ref $、σ 、凡件211可使該内部: To the flat: 'And not to mention, first to explain. Please refer to Figure 4A, J 4C, which is the second circuit of the synchronous rectification power supply unit with the pulse width modulation of the present invention. m # Frequency conversion country and the frequency conversion signal of the oscillation signal and the pulse signal (4) circuit 2 is provided with a detection circuit 21, a ratio 1 circuit 22 and an oscillating circuit 23. One of the detections is: a voltage detection circuit and a current detection circuit, wherein < '戎 proportional control Lei Zheng 9 9 i mountain* In the circuit 21, the oscillating circuit 23 is connected to the detecting circuit 22, and the other end is connected to the proportional control circuit 4. Connected to the pulse width modulation control circuit 201240293. In the modified embodiment, the chopper circuits 7 and 24 are provided with a sampling circuit control circuit 4 connected to the pulse width modulation. The condition is transmitted to the variable frequency sample circuit, and the measured load is referred to in Figure 4:::. Circuit 2, please load the input end of the circuit (4) detection circuit 21, the edge voltage VFB can take the voltage reference value of the state, take the load to obtain the switch circuit Γ; load: by: isolation circuit 3 When the time is lowered, the load can be returned to "so when the load rises, the pressure "β drops"; otherwise, rises. When the load returns to the I voltage negative = VFB, the internal circuit of the detection circuit 21 is::, the straw is compared by the pressure " B, and the load feedback voltage V ref $, σ, 211 Can make the interior
轉換為輸出端㈣VFB比較之結果 π询£ϋ Μ之負載電流I FB與負載迴授電壓ν ρβ 、载電流 载下降時，而可使該 成反比。因此當負 載迴授電>1 v FB 路21其輸入端之負 21其輸出端之負載電而可使該檢知電路 杏 貝戰电机I FB上升。 δ該檢知電路21其輸出 上升時，藉由該比例控制電二：負？電流IFB 檢知電路…且該振盈電:二：端連接於該 例控制電路22。兮产 鸲連接於該比 Μ知電路2!其輪出端之負載 201240293 電流I FB流入該比例控制電路22其金氧半場 效電晶體Q FB ’而可使該金氧半場效電晶體q F B導通、且同時該惺電流I t產生分流，而可 使§玄分電流I A流入金氧半場效電晶體q a ， 因而可使該金氧半場效電晶體q A呈導通狀 態’進而可使該振盪電路23之充電電流I c變 小’即該負載電流I FB上升而可控制該振盪電 路23其充電電流I C變小下降。因此當該充電 電流ic變小下降時，可使該振盪電路23其電 容C緩慢充電，而可使該電容c之電壓v c緩 k上升，且使該電容C之充電時間t丨增加，俾 當該電容c之電壓vc充電到與内部電壓νι 相等時，藉由該電容C之電壓v c可對該金氧 半場效電晶體QB進行放f，而可使該振盈電 路23產生振盪訊號24，且可使該週期時間η 增加’同時再藉由該週期時@ η肖頻率成反 比，而可使該振盪訊E 24其頻率下降，進 達到降低該振盪訊號24其頻率之目的。 丹错由該脈波寬度調變控制電路4 一 而可使該脈波寬度調變= 電路4接收該振_ 23所產生之振盪訊號 使該：t當该振盪訊號24之頻率降低時，俾； 導LG:度調變控制電路4其脈波訊號26之 導通時間n 0N與非導通時間n _、及週 201240293 期總時間T1 total增加，而可使該脈波週期 (duty CyCie)增加’且可使該脈波訊號26其頻 率下降’因而可達到降低該脈波訊號2 6其頻 率，進而可使該脈波寬度調變控制電路4其脈 波訊號26達到變頻之目的。 該隔離電路3 —端連接於該脈波寬度調變 控制電路4,且該隔離電路3設有一隔離元件 32 ’以隔離一次側11與二次側1 2，而隔離元件 32要驅動該切換開關電路5，必須將一低電壓 轉成尚電壓之後才能驅動，所以於該脈波寬度 調變控制電路4上加裝一圖騰埠放大電路4〇， 該圖騰埠放大電路40能讓隔離元件32的輸出 瞬間電流提供驅動該切換開關電路5輸入電容 (ClSS)所需，這樣一來要驅動該切換開關電路5 也較容易，最後將該圖騰埠放大電路4〇連接該 脈波寬度调變控制電路4，並使該脈波寬度調變 控制電路4用來產生一控制信號，該控制信號 經由圖騰埠放大電路4〇放大後，讓該隔離電路 3接收以驅動該切換開關電路5。當然，該脈波 寬度調變控制電路4具有一延遲時序控制電路 ^該延遲時序控制電路41提供該延遲時序控 制f。號至該同步整流開關電4 6，，亦可將該延遲 夺f控制“號經由圖騰埠放大電路4 0放大後， 提供至該同步整流開關電路6。該隔離元件 201240293 32可為隔離變壓器，又該隔離元件”也可為光 耦合器，另該隔離元件32也可為磁性元件。因 此，本發明可依負载的輕載、重载比例調整該 脈波寬度調變晶片10其振蘯訊號24之頻率， 而可使該脈波寬度調變控制電路4其脈波訊號 26達到變頻之功效’進而可大幅降低該切換士; 關電路5與整流濾波電路7其切換損失之功效 者，且同時更可提高節能之目的。 藉由以上詳細說明，可使熟知本項技蓺 明瞭本發明的確可達成前述目的，已符合：利 法之規定，爰提出專利申請。惟以上所 =本發明之較佳實施例而已，當不能以此限 疋亡發明貫施之範圍；故，凡依本發明申 利乾圍及說明書内容所作之簡單的等效變:盥 修飾，皆應仍屬本發明專利涵蓋之範圍内。/、 201240293 【圖式簡單說明】 公報證書第 電略之電路示 同步整流電源 〇 同步整流電源 D 同步整流開關 第1圖為習知中華民國專 M335874號之高效率推挽式電源 第2A圖為本發明脈波寬度調變之 裝置第一較佳實施例電路示意圖 第2B圖為本發明脈波寬度調變之 裝置第一較佳實施例方塊示意圖 第3圖為本發明切換開關電路今 電路之時序控制示意圖。 第4A圖為本發明脈波寬度調變之同步整流電源 裝置第二較佳實施例方塊示意圖。 第4 B圖為本發明脈波寬度調變之同步整流電源 裝置第二較佳實施例變頻電路之動作示音圖。 第4C圖為本發明脈波寬度調變之同步整流電源 裝置第二較佳實施例振盪訊號與脈波訊號之變 頻示意圖。 【主要元件符號說明】 1 :變壓器 11 : 一次側 12 :二次側 2 :變頻電路 21 .