TWM470387U

TWM470387U - Multiple-specification mixing-use LED chip driving device

Info

Publication number: TWM470387U
Application number: TW102217431U
Authority: TW
Inventors: Ming-Feng Lin
Original assignee: Hep Tech Co Ltd; Ming-Feng Lin
Priority date: 2013-09-16
Filing date: 2013-09-16
Publication date: 2014-01-11

Description

多規格混用之發光二極體晶片驅動裝置Multi-standard mixed light emitting diode chip driving device

本創作係與發光二極體驅動有關；特別是指一種多規格混用之發光二極體晶片驅動裝置。This creation is related to the driving of the LED; in particular, it refers to a multi-standard hybrid LED driving device.

按，發光二極體照明裝置係包含有一發光二極體晶片與一驅動裝置，該驅動裝置用以提供該發光二極體晶片所需之電能。目前市面上的發光二極體晶片規格琳瑯滿目，舉例而言，以下五種不同規格的發光二極體晶片，45V/500mA、38V/700mA、34V/900mA、20V/1500mA、14V/1400mA，其額定電壓及額定電流皆不同，因此，額電功率也不盡相同。即使是具有相同功率的發光二極體晶片，其額定電壓與額定電流之組合亦是繁多。為了驅動如此多種規格組合的發光二極體晶片，現有的方式是針對每一種規格的發光二極體晶片開發一種驅動裝置。然，對於發光二極體照明裝置製造商而言，開發的驅動裝置種類增多不但增加驅動裝置庫存的壓力，而且無法以量制價，導致製造成本居高不下。若能開發適用於多規格的發光二極體晶片之驅動裝置，當可降低發光二極體晶片之驅動裝置庫存的壓力，並且有效降低製造成本。According to the LED illumination device, a light-emitting diode chip and a driving device for supplying the electric energy required for the LED chip are provided. At present, the specifications of the LED chips on the market are numerous. For example, the following five different specifications of the LED chip, 45V/500mA, 38V/700mA, 34V/900mA, 20V/1500mA, 14V/1400mA, are rated. The voltage and rated current are different, so the frontal power is not the same. Even in the case of a light-emitting diode chip having the same power, the combination of the rated voltage and the rated current is also numerous. In order to drive a light-emitting diode wafer of such a plurality of specifications, the existing method is to develop a driving device for each size of the light-emitting diode wafer. However, for manufacturers of light-emitting diode lighting devices, the increase in the number of types of driving devices developed has not only increased the pressure on the inventory of the driving devices, but also prevented the price from being priced, resulting in high manufacturing costs. If a driving device suitable for a multi-standard light-emitting diode chip can be developed, the pressure on the inventory of the driving device of the light-emitting diode chip can be reduced, and the manufacturing cost can be effectively reduced.

有鑑於此，本創作之目的在於提供一種多規格混用之發光二極體晶片驅動裝置，可適用於驅動多種不同規格的發光二極體晶片。In view of this, the purpose of this creation is to provide a multi-standard hybrid LED driving device that can be used to drive a variety of different specifications. Light-emitting diode chip.

