201249079 六、發明說明： 【發明所屬之技術領域】 本發明係指一種電源供應器之控制器及其相關電源供應器，尤 指一種低成本、單一電路晶片並具有高功率因素之電源供應器之控 制器及其相關電源供應器。 【先前技術】 電源供應器為電器產品中不可或缺的一部分，例如發光二極體 (Light Emitting Diode ’ LED )照明之應用。理想的電源供應器應具 有功率因素校正（P〇wer Factor Correction，PFC)功能，以確保交 流電流與電壓相位保持一致，並消除非理想之諧波，以提升功率因 素。 電源供應器應將輸出電壓、電流或電能維持在穩定的範圍内， 以確保電子裝錄狀安全及效率。因此’電源縣騎常係利用 來自其輸㈣之-回授路徑，以將輸出電壓、電流或電能維持於特 定範圍内。再者’基於安全考量，習知電源供應騎常會將-變壓 器之一次側與二次側互相隔離。 址5月參考第1圖’第1圖為一習知電源供應器1〇之示意圖。電源 供應器10係一反驰式(Fly-back)交換式電源供應器(SwitchingMode ，SMPS)，包含有—變壓器（Transfonner) 1〇〇、一電 201249079 晶體 102、一脈波寬度調變（Pulse Width Modulation，PWM)控制 單元104、一回授控制單元l〇6、一二極體l〇8 (作為整流功能）及 一電容C1。變壓器1〇〇包含有·--次侧繞組（Primary Side Winding ) NP以及一二次側繞組（Secondary Side Winding) Ns。回授控制單元 106包含有電阻Ri〜R4、一電容C2、一光搞合器（Photocoupler) 110 及一二端並聯穩壓器（Three-terminal Shunt Regulator ) 112。 電源轉換器10的電源轉換功能係透過脈寬調變控制單元104 控制電晶體102而實現。脈寬調變控制單元1〇4根據一來自於該回 授控制單元106之回授訊號VF，產生相對應之一控制訊號VPWM， 以控制電晶體102之導通及關閉。當電晶體1〇2導通時，電能儲存 於一次側繞組NP，此時整流器108因逆向偏壓而不導通，而電源轉 換器10之負載所需的電能由電容C1供應；當電晶體1〇2關閉時， 儲存於一次側繞組Np的電能傳遞至二次側繞組Ns，此時整流器1 〇 8 導通’而電能傳遞至負載。如第1圖所示，回授訊號VF是由三端並 聯穩壓器112驅動光耦合器110所產生。當電源轉換器10之一輸出 電壓V0UT上升或下降時，回授訊號vF隨之改變，進而改變控制訊 號Vpwm的工作週期（duty cycle)，以調整輸出至負載的電能，並使 輸出電壓V0UT維持穩定。三端並聯穩壓器112須配合其周邊元件以 達成其功能’其中電阻R1及幻用來將輸出電壓V0UT分壓以產生 一參考電壓’電阻R3及電容C2用來提供三端並聯穩壓器112所需 的迴路補償。 6 201249079 然而，此種二次側回授控制機制會加大電路面積及提高功率損 ^ ’且需使用高成本的元件以隔離該—次側與該二·，如光搞合 器及三端並聯麵ϋ。再者，為配合高功率輸出應用，該電路需使 用兩個獨立控制器ic，即PFC控制器及PWM控制器。如此一來， 不僅會增加電路設計複雜度，更提高生產成本。 【發明内容】 因此，本發明之主要目的即在於提供一種低成本，單一晶片， 並具有高功率因素之電源供應器。 人本發明揭露-種控制器，用於一電源供應器，該電源供應器包 含有一二次側繞組---次側繞組及-輔助繞組，關助繞組可產 生對應於该二次侧繞組一輸出電流之變化的一回授訊號，該控制器 包含有一功率開關，包含有一第一端耦接於該一次侧繞組，一第二 %及第二端，用來根據該第二端接收之一調變訊號，控制該第 一端與該第三端之間電性連結之導通，以及由該第三端產生一電流 感测λ號，一定電流區塊，用來根據該回授訊號以及該電流感測訊 號，產生一第一電流訊號；以及一控制單元，用來根據該第一電流 汛號、該回授訊號、該電流感測訊號及來自於該電源供應器之一電 壓訊4號’產生該調變訊號，以控制該功率開關。 本發明另揭露一種電源供應器，包含有一變壓器，包含一二次 側繞組，用來提供一二次側電流；一一次側繞組，用來提供一一次 201249079 側電流；以及-輔助繞組，用來產生對應於該二次側繞組一輸出電 流之變化的一回授訊號，該二次側電流與該一次側電流之間之一比 例為一定值；以及一控制器，包含一功率開關，包含有一第一端耦 接於該一次側’一第二端’及一第三端，用來根據該第二端接收之 一調變，控制3玄第一端與該第三端之間電性連結之導通，以及 由該第三端產生-電流感測訊號；—定電舰塊，用來根據該回授 訊號以及該電流感測訊號’產生一第一電流訊號；以及一控制單元， 用來根據該帛-電流纖、該喊喊、該電喊測職及來自於 該電源供應器之一電壓訊號’產生該調變訊號，以控制該功率開關。 【實施方式】 請參考第2圖’第2圖為本發明實施例一電源供應器2〇之示意 圖。電源供應器20係用來提供一輸出電壓v。以及一輸出電流I。至 一負載214，如複數個發光二極體。電源供應器2〇包含一變壓器 200、一功率開關Q卜一定電流區塊2〇6、一定電壓區塊2〇8、一控 制單元210及一電流感測電阻Rs。一交流輸入電壓ACin係經一橋 式整流電路222整流後’透過一分壓單元224產生--次側電壓訊 號乂。變壓器200包含有·次侧繞組（Primary Winding) NP以及 一二次側繞組（Secondary Winding) Ns，分別用來提供一一次側電 流Ip及一二次側電流Is。其中，二次側電流Is與一次側電流Ip之一 比例為一定值。變壓器200更包含一輔助繞組（Auxiliary Winding) NA ’可透過一回授節點AUX產生對應於該二次側繞組一輸出電流 I。之變化的一回授訊號VFB。輔助繞組Na係電感耦合至一次側繞組 8 201249079 NP及二次側繞組Ns，使得輔助繞組NA上之一電感電流IL可映射至 二次側繞組Ns上之二次側電流之變化。如此一來，自節點AUX產 生之回授訊號vFB係對應於輸出電流I。之變化。由於回授訊號Vfb 係來自電源供應器20之一次側，故此種回授機制被稱為一次側回授 控制架構。一次側回授控制相較於二次側回授控制之一優勢為不需 使用高成本元件，如光耦合器，並降低生產成本。 功率開關Q1係用來根據一接收到之調變訊號VMod，導通或切 斷一次側繞組NP上之一次側電流ip。功率開關Q1切斷時，一次側 電流Ip降至零，且電能轉移至二次側。當功率開關導通時，一 次侧電流Ip流過電流感測電阻Rs，並產生一對應於一次側電流Ip 之電流感測訊號CS。較佳地，功率開關qi可為一 N型金屬氧化半 導體（N type Metal-Oxide-Semiconductor ’ NMOS)，其汲極搞接於 變壓器200之一次側繞組Np (即電源供應器2〇之一次側），閘極耦 接於控制單元21G，以接收調變訊號V_，以域_接於電流感 測電阻Rs，以產生電流感測訊號CS。 因此，藉由控制功率開關Q1之導通或切斷，可控制由電源供 應器20之-次側傳送至二次側之電能，進而控制其輸出功率。調變 訊號％較佳地為-脈找度調變訊號，用來導通或切斷功率開關 Q卜藉此調控輸出電流Iq。任意其他可控制功率開關Q1之導通/切 斷狀態之訊號皆適用於本發明之電源供應器2G ^詳細而言，控制單 元210係透過變更脈波寬度調變訊號v譲之工作週期⑽㈣咖）， 201249079 以決定變壓器200之一次側繞組Np傳遞至二次側繞組Ns之能量大 小，並進一步地控制輪出電流 當調變訊號VMod* 一低電位轉換至一高電位時，功率開關Q1 導通，通過一次側繞組Np以及電流感測電阻Rs之一次側電流知漸 增。電流感測電阻Rs感應到一次侧電流Ip，因此產生電流感測訊號 CS至定電流區塊206。輸入電M ACin產生之電能儲辆一次側繞 組NP’此時二次側之一整流器226以及一次侧之一二極體2丨6因逆 向偏壓而不導通，故通過二次織組Ns的電流Is為零^當調變訊 號VM〇d使功率開M Q1被切斷時，儲存於一次側繞組^的電能傳 遞至二次側繞組Ns，導致通過二次峨組&的電流Is增加。由於 輔助繞組NA之能夠映射Is之變化，因此電感電流匕亦同步增加。 清參考第3圖’第3圖為本發明實施例第2圖中定電流區塊2〇6 之示意圖。定電流區塊206包含-波形偵測單元302、一運算單元 304、-誤差放大器3〇6以及一比較單元·。波形偵測單元撕係 輕接於電/域測電阻Rs，並絲_電流感測訊號cs之一波形， 以產生-操取訊號Vp。波形侧單元3〇2係偵測電流感測電阻^ 上之-次側電流IP ’以取得電流感測訊號cs之波形。 運算單元304 _於波形偵測單元3〇2，並用來分壓擁取訊號 p以產生選擇電壓Vx。運算單元3〇4係用來偵測回授訊號VpB 之放電週期Tdis (即二次側繞組Ns上之二次側電流Is遞減至零之 10 201249079 一放電週期）與回授訊號、之-職τ，並產生—_因子打 時間因子Tf可表示為[(TdwT) *κ]，其中民為一常數。