檢知電路 211 :轉換元件 201240293 2 2 :比例控制電路 2 3 :振盪電路 24 :取樣電路 3 :隔離電路 3 2 :隔離元件 4 :脈波寬度調變控制電路 4 0 :圖騰蜂放大電路 41 :延遲時序控制電路 5 :切換開關電路 6、 6a :同步整流開關電路 7、 7a :濾波電路 SI、S2、SRI、SR2、SRla、SR2a :金氧半場效 電晶體 81 :變壓器 811 :高壓側 81 2 :低壓側 82 :脈波寬度調變晶片 8 3 :調幅脈波放大電路 84 :隔離驅動變壓器 841 :高壓側 842 :低壓側Conversion to output (4) VFB comparison result π ϋ ϋ 负载 负载 负载 负载 负载 负载 负载 负载 负载 负载 负载 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 Therefore, when the load feedback power >1 v FB circuit 21 has its input terminal negative 21 and its output terminal is charged, the detection circuit apricot motor I FB rises. δ When the detection circuit 21 increases its output, the ratio 2 is controlled by the ratio: negative? The current IFB detection circuit ... and the oscillation power: two: terminal is connected to the control circuit 22 of this example. The 兮 鸲 is connected to the Μ Μ 电路 2 circuit 2! The load of the round end 201240293 current I FB flows into the proportional control circuit 22 its MOS half field effect transistor Q FB ' and the MOS half field effect transistor q FB Turning on, and at the same time, the 惺 current I t generates a shunt, and the § 玄 电流 current IA can flow into the MOS half field effect transistor qa, so that the MOS half field effect transistor q A can be turned on 'and thus the oscillation The charging current Ic of the circuit 23 becomes smaller, that is, the load current I FB rises to control the oscillation circuit 23 to decrease its charging current IC. Therefore, when the charging current ic decreases, the capacitor C can be slowly charged, and the voltage vc of the capacitor c can be increased by k, and the charging time t丨 of the capacitor C is increased. When the voltage vc of the capacitor c is charged to be equal to the internal voltage νι , the voltage vc of the capacitor C can be used to discharge the gold-oxygen half-effect transistor QB, and the oscillation circuit 23 can generate the oscillation signal 24, Moreover, the cycle time η can be increased 'at the same time, and the frequency of the oscillation signal E 24 is decreased by the inverse of the @ η 频率 frequency at the cycle, so as to reduce the frequency of the oscillation signal 24 . The pulse width modulation control circuit 4 can adjust the pulse width of the pulse width control circuit 4 to receive the oscillation signal generated by the vibration signal 23 so that: when the frequency of the oscillation signal 24 decreases, The LG: degree modulation control circuit 4 increases the on-time n 0N of the pulse signal 26 and the non-conduction time n _, and the total time T1 total of the period 201240293, which can increase the pulse cycle (duty CyCie). Moreover, the frequency of the pulse wave signal 26 can be decreased, so that the frequency of the pulse wave signal 26 can be reduced, and the pulse wave width modulation control circuit 4 can achieve the purpose of frequency conversion. The isolation circuit 3 is connected to the pulse width modulation control circuit 4, and the isolation circuit 3 is provided with an isolation element 32' to isolate the primary side 11 and the secondary side 12, and the isolation element 32 drives the switch. The circuit 5 must be driven after a low voltage is converted into a voltage, so a totem amplifier circuit 4 is added to the pulse width modulation control circuit 4, and the totem amplifier circuit 40 can make the isolation element 32 The output instantaneous current is required to drive the input capacitor (ClSS) of the switch circuit 5, so that it is easier to drive the switch circuit 5, and finally the totem amplifier circuit 4 is connected to the pulse width modulation control circuit. 4, and the pulse width modulation control circuit 4 is used to generate a control signal, which is amplified by the totem amplifier circuit 4, and then received by the isolation circuit 3 to drive the switch circuit 5. Of course, the pulse width modulation control circuit 4 has a delay timing control circuit which provides the delay timing control f. To the synchronous rectification switch, the delay control device can also be amplified by the totem 埠 amplification circuit 40, and then supplied to the synchronous rectification switch circuit 6. The isolation element 201240293 32 can be an isolation transformer. Again, the spacer element can also be an