、發明說明： 【發明所屬之技術領域】 本發明是有關於一種電源轉換系統，特別是指一種能 使單一直流電壓源產生多組不同升降電壓值輸出之數位電 視移動接收器之電源轉換系統。 【先前技術】 數位電視移動接收器（Mobile STB)是使用在汽車上用以 接收數位電視郎目之數位訊號編碼器。在電源設計一般是 使用車用電瓶的直流電壓（DC)12伏特做為輸入電源，再透 過直流對直流電壓轉換電路及電壓調節器（Regulat〇r IC)以 降壓輸出一個適當的直流電壓值。然而此種高電壓在轉換 成低電壓的過程中容易產生發熱情形，這對於嚴格要求溫 度之車用商品而言並不完全符合所需，且所需成本亦較高 ’更鮮有多輸出之設計。 因此，本發明之目的，即在提供一種藉由脈寬調變電 路取代習用之直流對直流電壓轉換電路，不僅能避免降壓 過程產生發熱，更能分割出多個不同的電壓輸出，以供應 多個不同電子裝置所需之數位電視移動接收器之電源轉換 系統。 於疋，本發明數位電視移動接收器之電源轉換系統， 包含有一用以提供直流電源之電源輸入單元、一電性連接 該電源輸入單元之脈寬調變單元、一功率切換單元、一昇 降壓型電源轉換單元，以及一降壓型電源轉換單元。該脈 寬調變單元具有-脈寬調變電路，以及—個以上與該脈寬 1220590 調變電路電性連接且用以調變該脈寬調變電路輸出不同訊 號脈寬之驅動控制電路。該功率切換單元與該等驅動控制 電路電性連接，而依各該驅動控制電路所輸出之不同訊號 脈寬以切換不同功率輸出。該昇降壓型電源轉換單元具有 一轉換器，以及一第一回授電路，該轉換器則具有一用與 該功率切換單元電性連接且透過該功率切換單元而接收一 驅動控制電路輸出訊號之輸入端，以及複數個分別與各該 遽波器電性連接之輸出端，該第一回授電路並與該轉換器 之一輸出端電性連接，並使該輸出端之輸出電壓回授至該 脈寬調變電路，用以作為該脈寬調變電路檢知與該轉換器 相對應之驅動控制電路輸出電壓是否穩定。該降壓型電源 轉換單元具有一與該功率切換單元電性連接且透過該功率 切換單元而輸出另一驅動控制電路輸出訊號之電源輸出端 ’以及一與該電源輸出端電性連接之第二回授電路，藉該 第二回授電路使得該電源輸出端之輸出電壓回授至該脈寬 調變電路，用以作為該脈寬調變電路檢知與該電源輸出端 相對應之驅動控制電路輸出電壓是否穩定。 本發明之功效在於能使單一直流電源轉換形成多個不 同的直電壓輸出，且能避免高電壓轉換成低電壓過程中產 生發熱現象，同時更能降低成本。 【實施方式】 有關本發明之别述及其他技術内容、特點與功效，在 以下配合參考圖式之一較佳實施例的詳細說明中，將可清 楚的明白。 6 1220590 5 如圖1、2所示，本發明數位電視移動接收器之電源 轉換系統一較佳實施例，該電源轉換系統1包含有一用以 提供直流電源之電源輸入單元2、一電性連接該電源輸入單 元2之脈寬調變單元3、一功率切換單元4、一昇降壓型電 源轉換單元5，以及一降壓型電源轉換單元6。 10 電源輸入單元2具有一第一電連接器21及一第二電連 接器22，第一電連接器21具有多個連接埠，在本例中是以 6個做說明，其中有兩個連接埠（即接腳①、②）是用為連接 至車輛電瓶12伏特（V)、一連接埠（即接腳④)接地、一連接 蟑（即接_)是用以控制系統啟動與$，而其他接腳（即接腳 ⑤⑥）則可用以與車輛之音響等等電子裝置電性連接。另外 ，用為連接至車輛電瓶12v之兩連接埠（即接腳①、②）更可 外接至第二連接器22，以使12伏特的電瓶電源仍可單獨提 供使用。 15 20 脈寬調變單元3具有-與第一連接器21之兩連接蜂（即 接腳①、②）電性連接以接收12伏特電瓶電壓之脈寬調變電 路31，以及兩分別與脈寬調變電路3丨電性連接之第一、一 驅動控制電路32、33。脈寬調變電路31輸出㈣之高低取 決於其週期（Duty)脈寬大小，即在_個週期内脈波位於⑽ 的時間愈長，輸出電壓就愈高。 力率切換單4具有-用以接收第_驅動控制電路％ 輪出訊號之第一切換開關4卜及一與第一切換開關Μ、第 二驅動控制電路33電性連接之第二切換開關42，各該切換 開關4卜42可為金氧半場效電晶體_fet)。第—切換開 7 1220590 關41及第二切換開關42之内部均設置有一大電流驅動電 路及一小電流驅動電路（圖中未示）。 昇降壓型電源轉換單元5具有一轉換器（Transformer)51 、複數個第一遽波器52，以及一第一回授電路53，該轉換 器51係為變壓器，是由複數線圈纏繞而形成一次側端（即接 腳①、②側）及與該一次側端串聯之二次側端（即接腳③、④ 、⑤側），於一次侧端形成有一輸入端（即接腳①），並藉由線 圈匝數比不同而形成複數輸出端（即接腳②、③、④、⑤）， 且因線圈是由一次側端往二側端逐漸纏繞，因此繞線圈圈 數以接腳②最少，接腳⑤最多，即接腳②的輸出電壓最低， 其次是接腳③、④，以接腳⑤的輸出電壓最高。輸入端(即接 腳①)並與第-、二切換開關41、42中之小電流驅動電路電 41之輸出電壓。前述Description of the invention: [Technical field to which the invention belongs] The present invention relates to a power conversion system, and more particularly to a power conversion system for a digital television mobile receiver capable of generating multiple sets of output voltages with different voltages from a single DC voltage source. [Prior Art] Digital TV Mobile Receiver (Mobile STB) is a digital signal encoder used in cars to receive digital TV Langmu. In the power supply design, the DC voltage (12V) of the vehicle battery is generally used as the input power, and then a DC-to-DC voltage conversion circuit and a voltage regulator (Regulator IC) are used to step down to output an appropriate DC voltage value. However, such high voltages are prone to generate heat during the conversion into low voltages. This is not entirely suitable for automotive products that strictly require temperature, and the required cost is also higher. design. Therefore, the object of the present invention is to provide a pulse-width modulation circuit instead of the conventional DC-to-DC voltage conversion circuit, which can not only avoid heat generation during the voltage step-down process, but also can divide a plurality of different voltage outputs to Power conversion system for digital TV mobile receivers required to supply multiple different electronic devices. The power conversion system of the digital