運算 3〇4根據時間因子取娜訊號Vp，產生選擇電壓&選 Vx係擷取訊號Vp之一分壓結果，可表示為： 壓 ^Tdis i201249079 VI. Description of the Invention: [Technical Field] The present invention relates to a controller for a power supply and its associated power supply, and more particularly to a power supply with low cost, single circuit chip and high power factor. Controller and its associated power supply. [Prior Art] A power supply is an integral part of an electrical product, such as a Light Emitting Diode (LED) illumination application. The ideal power supply should have a P〇wer Factor Correction (PFC) function to ensure that the AC current is consistent with the voltage phase and eliminates non-ideal harmonics to improve power factor. The power supply should maintain a stable output voltage, current or power to ensure safe and efficient electronic loading. Therefore, the power supply county often uses the feedback path from its transmission (4) to maintain the output voltage, current or electrical energy within a specific range. Furthermore, based on safety considerations, the conventional power supply rider will normally isolate the primary side from the secondary side of the transformer. Referring to FIG. 1 in May, FIG. 1 is a schematic diagram of a conventional power supply unit. The power supply 10 is a fly-back switching power supply (SwitchingMode, SMPS), including a transformer (Transfonner) 1 , a battery 201249079 crystal 102, a pulse width modulation (Pulse) The Width Modulation (PWM) control unit 104, a feedback control unit 106, a diode l8 (as a rectifying function), and a capacitor C1. The transformer 1A includes a Primary Side Winding NP and a Secondary Side Winding Ns. The feedback control unit 106 includes resistors Ri to R4, a capacitor C2, a photocoupler 110, and a Three-terminal Shunt Regulator 112. The power conversion function of the power converter 10 is realized by controlling the transistor 102 through the pulse width modulation control unit 104. The pulse width modulation control unit 〇4 generates a corresponding one of the control signals VPWM according to a feedback signal VF from the feedback control unit 106 to control the turning on and off of the transistor 102. When the transistor 1〇2 is turned on, the electric energy is stored in the primary side winding NP, at which time the rectifier 108 is not turned on due to the reverse bias, and the electric energy required for the load of the power converter 10 is supplied by the capacitor C1; when the transistor 1〇 When 2 is turned off, the electric energy stored in the primary side winding Np is transmitted to the secondary side winding Ns, at which time the rectifier 1 〇 8 is turned on and the electric energy is transmitted to the load. As shown in Fig. 1, the feedback signal VF is generated by the three-terminal parallel regulator 112 driving the optical coupler 110. When the output voltage VOUT of the power converter 10 rises or falls, the feedback signal vF changes, thereby changing the duty cycle of the control signal Vpwm to adjust the power output to the load and maintain the output voltage VOUT. stable. The three-terminal shunt regulator 112 must cooperate with its peripheral components to achieve its function 'where resistor R1 and phantom are used to divide the output voltage VOUT to generate a reference voltage'. Resistor R3 and capacitor C2 are used to provide a three-terminal shunt regulator. 112 required loop compensation. 6 201249079 However, this secondary side feedback control mechanism will increase the circuit area and increase the power loss and use high cost components to isolate the secondary side and the second side, such as the optical combiner and the three ends. Parallel surface ϋ. Furthermore, to accommodate high power output applications, the circuit requires the use of two independent controllers, ic, the PFC controller and the PWM controller. As a result, not only will the circuit design complexity increase, but also the production cost. SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to provide a power supply that is low cost, single wafer, and has a high power factor. The invention discloses a controller for a power supply, the power supply comprising a secondary winding - a secondary winding and an auxiliary winding, the auxiliary winding can generate a secondary winding corresponding to the secondary winding An output signal of a change in output current, the controller includes a power switch including a first end coupled to the primary side winding, a second % and a second end for receiving according to the second end a modulation signal, controlling the conduction between the first end and the third end, and generating a current sensing λ number from the third end, the current block is used according to the feedback signal and The current sensing signal generates a first current signal; and a control unit is configured to use the first current signal, the feedback signal, the current sensing signal, and the voltage signal from the power supply. The number 'generates the modulation signal to control the power switch. The invention further discloses a power supply comprising a transformer comprising a secondary winding for providing a secondary current; a primary winding for providing a current of 201249079; and an auxiliary winding, a feedback signal for generating a change corresponding to an output current of the secondary winding, a ratio between the secondary current and the primary current is a fixed value; and a controller including a power switch, The first end is coupled to the first side of the first side and the third end for controlling the electrical connection between the first end and the third end according to the second end receiving The connection of the sexual connection, and the current sensing signal generated by the third end; the fixed electric power block is configured to generate a first current signal according to the feedback signal and the current sensing signal; and a control unit, And generating the modulation signal according to the 帛-current fiber, the shouting, the electric shouting test, and a voltage signal from the power supply to control the power switch. [Embodiment] Please refer to Fig. 2, which is a schematic view of a power supply unit 2 according to an embodiment of the present invention. The power supply 20 is used to provide an output voltage v. And an output current I. To a load 214, such as a plurality of light emitting diodes. The power supply 2A includes a transformer 200, a power switch Q, a constant current block 2〇6, a certain voltage block 2〇8, a control unit 210, and a current sensing resistor Rs. An AC input voltage ACin is rectified by a bridge rectifier circuit 222 to generate a secondary side voltage signal 透过 through a voltage dividing unit 224. The transformer 200 includes a Primary Winding NP and a Secondary Winding Ns for providing a primary side current Ip and a secondary side current Is, respectively. Among them, the ratio of the secondary side current Is to the primary side current Ip is a constant value. The transformer 200 further includes an auxiliary winding (NA) capable of generating an output current I corresponding to the secondary winding through a feedback node AUX. A feedback signal VFB of the change. The auxiliary winding Na is inductively coupled to the primary side winding 8 201249079 NP and the secondary side winding Ns such that one of the inductor currents IL on the auxiliary winding NA can be mapped to the change in the secondary side current on the secondary side winding Ns. As a result, the feedback signal vFB generated from the node AUX corresponds to the output current I. Change. Since the feedback signal Vfb is from the primary side of the power supply 20, this feedback mechanism is called a primary side feedback control architecture. One of the advantages of primary-side feedback control over secondary-side feedback control is that it does not require the use of high-cost components, such as optocouplers, and reduces production costs. The power switch Q1 is used to turn on or off the primary current ip on the primary winding NP according to a received modulated signal VMod. When the power switch Q1 is turned off, the primary side current Ip falls to zero, and the electric energy is transferred to the secondary side. When the power switch is turned on, the primary side current Ip flows through the current sensing resistor Rs, and generates a current sensing signal CS corresponding to the primary side current Ip. Preferably, the power switch qi can be an N-type metal-oxide-semiconductor (NMOS), and the drain is connected to the primary winding Np of the transformer 