optocoupler, and the spacer element 32 can also be a magnetic element. Therefore, the present invention can adjust the frequency of the vibration signal 24 of the pulse width modulation chip 10 according to the light load and heavy load ratio of the load, and the pulse width modulation control circuit 4 can realize the frequency conversion of the pulse wave signal 26. The function 'in turn can greatly reduce the switch; the circuit 5 and the rectification filter circuit 7 have the effect of switching losses, and at the same time, the purpose of energy saving can be improved. From the above detailed description, it will be apparent to those skilled in the art that the present invention can achieve the foregoing objects and is in accordance with the provisions of the law. However, the above preferred embodiment of the present invention is not limited to the scope of the invention; therefore, the simple equivalent of the invention according to the present invention and the contents of the specification: It is still within the scope of the invention patent. /, 201240293 [Simple description of the diagram] The certificate of the certificate of the first circuit shows the synchronous rectification power supply 〇 synchronous rectification power supply D Synchronous rectifier switch Figure 1 is the high-efficiency push-pull power supply of the Chinese Republic of China M335874 No. 2A BRIEF DESCRIPTION OF THE DRAWINGS FIG. 2B is a block diagram of a first preferred embodiment of a pulse width modulation device according to the present invention. FIG. 3 is a circuit diagram of the switch circuit of the present invention. Schematic diagram of timing control. 4A is a block diagram showing a second preferred embodiment of a synchronous rectification power supply device for pulse width modulation according to the present invention. Fig. 4B is a diagram showing the action of the frequency conversion circuit of the second preferred embodiment of the synchronous rectification power supply device of the pulse width modulation of the present invention. FIG. 4C is a schematic diagram showing the frequency conversion of the oscillation signal and the pulse wave signal in the second preferred embodiment of the pulse-wave width modulation synchronous rectification power supply device of the present invention. [Main component symbol description] 1 : Transformer 11 : Primary side 12 : Secondary side 2 : Frequency conversion circuit 21 . Detection circuit 211 : Conversion element 201240293 2 2 : Proportional control circuit 2 3 : Oscillation circuit 24 : Sampling circuit 3 : Isolation Circuit 3 2 : Isolation Element 4 : Pulse Width Modulation Control Circuit 40 : Totem Bee Amplification Circuit 41 : Delay Timing Control Circuit 5 : Switching Switch Circuit 6 , 6a : Synchronous Rectification Switch Circuit 7 , 7a : Filter Circuits SI , S2 , SRI, SR2, SRla, SR2a: Gold Oxygen Half Field Effect Transistor 81: Transformer 811: High Voltage Side 81 2 : Low Voltage Side 82: Pulse Width Modulation Chip 8 3 : Amplitude Modulation Pulse Amplifier Circuit 84 : Isolation Drive Transformer 841 : High pressure side 842: low pressure side
8 5 :切換開關電路 8 6 :輸出整流電路 f ： DEAD TIME 15 201240293 99 :延遲時序 V FB :負載迴授電壓 V re f :内部電壓 I FB :負載電流 Q FB .金氧半場效電晶！ Q A 金氧半場效電晶體 I A 分電流 I C 充電電流 I t 恆電流 C 電容 V c 電壓 Q B 金氧半場效電晶體 V 1 内部電壓 11 充電時間 T1 週期時間 T1 ON :導通時間 T1 OFF ： 非導通時間 T1 total :週期總時間 Q1 開關元件 Q2 開關元件 168 5 : Switching circuit 8 6 : Output rectifier circuit f : DEAD TIME 15 201240293 99 : Delay timing V FB : Load feedback voltage V re f : Internal voltage I FB : Load current Q FB . Gold oxygen half-effect transistor! QA gold oxide half field effect transistor IA divided current IC charging current I t constant current C capacitor V c voltage QB gold oxygen half field effect transistor V 1 internal voltage 11 charging time T1 cycle time T1 ON : on time T1 OFF : non-conduction time T1 total : total cycle time Q1 switching element Q2 switching element 16