television mobile receiver of the present invention includes a power input unit for providing a DC power supply, a pulse width modulation unit electrically connected to the power input unit, a power switching unit, and a step-up / down voltage. Power conversion unit, and a step-down power conversion unit. The pulse width modulation unit has a pulse width modulation circuit, and more than one drive electrically connected to the pulse width 1220590 modulation circuit and used to modulate the pulse width modulation circuit to output different signal pulse widths. Control circuit. The power switching unit is electrically connected to the driving control circuits, and switches different power outputs according to different signal pulse widths output by the driving control circuits. The step-up and step-down power conversion unit has a converter and a first feedback circuit, and the converter has a circuit that is electrically connected to the power switching unit and receives a drive control circuit output signal through the power switching unit. An input terminal, and a plurality of output terminals electrically connected to each of the wave generators, the first feedback circuit is electrically connected to one output terminal of the converter, and the output voltage of the output terminal is fed back to The PWM circuit is used as the PWM circuit to detect whether the output voltage of the drive control circuit corresponding to the converter is stable. The step-down power conversion unit has a power output terminal that is electrically connected to the power switching unit and outputs another driving control circuit output signal through the power switching unit, and a second power output terminal that is electrically connected to the power output terminal. A feedback circuit, by which the output voltage of the power output terminal is fed back to the pulse width modulation circuit by the second feedback circuit, and is used as the pulse width modulation circuit to detect that it corresponds to the power output terminal Whether the drive control circuit output voltage is stable. The effect of the present invention is that a single DC power source can be converted to form a plurality of different direct voltage outputs, and a heating phenomenon can be avoided in the process of converting a high voltage to a low voltage, and at the same time, the cost can be reduced. [Embodiment] The other descriptions of the present invention and other technical contents, features and effects will be clearly understood in the following detailed description of a preferred embodiment with reference to the accompanying drawings. 6 1220590 5 As shown in Figures 1 and 2, a preferred embodiment of a power conversion system for a digital television mobile receiver according to the present invention. The power conversion system 1 includes a power input unit 2 for providing a DC power source, and an electrical connection. The power input unit 2 has a pulse width modulation unit 3, a power switching unit 4, a buck-boost power conversion unit 5, and a step-down power conversion unit 6. 10 The power input unit 2 has a first electrical connector 21 and a second electrical connector 22. The first electrical connector 21 has a plurality of ports. In this example, six are used for description, two of which are connected. Ports (ie pins ① and ②) are used to connect to the vehicle battery 12 volts (V), a port (ie pin ④) is grounded, and a connection cock (ie _) is used to control system startup and $, The other pins (ie, pins ⑤⑥) can be used to electrically connect with the vehicle's audio and other electronic devices. In addition, the two ports (ie pins ①, ②) used to connect to the vehicle battery 12v can also be connected to the second connector 22 so that the 12-volt battery power can still be provided separately. 