200 (ie, the primary side of the power supply 2) The gate is coupled to the control unit 21G to receive the modulation signal V_, and is connected to the current sensing resistor Rs to generate the current sensing signal CS. Therefore, by controlling the on or off of the power switch Q1, the power transmitted from the secondary side of the power supply 20 to the secondary side can be controlled, thereby controlling its output power. The modulation signal % is preferably a pulse-finding modulation signal for turning on or off the power switch Q to thereby regulate the output current Iq. Any other signal that can control the on/off state of the power switch Q1 is applicable to the power supply 2G of the present invention. ^ In detail, the control unit 210 transmits the duty cycle of the pulse width modulation signal v (10) (4). , 201249079 to determine the energy of the primary winding Np of the transformer 200 to the secondary winding Ns, and further control the wheel current. When the modulation signal VMod* is switched to a high potential, the power switch Q1 is turned on. The primary side current through the primary side winding Np and the current sense resistor Rs is gradually increased. The current sense resistor Rs senses the primary side current Ip, thus generating a current sense signal CS to the constant current block 206. The electric energy generated by the input power M ACin stores the primary winding NP'. At this time, one of the secondary side rectifier 226 and one of the primary side diodes 2丨6 are not turned on due to the reverse bias, so the secondary weave group Ns The current Is is zero. When the modulation signal VM〇d causes the power on M Q1 to be cut off, the electric energy stored in the primary winding ^ is transferred to the secondary winding Ns, resulting in an increase in the current Is through the secondary & group & . Since the auxiliary winding NA can map the change of Is, the inductor current 匕 also increases synchronously. 3 is a schematic view of a constant current block 2〇6 in the second embodiment of the present invention. The constant current block 206 includes a waveform detecting unit 302, an arithmetic unit 304, an error amplifier 3〇6, and a comparison unit. The waveform detecting unit tearing light is connected to the electric/domain measuring resistor Rs, and the waveform of the wire _ current sensing signal cs is generated to generate the operation signal Vp. The waveform side unit 3〇2 detects the current-side current IP' on the current sensing resistor^ to obtain the waveform of the current sensing signal cs. The arithmetic unit 304 is configured by the waveform detecting unit 3〇2 and is used to divide the grabbing signal p to generate the selection voltage Vx. The arithmetic unit 3〇4 is used to detect the discharge period Tdis of the feedback signal VpB (ie, the secondary side current Is on the secondary winding Ns is decremented to zero 10 201249079 one discharge period) and the feedback signal, the job τ, and the -_ factor time factor Tf can be expressed as [(TdwT) *κ], where the population is a constant. The operation 3〇4 takes the Na signal Vp according to the time factor, and generates a selection voltage & selects a voltage division result of the Vx system acquisition signal Vp, which can be expressed as: pressure ^Tdis i
Vy = Va τ 而電壓選擇單元304較佳地可為一數位—類比轉換器。 選擇賴Vx係疏於電職絲2G之輪㈣流卜其 郎可由中華民國專财請號嶋2週（與本發明相同申請者及發 明人）而知’選擇電壓^^可表示為： vv D NsVy = Va τ and voltage selection unit 304 is preferably a digital-to-analog converter. Choosing Lai Vx is neglecting the 2G wheel of the electric duty wire. (4) The flow of Buchilang can be obtained by the Republic of China for 2 weeks (the same applicant and inventor as the present invention). The selection voltage ^^ can be expressed as: vv D Ns
Rs*~*i〇*K TV尸 也就是說，定電流區塊2〇6可根據波形偵測單元3〇2及運算單 元3〇4 ’得到正比於輸出電流Ϊ。之選擇電壓Vx。簡單來說，輸 流I。係受到選擇電壓vx所控制。Rs*~*i〇*K TV Corp. In other words, the constant current block 2〇6 can be proportional to the output current 根据 according to the waveform detecting unit 3〇2 and the arithmetic unit 3〇4 ’. The selection voltage Vx. Simply put, the input I. It is controlled by the selection voltage vx.