緣以達成上述目的，本創作所提供多規格混用之發光二極體晶片驅動裝置，包含有：一輸入埠、一輸出埠、一驅動單元、一電壓偵測單元與一回授控制模組，其中，該輸入埠電性連接一電源；該輸出埠供電性連接一發光二極體晶片或一電源供應裝置，該電源供應裝置輸出一輸出電壓；該驅動單元電性連接該輸入埠與該輸出埠，其中，該輸出埠電性連接該發光二極體晶片時，該驅動單元接收該電源的電能並輸出一驅動電壓與一驅動電流予該發光二極體晶片；該電壓偵測單元電性連接該輸出埠，偵測該輸出埠的電壓之電壓值；該回授控制模組電性連接該電壓偵測單元及該驅動單元，該回授控制模組內建有一預設功率值，在該輸出埠電性連接該發光二極體晶片時，該回授控制模組依據該電壓偵測單元所測得的驅動電壓之電壓值及該預設功率值，控制該驅動單元使該驅動電流持維於符合該發光二極體晶片的額定電流之電流值；在該輸出埠電性連接該電源供應裝置時，該電源供應裝置輸出該輸出電壓至該輸出埠，且該回授控制模組記錄該電壓偵測單元所測得的輸出電壓之電壓值的數值，並將記錄的數值取代該預設功率值。In order to achieve the above objective, the present invention provides a multi-standard hybrid LED driving device comprising: an input port, an output port, a driving unit, a voltage detecting unit and a feedback control module. The input port is electrically connected to a power source; the output port is electrically connected to a light emitting diode chip or a power supply device, and the power supply device outputs an output voltage; the driving unit is electrically connected to the input port and the output In the case where the output is electrically connected to the LED, the driving unit receives the power of the power source and outputs a driving voltage and a driving current to the LED chip; the voltage detecting unit is electrically Connecting the output port to detect the voltage value of the voltage of the output port; the feedback control module is electrically connected to the voltage detecting unit and the driving unit, and the feedback control module has a preset power value built therein. When the output is electrically connected to the LED chip, the feedback control module controls the drive according to the voltage value of the driving voltage measured by the voltage detecting unit and the preset power value. The unit maintains the driving current at a current value corresponding to the rated current of the LED chip; when the output is electrically connected to the power supply device, the power supply device outputs the output voltage to the output port, and the The feedback control module records the value of the voltage value of the output voltage measured by the voltage detecting unit, and replaces the recorded value with the preset power value.

藉此，本創作多規格混用之發光二極體晶片驅動裝置，可供驅動多種不同規格的發光二極體晶片，有效改善習用的驅動裝置只能用於驅動一種規格之發光二極體晶片的缺點。Therefore, the multi-standard hybrid LED chip driving device of the present invention can be used to drive a plurality of different-sized LED chips, thereby effectively improving the conventional driving device and can only be used for driving a standard LED chip. Disadvantages.

1‧‧‧驅動裝置1‧‧‧ drive

1a‧‧‧輸入埠1a‧‧‧Input埠

1b‧‧‧輸出埠1b‧‧‧ Output埠

10‧‧‧驅動單元10‧‧‧Drive unit

20‧‧‧電壓偵測單元20‧‧‧Voltage detection unit

30‧‧‧電流偵測單元30‧‧‧current detection unit

40‧‧‧回授控制模組40‧‧‧Feedback control module

42‧‧‧運算單元42‧‧‧ arithmetic unit

44‧‧‧控制單元44‧‧‧Control unit

50‧‧‧發光二極體晶片50‧‧‧Light Emitter Wafer

60‧‧‧電源供應裝置60‧‧‧Power supply unit

P‧‧‧電源P‧‧‧Power supply

圖1為本創作一較佳實施例之驅動裝置連接發光二極體晶片方塊圖；圖2為本創作一較佳實施例之驅動裝置連接電源供應裝置方塊圖；1 is a block diagram of a driving device connected to a light emitting diode chip according to a preferred embodiment of the present invention; 2 is a block diagram of a power supply device for connecting a driving device according to a preferred embodiment of the present invention;

為能更清楚地說明本創作，茲舉較佳實施例並配合圖示詳細說明如后，圖1所示者為本創作第一較佳實施例多規格混用之發光二極體晶片驅動裝置1，包含有一輸入埠1a、一輸出埠1b、一驅動單元10、一電壓偵測單元20、一電流偵測單元30、一回授控制模組40。In order to explain the present invention more clearly, the preferred embodiment will be described in detail with reference to the accompanying drawings. As shown in FIG. 1 , the first preferred embodiment of the present invention is a multi-standard hybrid light-emitting diode driving device 1 . The device includes an input port 1a, an output port 1b, a driving unit 10, a voltage detecting unit 20, a current detecting unit 30, and a feedback control module 40.