15 20 The pulse width modulation unit 3 has a pulse width modulation circuit 31 that is electrically connected to two connection bees (ie, pins ①, ②) of the first connector 21 to receive a 12-volt battery voltage, and two The pulse width modulation circuit 3 is electrically connected to the first and first driving control circuits 32 and 33. The level of output ㈣ of the pulse width modulation circuit 31 depends on the period (Duty) pulse width, that is, the longer the pulse wave is at ⑽ in _ period, the higher the output voltage. The power rate switching sheet 4 has a first switching switch 4 for receiving the _th driving control circuit and a second switching switch 42 electrically connected to the first switching switch M and the second driving control circuit 33. Each of the changeover switches 4 and 42 may be a metal-oxide half field effect transistor (FET). The first—switching on 7 1220590 off 41 and the second switching switch 42 are each provided with a large current driving circuit and a small current driving circuit (not shown in the figure). The buck-boost power conversion unit 5 includes a converter 51, a plurality of first wavers 52, and a first feedback circuit 53. The converter 51 is a transformer and is formed by winding a plurality of coils once. The side ends (ie, the pins ①, ② side) and the secondary side ends (ie, the pins ③, ④, ⑤ side) connected in series with the primary side end form an input end (ie, the pin ①) at the primary side end, A plurality of output terminals (ie, pins ②, ③, ④, ⑤) are formed by different coil turns ratios, and because the coil is gradually wound from the primary side to the two sides, the number of turns around the coil is the pin ②. At least, pin ⑤ is the most, that is, the output voltage of pin ② is the lowest, followed by pins ③, ④, and the output voltage of pin ⑤ is the highest. The input terminal (i.e., pin ①) and the output voltage of the small-current driving circuit 41 in the second and second switching switches 41 and 42. Previously
性連接’用以接收第一、二切換開關 各弟一;慮波電路52並分別與轉換器 ⑤、④）電性連接，進而分別外接出端 為昇壓輸出端，接腳②、③電性連"Sexual connection" is used to receive one of the first and second switch; the wave circuit 52 is electrically connected to the converters ⑤, ④), and the external output terminals are boost output terminals, and the pins ② and ③ are electrically connected. Sexual connection
一、二切換開關41、42 6具有一與功率切換單元4之第 之大電流驅動電路電性連接之電源 8 1220590 5 輪出端（即端點E)、-電性連接於端點E與第…二切換開 關41、42之大電流驅動電路間之第二濾波器η，以及一分 別與端點E、脈寬調變電路31電性連接之第二回授電路^ 。當然只要透過端ϋ E另外接—可用以調變端點e電壓之 電壓調整器63,再由電壓調整器63輸出端外接出—端點f ’即可再增加-直流電壓輸出端，由於此部份乃屬電子電 路習常慣用之技術手段’於圖2中並未予以顯示。 10 15 藉此12伏特電瓶電壓輸入脈寬調變電路31後，經轉 換成脈波訊號而分別輸入第一、二驅動控制電路32、Μ， 利用各驅動控制電路32、33所設計的工作點不同，而將脈 寬調變電路31所輸出之脈波訊號調變成兩個不同脈寬的脈 波訊號，並分別輸入第一、二切換開g 41、42，在本例中 ，由第-驅動控制電路32輸入第一、二切換開關41 “2 之小電流驅動電路之脈波訊號電壓值是設定為5伏特，而 由第二驅動控制電路33輸入第一、二切換開關41、42大 電流驅動電路之脈波訊號電壓值是設定為2·5伏特。 20 第-切換開關41進-步將所接收到的5伏特脈寬訊號 透過轉換器51之接腳①輸入轉換器51中，此時c端點處的 電壓（即轉換器51之接腳②、③之電壓）為5伏特。此5伏特 電壓值再藉由電壓調整器54調變為3·3伏特而成為端點D 處之電壓。另外，再利用線圈纏繞匝數之漸增而使端點Β 及Α處之電壓分別提高為12伏特及3〇伏特。另外，接腳 ②、③的5伏特電壓值也可經由第一回授電路53輸入脈寬 調變電路31，使得脈寬調變電路31可根據此一回授電壓值 9 第一驅動控制電路32輸出電壓是否穩定。 而第二切換開關42所接收到的Μ伏特電壓值將可由 變為：輪出，同時透刪調整器63將25伏特電壓值調 5 …、·8伏特後再由端點F輸出。