v ref A ^如此· 誤差放大器306包含有兩輸入端，分別耦接於選擇電壓及 -參考電壓Vref4’其可將選擇電壓Vx之—最大值限制於第四^考 電壓Vref4之内。如此-來，輸出電流；!。之—最大輸出電流可 被限制至相關於第四參考電壓Vraf4之—穩定值。根據中華民國專利 申請號099123938’可進一步推得1(^“可表示為 J ，ύ 來，若電源供應器20之輪出電壓v。超過一可容忍電壓，輸出電流 I。可被限制至固定值，以保護電源供應器2〇之電路不至於損壞。除 201249079 此之外’穩定輸出電流I。可應用於相關的定電流電路，如發光二極 體照明等。 比較單元308係用來比較由誤差放大器306輸出之一第一比較 訊號co刪與-第-參考電壓Vren，並產生第—電流訊號i至控 制單元210。而一電壓儲存單元312係用來儲存誤差放大器3〇6輸 出之第一比較訊號COMPI。一比較器310係用來將一第一開關SW1 導通或切斷，以產生第一電流訊號。比較器31〇包含有一第一正 輸入端耦接於第一比較訊號COMPI ’ 一第二正輸入端耦接於第一參 考電壓Vref] ’以及-負輸入端輕接於一第一節點A。當兩個正輸入 *^其中之一的電壓向於負輸入端時（即當第一比較訊號C〇Mpi或 第-參考電壓vrefl其中之-高於第—節點八之電壓時），比較器 輸出-高準位電壓，以將第-開關SW1導通。當第一開關_被 導通時，一電流源C1將第一電流訊號g出至控制單元21〇。一電 阻（作為一負載）係耦接於第一節點A以及一接地端之間，且當來 自於電流源ci之m過貞载時，第-節點a之電壓隨即升高。 當第-節點A之電壓以及比較器31〇之負輪入端高於兩正輸入端之 電壓時，比較器310輸出-低電壓準位，以將第一開關_切斷。 第開關SW1為-二端元件，且較佳地可為一 N型金屬氧化物半 導體場效電晶體（N-typeM0SFET)，其雜_於電流源C1，闊 極搞接於比較器310，以及源極輕接於第一節點a。 至於運算單元304之實現方法，對本領域具通常知識者可進一 12 201249079 步參考中執國專辦賴嶋23938，（與本發明_申請及發明 人）其係利用一計數器以及多個開關，以實現運算單元304。因此， 本發明可不必利用複雜或昂貴的元件（例如積分器），即可實現定電 流區塊206，進而降低電源供應器2〇之生產成本。 電源供應器20可選擇性地包含一定電壓區塊2〇8，以提供電路 過電壓保顧制（〇vei*_VC)ltagepiOteetiGn)。料賴魏常知識者 可進一步參考中華民國專利申請號099125120 (與本發明相同申請 者及發明人）中定電壓區塊208之實現方法。請參考第4圖第4v ref A ^ Thus, the error amplifier 306 includes two inputs coupled to the selection voltage and the reference voltage Vref4', respectively, which limits the maximum value of the selection voltage Vx to the fourth voltage Vref4. So - come, output current;!. The maximum output current can be limited to a stable value associated with the fourth reference voltage Vraf4. According to the Republic of China Patent Application No. 099123938', it can be further derived that 1 (^" can be expressed as J, ,, if the voltage of the power supply 20 is v. Exceeding a tolerable voltage, the output current I can be limited to fixed. The value is to protect the circuit of the power supply 2〇 from damage. In addition to 201249079, the 'stable output current I can be applied to the relevant constant current circuit, such as LED illumination. The comparison unit 308 is used for comparison. A first comparison signal co is output from the error amplifier 306 to delete the -first reference voltage Vren, and a first current signal i is generated to the control unit 210. A voltage storage unit 312 is used to store the output of the error amplifier 3〇6. The first comparison signal COMPI is used to turn on or off a first switch SW1 to generate a first current signal. The comparator 31 includes a first positive input coupled to the first comparison signal COMPI. 'A second positive input terminal is coupled to the first reference voltage Vref] 'and a negative input terminal is connected to a first node A. When the voltage of one of the two positive inputs *^ is toward the negative input terminal ( That is when When the comparison signal C 〇 Mpi or the first reference voltage vref1 is higher than the voltage of the first node VIII, the comparator outputs a high level voltage to turn on the first switch SW1. When the first switch _ is turned on a current source C1 sends the first current signal g to the control unit 21A. A resistor (as a load) is coupled between the first node A and a ground terminal, and when the current source ci is passed When the load is on, the voltage of the first node a rises. When the voltage of the node A and the negative wheel of the comparator 31 are higher than the voltages of the two positive inputs, the comparator 310 outputs the low voltage level. The first switch _ is turned off. The first switch SW1 is a two-terminal element, and preferably may be an N-type metal oxide semiconductor field effect transistor (N-type MOSFET), which is mixed with the current source C1, The pole is connected to the comparator 310, and the source is lightly connected to the first node a. As for the implementation method of the arithmetic unit 304, those who have ordinary knowledge in the field can enter a 12 201249079 step reference in the special state of the country, Lai Yu 23938, (with The invention, the application and the inventor, utilizes a counter and a plurality of switches, The arithmetic unit 304 is implemented. Therefore, the present invention can realize the constant current block 206 without using complicated or expensive components (for example, an integrator), thereby reducing the production cost of the power supply 2. The power supply 20 can be selected. Optionally, a certain voltage block 2〇8 is included to provide a circuit overvoltage protection system (〇vei*_VC) ltagepiOteetiGn). It is expected that the knowledge of Wei Chang may further refer to the Republic of China Patent Application No. 099125120 (the same applicant as the present invention) And the inventor) how to implement the voltage block 208. Please refer to Figure 4, Figure 4.