該輸入埠1a電性連接一電源P，該輸出埠1b供使用者選擇地電性連接一發光二極體晶片50或一電源供應裝置60，該電源供應裝置60具有一輸出埠602，該電源供應裝置60自該輸出埠602輸出一輸出電壓。The input port 1a is electrically connected to a power source P. The output port 1b is selectively electrically connected to a light emitting diode chip 50 or a power supply device 60. The power supply device 60 has an output port 602. The supply device 60 outputs an output voltage from the output port 602.

該驅動單元10電性連接該輸入埠1a與該輸出埠1b，該發光二極體晶片50電性連接至該輸出埠1b後，該驅動單元10接收該電源P的電能並輸出一驅動電壓與一驅動電流予該發光二極體晶片50。該驅動單元10係可受控制地改變該驅動電壓之電壓值與該驅動電流之電流值。在實務上，該驅動單元10可為採用PWM、半橋式、Buck、Boost等型式的電路為基礎進行設計。該發光二極體晶片50係可選自額定功率相同但不同額定電壓與額定電流規格的發光二極體晶片50。The driving unit 10 is electrically connected to the input port 1a and the output port 1b. After the LED chip 50 is electrically connected to the output port 1b, the driving unit 10 receives the power of the power source P and outputs a driving voltage and A driving current is applied to the light emitting diode chip 50. The driving unit 10 can controllably change the voltage value of the driving voltage and the current value of the driving current. In practice, the drive unit 10 can be designed based on circuits of the PWM, half bridge, Buck, Boost, and the like. The LED wafer 50 can be selected from a light-emitting diode wafer 50 having the same rated power but different rated voltages and rated current specifications.

該電壓偵測單元20電性連接該驅動單元10及該輸出埠1b，用以偵測該驅動單元10供輸予該發光二極體晶片50的驅動電壓之電壓值。該電流偵測單元30電性連接該驅動單元10及該輸出埠1b，用以偵測該驅動單元10供輸予該發光二極體晶片50的驅動電流之電流值。The voltage detecting unit 20 is electrically connected to the driving unit 10 and the output port 1b for detecting the voltage value of the driving voltage of the driving unit 10 for the driving diode 50. The current detecting unit 30 is electrically connected to the driving unit 10 and the output port 1b for detecting the current value of the driving current supplied by the driving unit 10 to the LED chip 50.

該回授控制模組40包含有相互電性連接的一運算單元42與一控制單元44。該運算單元42電性連接該電壓偵測單元20與該電流偵測單元30，該控制單元44電性連接該驅動單元10。該運算單元42內建有一預設功率值及一比較電壓值，該驅動單元10所連接的發光二極體晶片50的額定功率需與該預設功率值相同或相近，較佳地，所選用的發光二極體晶片50的額定功率介於該預設功率值的90%~110%間。The feedback control module 40 includes one electrically connected to each other The arithmetic unit 42 and a control unit 44. The computing unit 42 is electrically connected to the voltage detecting unit 20 and the current detecting unit 30. The control unit 44 is electrically connected to the driving unit 10. The operating unit 42 has a preset power value and a comparison voltage value. The rated power of the LED chip 50 connected to the driving unit 10 needs to be the same or similar to the preset power value. Preferably, the selected power is used. The rated power of the LED wafer 50 is between 90% and 110% of the preset power value.

該發光二極體晶片50電性連接至該輸出埠1b後，該運算單元42依據該電壓偵測單元20所測得的驅動電壓之電壓值及該預設功率值進行計算，以取得該發光二極體晶片50所需之一工作電流值，其中該工作電流值係符合所連接的發光二極體晶片50額定電流。該運算單元42透過該控制單元44輸出一電流控制訊號至該驅動單元10使該驅動電流之電流值持維於該工作電流值。After the LED device 50 is electrically connected to the output port 1b, the computing unit 42 calculates the voltage value of the driving voltage measured by the voltage detecting unit 20 and the preset power value to obtain the light. One of the operating current values required for the diode wafer 50, wherein the operating current value is in accordance with the rated current of the connected LED chip 50. The computing unit 42 outputs a current control signal to the driving unit 10 via the control unit 44 to maintain the current value of the driving current at the operating current value.