另外，端點E之電壓值 ，·伏/寺更可透過第二回授電路62而輸人脈寬調變電路Μ 酿說脈寬调交電路31可根據此一回授電壓值而檢知第二 ·’動控制電路33輸出電壓是否穩定。 、在本例中端點A、B、C、卜E、F處之電麼值30、12 - —3·3 2.5及1.8伏特僅為一示例說明而已，當然也可謂 1〇 #由調整脈寬調變電路31所輸出之訊號脈寬大小，而使各 電壓值有不同之變化。 另外，本發明電源轉換系統i利用單一輸入直流電壓（ P 12伏特電瓶電壓）而能轉換形成多個直流電麼輸出（如川 、12、5、3·3、2.5及1·8伏特）’以提供作為更多種車用電 15 +裝置所需之電力來源’不僅更具使用之便利性，同時在 電壓轉換過程中僅會產生微發熱現象，設計上也能達到降 低使用成本之優點。 _ 歸.内上述，本發明數位電視移動接收器之電源轉換系 統，藉由脈寬調變電路31外接兩驅動控制電路32、33，而 2〇 使輸人脈寬調變電路31之單—直流電Μ可被調變成兩個不 同脈寬電壓訊號，同時透過兩切換開關41、42及轉換器5 ^ 而進一步產生多個直流電壓輸出，因此能提供作為更多種 車用電子裝置所需之電力來源’且在電廢轉換過程中也僅 會微量發熱’使用上更加便利，同時亦能有效降低使用成 10 1220590 成本，而能確實達到上述本發明之目的。 5 惟以上所述者，僅為本發明之較佳實施例而已，當不 能以此限定本發明實施之範圍，即大凡依本發㈣請專利 範圍及發明說明書内容所作之簡單的等效變化與修飾，皆 應仍屬本發明專利涵蓋之範圍内。 【圓式簡單說明】 圖1是本發明數位電視移動接收器之電源轉換系統一 較佳實施例之系統方塊圖；及 圖2是較佳實施例之電路圖。 10The first and second switching switches 41 and 42 6 have a power supply 8 1220590 5 which is electrically connected to the first high-current driving circuit of the power switching unit 4 (the terminal E), which is electrically connected to the terminal E and The second filter η between the second high-current drive circuits of the second switching switches 41 and 42 and a second feedback circuit ^ electrically connected to the terminal E and the pulse width modulation circuit 31 respectively. Of course, as long as it is connected through terminal ϋE—a voltage regulator 63 that can be used to adjust the voltage at terminal e, and then the output of voltage regulator 63 is externally connected—terminal f 'can be added again—the DC voltage output terminal. Some of them are common technical techniques used in electronic circuits' and are not shown in FIG. 2. 10 15 The 12-volt battery voltage is input to the pulse width modulation circuit 31, and then converted into a pulse wave signal and input to the first and second drive control circuits 32 and M, respectively. The work designed by each of the drive control circuits 32 and 33 is used. The point is different, and the pulse wave signal output by the pulse width modulation circuit 31 is tuned into two pulse wave signals with different pulse widths, and the first and second switching signals g 41 and 42 are respectively input. In this example, The first drive control circuit 32 inputs the first and second changeover switches 41 "2, the pulse signal voltage value of the small current drive circuit is set to 5 volts, and the second drive control circuit 33 inputs the first and second changeover switches 41, 42 The pulse signal voltage value of the high-current drive circuit is set to 2.5V. 20 The-switch 41 further advances the received 5V pulse width signal through the pin of the converter 51 ① Input the converter 51 At this time, the voltage at the end of c (that is, the voltage of the pins ② and ③ of the converter 51) is 5 volts. This 5 volt voltage value is adjusted to 3 · 3 volts by the voltage regulator 54 and becomes the terminal. The voltage at point D. In addition, the increasing number of turns The voltages at points B and A are increased to 12 volts and 30 volts respectively. In addition, the 5 volt voltage values of pins ② and ③ can also be input to the pulse width modulation circuit 31 through the first feedback circuit 53 to make the pulse width The modulation circuit 31 can determine whether the output voltage of the first driving control circuit 32 is stable according to the feedback voltage value 9. The M volt voltage value received by the second switch 42 can be changed to: turn out, and at the same time transparently delete The regulator 63 adjusts the 25 volt voltage value to 5…, 8 volts and then outputs it from the terminal F. In addition, the voltage value of the terminal E, volts / temple can be input to the pulse width through the second feedback circuit 62 The modulation circuit M and the pulse width modulation circuit 31 can detect whether the output voltage of the second motion control circuit 33 is stable based on this feedback voltage value. In this example, the endpoints A, B, C, The electrical values at E and F are 30, 12-3. 