圖為定電壓區塊208之示意圖。定電壓區塊2〇8可根據回授訊號I 之-膝點電壓（即通過二次側繞組Ns之電流骑為零時，辅助繞 組1^上之一電壓）’產生一第二電流訊號，並包含有一波峰偵測單 元402，用來根據回授訊號Vfb之一膝點電壓，產生一峰值電壓訊 號ve。波峰偵測單元402係由一電壓追蹤單元414及一取樣保持單 元416所組成；電壓追蹤單元414用來追踪回授訊號VpB，以輸出 一第一電壓訊號及一第一控制訊號Vde;取樣保持單元416耦接 於電壓追蹤單元414,用來取樣第一電壓訊號Vfr，以產生峰值電壓 訊號Ve。 簡單來說，當流經二次側繞組Ns之電流遞減至零時，回授訊 號vFB上產生之一膝點電壓係被電壓追蹤單元414追踪。取樣保持 單元416對電壓追蹤單元414之膝點電壓取樣，並產生一峰值電壓 訊號Ve。定電壓區塊亦產生一相對應之第二電流訊號％，使控制單 13 201249079 兀210產生調變訊號ν·，以控制功率開關之導通或切斷，進而控 制電源供應ϋ 2G之轉換轉。g此，當電驗應器Μ之負載產: 變化’並造成輪出電壓V。變動時（例如當負載214之一發光二極體 或祕）’喊喊VpB之膝點電壓亦對賴化。接著，波峰備 別單元402產生對應於回授訊號VpB之膝點電壓的一峰值電壓訊號 W，進而使控制料21〇根據回授訊號Vfb，產生具有適當工作週 』之調隻VMod。控制说號vM〇d係用來控制電晶體，並調 節傳遞至二次側之不同供電功率，賴f至不_負做用。誤差 放大器406及比較單元顿之運作類似於定電流區塊2〇6 ，故不在 此贅述。 请參考第5圖’第5圖為第2圖巾電源供應器2Q之控制單元 210之一實施例示意圖。控制單元21〇包含一設置單元5〇2、一重置 單元504及一 SR正反器506。設置單元502用來產生一設置訊號 Vset，重置單元504用來產生一重置訊號Vreset，而SR正反器5〇6則 根據設置訊號vset以及重置訊號Vreset，產生調變訊號VM〇d。 設置單元502包含一零電流偵測器518，用於偵測回授訊號Vfb 中之一零電流，並產生設置訊號Vset。詳細而言，當輔助繞組>^之 一電感電流IL遞減至零時，零電流偵測器518偵測到一零電流，並 輸出設置訊號Vset至SR正反器506。而SR正反器506進一步將調 變訊號VMod設為一高電壓準位「1」，以導通功率開關Q1。 201249079 重置單元504包含一電流相加單元5〇8、一輸入電壓單元51〇、 一誤差放大器512、一乘法器514以及一比較器516。電流相加單元 508分別將來自於定電流區塊206及定電壓區塊208之第一電流訊 號ii及第二電流訊號ιν相加，而產生一電流總和Is胃。輸入電壓單 元510則根據電流總和Isum，產生一反相電壓訊號。誤差放大器 512可限制反相電壓訊號Vinv不超過第一參考電壓Vren，並產生一 比較訊號COMP。乘法器514則對比較訊號c〇MP與來自於電源供 應器20之電壓訊號V〗進行乘法運算，並產生一電壓乘積V〆比較 器516係比較電壓乘積\^與電流感測訊號€5；，並產生重置訊號 Vreset。詳細而言，一旦功率開關Q1導通，一次側電流Ip上升，而 導致功率開關Q1源極之電流感測電阻rs的電壓亦隨即上升。誤差 放大器512係比較參考電壓vrefl與反相電壓訊號Vinv (其對應來自 定電流區塊206之第一電流訊號1〗與來自於定電壓區塊208之第二 電流訊號Iv之電流總和Isum)，並產生比較訊號COMP。接著，乘法 器514對比較訊號COMP與分壓自電源供應器20輸入電壓之一次 電壓訊號％ (對應於電源供應器20經整流後之直流輸入電壓）進 行相乘運算，並產生一電壓乘積Vm。接著，比較器516比較電壓乘 積Vm與電流感測訊號CS。若電流訊號CS高於電壓乘積Vm，則比 較器516輸出重置訊號Vreset至SR正反器506，以產生一低電壓準 位之調變訊號VMod ’進而將功率開關Q1切斷。第6B圖為電壓乘 積Vm及電流感測訊號CS經比較後，產生調變訊號vMod之示意圖。 簡單來說’藉由根據調變訊號VMod，交替設置或重置SR正反 15 201249079 器506，以將功率開關Q1導通或切斷，一次側電流&之平均電流 Ip_avg的波形將隨著直流輸人電I 之波形變動，使—次側電流^ 及直流輸入電壓Vi之間達到同相位，因此可得到高功率因素，並The figure is a schematic diagram of a constant voltage block 208. The constant voltage block 2〇8 can generate a second current signal according to the knee voltage of the feedback signal I (ie, when the current of the secondary winding Ns is zero, the voltage on the auxiliary winding 1) And including a peak detecting unit 402 for generating a peak voltage signal ve according to a knee voltage of the feedback signal Vfb. The peak detecting unit 402 is composed of a voltage tracking unit 414 and a sample holding unit 416. The voltage tracking unit 414 is configured to track the feedback signal VpB to output a first voltage signal and a first control signal Vde. The unit 416 is coupled to the voltage tracking unit 414 for sampling the first voltage signal Vfr to generate a peak voltage signal Ve. Briefly, when the current flowing through the secondary side winding Ns is decremented to zero, one of the knee point voltages generated on the feedback signal vFB is tracked by the voltage tracking unit 414. The sample hold unit 416 samples the knee voltage of the voltage tracking unit 414 and generates a peak voltage signal Ve. The constant voltage block also generates a corresponding second current signal %, so that the control unit 13 201249079 兀210 generates a modulation signal ν· to control the power switch to be turned on or off, thereby controlling the power supply ϋ 2G conversion. g This, when the load of the electrical tester is produced: change 'and causes the voltage V to be turned. When changing (for example, when one of the loads 214 emits a diode or a secret), the voltage at the knee of the VpB is also shouted. Then, the peak matching unit 402 generates a peak voltage signal W corresponding to the knee voltage of the feedback signal VpB, thereby causing the control material 21 to generate a VMOD having an appropriate working period according to the feedback signal Vfb. The control number vM〇d is used to control the transistor and adjust the different power supply to the secondary side, depending on whether it is used or not. The operation of the error amplifier 406 and the comparison unit is similar to the constant current block 2〇6, and therefore will not be described here. Please refer to Fig. 5, which is a schematic diagram of an embodiment of the control unit 210 of the second towel power supply 2Q. The control unit 21A includes a setting unit 5〇2, a reset unit 504, and an SR flip-flop 506. The setting unit 502 is configured to generate a setting signal Vset, the reset unit 504 is configured to generate a reset signal Vreset, and the SR flip-flop 5〇6 generates a modulation signal VM〇d according to the setting signal vset and the reset signal Vreset. . The setting unit 502 includes a zero current detector 518 for detecting one of the zero currents of the feedback signal Vfb and generating the setting signal Vset. In detail, when the inductor current IL of the auxiliary winding > is decremented to zero, the zero current detector 518 detects a zero current and outputs the set signal Vset to the SR flip-flop 506. The SR flip-flop 506 further sets the modulation signal VMod to a high voltage level "1" to turn on the power switch Q1. 