在本實施例中，該運算單元42透過該控制單元44發送該電流控制訊號控制該驅動單元10使該驅動單元10輸出的驅動電流之電流值由一小於該工作電流值的啟始電流值逐漸增加，同時該運算單元42透過該電壓偵測單元20及該電流偵測單元30偵測該驅動電壓之電壓值及該驅動電流之電流值，並計算該驅動電壓之電壓值與該驅動電流之電流值的一乘積(即施加於該發光二極體晶片50上的驅動功率)。可輕易了解的是，供予該發光二極體晶片50的該驅動電壓之電壓值係隨著該驅動單元10所供輸的驅動電流之電流值的提升而增加，因此，施加於該發光二極體晶片50上的驅動功率亦隨之增加，直到施加於該發光二極體晶片50上的驅動功率達到該預設功率值時停止增加該驅動電流之電流值，此際的驅動電流之電流值即為該工作電流值，藉此，可對應得到該發光二極體80所需之工作電流值。在實務上，除了以計算方式得到該工作電流值外，亦可在出廠前先測試多個發光二極體操作於啟始電流值時的電壓值，再將所測得的電壓值與該些發光二極體晶片的對應關係建立於資料庫中，藉此，發光二極體晶片50連上驅動單元10，供輸啟始電流值並測量對應的電壓值，依據測得的電壓值即可由資料庫中擷取出所需之工作電流值。In this embodiment, the operation unit 42 sends the current control signal through the control unit 44 to control the driving unit 10 to make the current value of the driving current output by the driving unit 10 gradually increase from a starting current value smaller than the working current value. The operating unit 42 detects the voltage value of the driving voltage and the current value of the driving current through the voltage detecting unit 20 and the current detecting unit 30, and calculates the voltage value of the driving voltage and the driving current. A product of the current value (i.e., the driving power applied to the LED chip 50). It can be easily understood that the voltage value of the driving voltage supplied to the LED chip 50 increases as the current value of the driving current supplied by the driving unit 10 increases, and therefore, is applied to the LED 2 The driving power on the polar body wafer 50 is also increased, and the current value of the driving current is stopped when the driving power applied to the LED body 50 reaches the preset power value, and the current of the driving current is interrupted. The value is the operating current value, whereby the operating current value required for the light-emitting diode 80 can be obtained. In reality In addition, in addition to obtaining the working current value by calculation, the voltage values of the plurality of LEDs operating at the starting current value may be tested before leaving the factory, and the measured voltage values and the illuminating values may be detected. The correspondence between the diode chips is established in the database, whereby the LED chip 50 is connected to the driving unit 10 for inputting the starting current value and measuring the corresponding voltage value, and the data can be obtained according to the measured voltage value. The required operating current value is taken out of the library.

該運算單元42透過該控制單元44發送該電流控制訊號控制該驅動單元10，使該驅動電流之電流值維持於該發光二極體晶片50所需之工作電流值，以供輸符合該預設功率值的該驅動功率至該發光二極體晶片50，使該發光二極體晶片50達到定功率之狀態，換言之，此時的驅動電壓之電壓值與驅動電流之電流值的乘積維持於設定的預設功率值。The operation unit 42 sends the current control signal to the control unit 44 to control the driving unit 10 to maintain the current value of the driving current at the operating current value of the LED chip 50 for the transmission to meet the preset. The driving power of the power value is applied to the LED chip 50 to bring the LED chip 50 to a constant power state. In other words, the product of the voltage value of the driving voltage and the current value of the driving current is maintained at the setting. The preset power value.