3 2.5 and 1.8 volts are just an example. Of course, it can also be referred to as 10 # the pulse width of the signal output by the pulse width modulation circuit 31 In addition, each voltage value has different changes. In addition, the power conversion system i of the present invention uses a single input DC voltage (P 12 Special battery voltage) and can be converted to form multiple DC power outputs (such as Sichuan, 12, 5, 3, 3, 2.5 and 1.8V) to provide the power source required for more types of vehicle power 15+ devices 'It is not only more convenient to use, but also only generates a slight heating phenomenon during the voltage conversion process, and the design can also achieve the advantage of reducing the use cost. _ Attribution. As mentioned above, the power conversion system of the digital television mobile receiver of the present invention The pulse width modulation circuit 31 is externally connected with two driving control circuits 32 and 33, and the single-input DC current M which is input to the pulse width modulation circuit 31 can be adjusted to two different pulse width voltage signals at the same time. Through the two switching switches 41, 42 and the converter 5 ^, multiple DC voltage outputs are further generated, so it can provide the power source required for more types of automotive electronic devices' and only a small amount of heat is generated during the power waste conversion process. 'It is more convenient to use, and at the same time, it can effectively reduce the cost of use into 10 1220590, and can indeed achieve the above-mentioned object of the present invention. 5 However, the above are only the preferred embodiments of the present invention. When the scope of implementation of the present invention cannot be limited by this, that is, the simple equivalent changes made according to the scope of the patent and the contents of the invention specification Modifications should still fall within the scope of the invention patent. [Circular brief description] FIG. 1 is a system block diagram of a preferred embodiment of a power conversion system of a digital television mobile receiver according to the present invention; and FIG. 2 is a circuit diagram of the preferred embodiment. 10
11 1220590 【圊式之主要元件代表符號說明】 1電源轉換系統 3脈寬調變單元 5昇降壓型電源轉換單元 21第一電連接器 3 1脈寬調變電路 3 3第二驅動控制電路 42第二切換開關 52第一濾波器 61第二濾波器 63電壓調整器 A、B、C、D、E、F 端點 2電源輸入單元 4功率切換單元 6降壓型電源轉換單元 22第二電連接器 32第一驅動控制電路 41第一切換開關 5 1轉換器 53第一回授電路 62第二回授電路 1211 1220590 [Description of the main symbols of the main components] 1 Power conversion system 3 Pulse width modulation unit 5 Buck-boost power conversion unit 21 First electrical connector 3 1 Pulse width modulation circuit 3 3 Second drive control circuit 42 Second switch 52 First filter 61 Second filter 63 Voltage regulator A, B, C, D, E, F Terminal 2 Power input unit 4 Power switching unit 6 Step-down power conversion unit 22 Second Electrical connector 32 first drive control circuit 41 first switch 5 1 converter 53 first feedback circuit 62 second feedback circuit 12