201249079 The reset unit 504 includes a current adding unit 5〇8, an input voltage unit 51〇, an error amplifier 512, a multiplier 514, and a comparator 516. The current adding unit 508 adds the first current signal ii and the second current signal ιν from the constant current block 206 and the constant voltage block 208, respectively, to generate a current sum Is stomach. The input voltage unit 510 generates an inverted voltage signal based on the current sum Isum. The error amplifier 512 can limit the inverted voltage signal Vinv not to exceed the first reference voltage Vren and generate a comparison signal COMP. The multiplier 514 multiplies the comparison signal c〇MP with the voltage signal V from the power supply 20, and generates a voltage product V 〆 comparator 516 is a comparison voltage product ^ ^ and current sensing signal € 5; And generate a reset signal Vreset. In detail, once the power switch Q1 is turned on, the primary side current Ip rises, and the voltage of the current sense resistor rs of the source of the power switch Q1 also rises. The error amplifier 512 compares the reference voltage vref1 with the inverted voltage signal Vinv (which corresponds to the first current signal 1 from the constant current block 206 and the current sum Isum from the second current signal Iv of the constant voltage block 208). And generate a comparison signal COMP. Next, the multiplier 514 multiplies the comparison signal COMP with a primary voltage signal % of the input voltage from the power supply 20 (corresponding to the rectified DC input voltage of the power supply 20), and generates a voltage product Vm. . Next, the comparator 516 compares the voltage product Vm with the current sense signal CS. If the current signal CS is higher than the voltage product Vm, the comparator 516 outputs the reset signal Vreset to the SR flip-flop 506 to generate a low voltage level modulation signal VMod' to turn off the power switch Q1. Fig. 6B is a schematic diagram showing the modulation signal vMod after the voltage product Vm and the current sensing signal CS are compared. Simply put, by alternately setting or resetting the SR forward/reverse 15 201249079 506 according to the modulation signal VMod, the power switch Q1 is turned on or off, and the waveform of the primary current & average current Ip_avg will follow the direct current. The waveform of the input power I changes so that the secondary side current ^ and the DC input voltage Vi are in phase, so that a high power factor can be obtained, and
於南電壓雜時上升，並且制—由€縣積^所決定之峰值電 感電流。當神開關Q1被切斷時，電感電流隨即下降。電感電流 之-零電齡致使功相關φ再度導通，故可制波形與、同相 位之-平均輸人電流Ip_avg。因此，平均輸人電gpavg與輸入電壓The south voltage rises when it is mixed, and the peak-inductance current is determined by the county. When the god switch Q1 is turned off, the inductor current drops. The zero-electricity of the inductor current causes the work-related φ to be turned on again, so that the waveform and the same-phase-average input current Ip_avg can be formed. Therefore, the average input power gpavg and input voltage
Vi亦同相位，故電源供應器2〇具有高功率因素。控制單元2ι〇亦 可在第-電流減Ii (對應於輸出電流〗。）或第二電流訊號L (對 應於輸出電壓V。）過高時，切斷神_ Φ，故鶴供應器加可 提供穩定如電流及輸th電壓。因此，電雜應㈣可祕各種定 電流應用，例如發光二極體光源等。再者，電源供應器20具有過電 壓保護機制，故可輸料同輪出鱗^_負載。請參考第7圖，Vi is also in phase, so the power supply 2 has a high power factor. The control unit 2ι can also cut off the god _ Φ when the first current minus Ii (corresponding to the output current) or the second current signal L (corresponding to the output voltage V) is too high, so the crane supply can be added Provides stability such as current and th voltage. Therefore, electrical hybrids (4) can be used for various fixed current applications, such as light-emitting diode sources. Moreover, the power supply 20 has an overvoltage protection mechanism, so that it can transport the same wheel to the scale. Please refer to Figure 7,
nVf則為η個發光二棰體串聯時之一輸出電壓 雷懕V,B主，Β,丨帝浪瓜處3& a h _ . 第7圖為本發明實施例電源供應器2G之輸出電壓v。對輸 I 之示意圖 /;IL n I。則逐漸1 會被控制Η 照明電路， 之一輸出龍。當輸㈣壓V。超過nVf is one of the output voltages of the n-light emitting diodes in series. The output voltage of the power supply 2G is the output voltage of the power supply 2G of the embodiment of the present invention. . Schematic diagram of the input I /; IL n I. Then gradually 1 will be controlled by the lighting circuit, one of which outputs the dragon. When the (four) pressure V. exceed