在該發光二極體晶片50自該輸出埠1b取下後，該控制單元44控制該驅動單元10停止輸出驅動電壓及驅動電流。請配合圖2所示，將該電源供應裝置60的輸出埠602電性連接至該輸出埠1b，此時，該電壓偵測單元20偵測該電源供應裝置60的輸出電壓，該運算單元42比對該電壓偵測單元20所偵測的該輸出電壓之電壓值與該比較電壓，當該電壓偵測單元20所偵測的該輸出電壓之電壓值大於或等於該比較電壓值時，該運算單元42記錄該電壓偵測單元20所偵測的輸出電壓之電壓值的數值，並將記錄的數值取代原有的該預設功率值，而成為新的該預設功率值。接著，將該電源供應裝置60的輸出埠602自該輸出埠1b取下，以阻斷該電源供應裝置60與該驅動裝置1之間的電性連接，即完成該預設功率值的設定。After the LED chip 50 is removed from the output port 1b, the control unit 44 controls the driving unit 10 to stop outputting the driving voltage and the driving current. As shown in FIG. 2, the output port 602 of the power supply device 60 is electrically connected to the output port 1b. At this time, the voltage detecting unit 20 detects the output voltage of the power supply device 60. The operation unit 42 Comparing the voltage value of the output voltage detected by the voltage detecting unit 20 with the comparison voltage, when the voltage value of the output voltage detected by the voltage detecting unit 20 is greater than or equal to the comparison voltage value, The computing unit 42 records the value of the voltage value of the output voltage detected by the voltage detecting unit 20, and replaces the original value with the recorded value to become the new preset power value. Then, the output port 602 of the power supply device 60 is removed from the output port 1b to block the electrical connection between the power supply device 60 and the driving device 1, that is, the setting of the preset power value is completed.

舉例而言，該運算單元42內建的比較電壓值為30V，而原來的該預設功率值為40W，若欲將該預設功率值更改為32W時，則將該電源供應裝置60的輸出電壓調整為32V，再將該電源供應裝置60電性連接至該驅動裝置1的輸出埠1b。此時，該電壓偵測單元20測得該輸出電壓之電壓值為32V，而該運算單元42判斷該輸出電壓之電壓值大於該比較電壓值(30V)，因此將數值"32"設定為新的該預設功率值32W。接著將該電源供應裝置60的輸出埠602自該驅動裝置1的輸出埠1b取下，即完成該預設功率值的設定。如此，該驅動裝置1即可適用於驅動額定功率為32W的發光二極體晶片50。For example, the comparison voltage value built in the operation unit 42 is 30V, and the original preset power value is 40W, if the preset power value is to be used. When the value is changed to 32 W, the output voltage of the power supply device 60 is adjusted to 32 V, and the power supply device 60 is electrically connected to the output 埠 1b of the drive device 1. At this time, the voltage detecting unit 20 measures that the voltage value of the output voltage is 32V, and the operation unit 42 determines that the voltage value of the output voltage is greater than the comparison voltage value (30V), so the value "32" is set to new. The preset power value is 32W. Then, the output port 602 of the power supply device 60 is removed from the output 埠1b of the driving device 1, that is, the setting of the preset power value is completed. Thus, the driving device 1 can be adapted to drive a light-emitting diode wafer 50 having a rated power of 32W.

據上所述，該驅動裝置1可自動偵測所連接的發光二極體晶片50維持於該預設功率值所需之工作電流值，即使替換成不同額定電壓及額定電流的發光二極體晶片50，只要其額定功率與該預設功率值相同或相近，皆可適用於該驅動裝置1。該驅動裝置1可供驅動多種不同規格的發光二極體晶片50，有效改善習用的驅動裝置只能用於驅動一種規格的發光二極體晶片之不便。更值得一提的是，透過將該電源供應裝置60電性連接至該驅動裝置1的輸出埠1b，即可利用該電源供應裝置60的輸出電壓之電壓值的數值取代原有的該預設功率值，使該驅動裝置1可適用於驅動不同額定功率的發光二極體晶片50。According to the above, the driving device 1 can automatically detect the working current value required for the connected LED chip 50 to maintain the preset power value, even if the LED is replaced with a different rated voltage and rated current. The wafer 50 can be applied to the driving device 1 as long as its rated power is the same as or similar to the preset power value. The driving device 1 can drive a plurality of different sizes of the LED chips 50, which effectively improves the inconvenience that the conventional driving device can only be used to drive a standard LED chip. It is further worth mentioning that by electrically connecting the power supply device 60 to the output port 1b of the driving device 1, the value of the voltage value of the output voltage of the power supply device 60 can be used instead of the original preset. The power value allows the drive unit 1 to be adapted to drive light-emitting diode wafers 50 of different power ratings.