201249079 部電路。 因此，當輸出電壓V〇超過一可容忍準位時，電源供應器2〇可 提供狱的輸丨電流iGMax，以供需要定電流之_顧，並避免輸 出電流過大而造成電源供應器20損壞。簡言之，定電流區塊可透過 波形偵測單元3〇2以及運算單元3(M，求得與輸出電流】。成正比之 選擇電壓vx，並將麵電壓Vx關在參考電壓U，使得最大輸 出電流I〇Max被限制在一定值，以供定電流之相關應用。 &上所述’本發明可達到—具有高功率因素之電雜應器，並 可透過-次側回授機制以避免使用昂貴且複雜元件（如以光耗合器 達到電源供應器-次及二次側隔離），進而降低成本。同時，本發明 可透過=流區塊及定電魏塊，提供輸出功率之調節，且不需使 用複雜或《:卩責的電路元件（例如積分器、三端並聯穩壓器朴再者， 根據树明，功率因素校正、脈波紐職（PWM)以及功率調節 控制等功i自可利用單-電路晶片實現，因此可縮小電路面積，降 低不必要之功率消耗，且降低製造成本。 以上所述僅為本發明之較佳實施例，凡依本發明申請專利範 所做之均等變倾料，皆應屬本㈣之涵蓋範圍。 【圖式簡單說明】 第1圖為一習知電源供應器之示意圖。 201249079 第2圖為本發明實施例一電源供應器之示意圖。 第3圖為本發明實施例第2圖中定電流區塊之示意圖。 第4圖為本發明實施例第2圖中定電壓區塊之示意圖。 第5圖為本發明實施例第2圖中控制單元之示意圖。 第6A、6B圖為本發明實施例第2圖中電源供應器之波形之示 意圖。 第7圖為本發明實補電源供應器之輸出賴對輸出電流之示 意圖。 【主要元件符號說明】 10、20 電源供應器 100、102 變壓器 104 脈波寬度調變控制單元 106 回授控制單元 110 光耦合器 112 三端並聯穩壓器 200 變壓器 204 電晶體 206 定電流區塊 208 定電壓區塊 210 控制單元 214 負載 201249079 216 二極體 222 橋式整流電路 224 分壓單元 226 整流器 302 波形偵測單元 304 運算單元 306、406、512 誤差放大器 308、408 比較單元 310、410、516 比較器 402 波峰偵測單元 414 電壓追縱單元 416 取樣保持單元 502 設置單元 504 重置單元 506 SR正反器 508 電流相加單元 510 輸入電壓單元 514 乘法器 518 零電流偵測器 Vfb 回授訊號 cs 電流感測訊號 Np 一次側繞組 19 201249079201249079 Department circuit. Therefore, when the output voltage V〇 exceeds a tolerable level, the power supply 2〇 can provide the inrush current iGMax of the prison for the need of constant current, and avoid the output current is too large and the power supply 20 is damaged. . In short, the constant current block can select the voltage vx in proportion to the waveform detecting unit 3〇2 and the arithmetic unit 3 (M, and obtain the output current), and close the surface voltage Vx to the reference voltage U. The maximum output current I 〇 Max is limited to a certain value for the application of the constant current. & The above-mentioned invention can achieve - an electric hybrid with high power factor, and can pass the -sub-back feedback mechanism In order to avoid the use of expensive and complicated components (such as the power supply to the power supply - secondary and secondary side isolation), thereby reducing the cost. At the same time, the present invention can provide output power through the = flow block and the fixed power block Adjustments, and do not need to use complex or ": blame circuit components (such as integrator, three-terminal shunt regulator Park again, according to Shuming, power factor correction, pulse wave (PWM) and power adjustment control The iso-function i can be realized by using a single-circuit wafer, thereby reducing the circuit area, reducing unnecessary power consumption, and reducing manufacturing cost. The above is only a preferred embodiment of the present invention, and the patent application according to the present invention Made Equivalent variable dumping should be covered by this (4). [Simple description of the drawing] Figure 1 is a schematic diagram of a conventional power supply. 201249079 Figure 2 is a schematic diagram of a power supply according to an embodiment of the present invention. 3 is a schematic diagram of a constant current block in the second embodiment of the present invention. FIG. 4 is a schematic diagram of a constant voltage block in the second embodiment of the present invention. FIG. 5 is a second embodiment of the present invention. 6A and 6B are schematic diagrams showing the waveform of the power supply in the second embodiment of the present invention. Fig. 7 is a schematic diagram showing the output current of the actual complementary power supply of the present invention. Description 10, 20 power supply 100, 102 transformer 104 pulse width modulation control unit 106 feedback control unit 110 optical coupler 112 three-terminal shunt regulator 200 transformer 204 transistor 206 constant current block 208 constant voltage region Block 210 Control Unit 214 Load 201249079 216 Diode 222 Bridge Rectifier Circuit 224 Voltage Dividing Unit 226 Rectifier 302 Waveform Detection Unit 304 Operation Units 306, 406, 512 Difference amplifier 308, 408 Comparison unit 310, 410, 516 Comparator 402 Wave detection unit 414 Voltage tracking unit 416 Sample holding unit 502 Setting unit 504 Reset unit 506 SR flip-flop 508 Current adding unit 510 Input voltage unit 514 Multiplier 518 Zero Current Detector Vfb Feedback Signal cs Current Sense Signal Np Primary Side Winding 19 201249079
Ns 二次側繞組 Na 輔助繞組 V〇 輸出電壓 I〇 輸出電流 ^Mod 調變訊號 Vset 設置訊號 ^ reset 重置訊號 Vm 電壓乘積 Isum 電流總和Ns secondary winding Na auxiliary winding V〇 output voltage I〇 output current ^Mod modulation signal Vset setting signal ^ reset reset signal Vm voltage product Isum current sum