以上所述僅為本創作較佳可行實施例而已，舉凡應用本創作說明書及申請專利範圍所為之等效變化，理應包含在本創作之專利範圍內。The above is only a preferred embodiment of the present invention, and equivalent changes to the scope of the present application and the scope of the patent application are intended to be included in the scope of the present patent.

1‧‧‧驅動裝置1‧‧‧ drive

1a‧‧‧輸入埠1a‧‧‧Input埠

1b‧‧‧輸出埠1b‧‧‧ Output埠

10‧‧‧驅動單元10‧‧‧Drive unit

20‧‧‧電壓偵測單元20‧‧‧Voltage detection unit

30‧‧‧電流偵測單元30‧‧‧current detection unit

40‧‧‧回授控制模組40‧‧‧Feedback control module

42‧‧‧運算單元42‧‧‧ arithmetic unit

44‧‧‧控制單元44‧‧‧Control unit

50‧‧‧發光二極體晶片50‧‧‧Light Emitter Wafer

P‧‧‧電源P‧‧‧Power supply

Claims

一種多規格混用之發光二極體晶片驅動裝置，包含有：一輸入埠，電性連接一電源；一輸出埠，供電性連接一發光二極體晶片或一電源供應裝置，該電源供應裝置輸出一輸出電壓；一驅動單元，電性連接該輸入埠與該輸出埠，其中，該輸出埠電性連接該發光二極體晶片時，該驅動單元接收該電源的電能並輸出一驅動電壓與一驅動電流予該發光二極體晶片；一電壓偵測單元，電性連接該輸出埠，偵測該輸出埠的電壓之電壓值；以及一回授控制模組，電性連接該電壓偵測單元及該驅動單元，該回授控制模組內建有一預設功率值，在該輸出埠電性連接該發光二極體晶片時，該回授控制模組依據該電壓偵測單元所測得的驅動電壓之電壓值及該預設功率值，控制該驅動單元使該驅動電流持維於符合該發光二極體晶片的額定電流之電流值；在該輸出埠電性連接該電源供應裝置時，該電源供應裝置輸出該輸出電壓至該輸出埠，且該回授控制模組記錄該電壓偵測單元所測得的輸出電壓之電壓值的數值，並將記錄的數值取代該預設功率值。A multi-standard hybrid LED driving device comprises: an input port electrically connected to a power source; an output port electrically connected to a light emitting diode chip or a power supply device, the power supply device output An output voltage; a driving unit electrically connecting the input port and the output port, wherein the output unit is electrically connected to the LED chip, the driving unit receives the power of the power source and outputs a driving voltage and a Driving a current to the LED chip; a voltage detecting unit electrically connecting the output port to detect a voltage value of the output port; and a feedback control module electrically connected to the voltage detecting unit And the driving unit, the feedback control module has a preset power value, and when the output is electrically connected to the LED chip, the feedback control module is measured according to the voltage detecting unit. a voltage value of the driving voltage and the preset power value, controlling the driving unit to maintain the driving current at a current value corresponding to the rated current of the LED chip; and electrically connecting the output The power supply device outputs the output voltage to the output port, and the feedback control module records the value of the voltage value of the output voltage measured by the voltage detecting unit, and replaces the recorded value with the value The preset power value.

如請求項1所述多規格混用之發光二極體晶片驅動裝置，其中該回授控制模組控制該驅動單元使該驅動電流之電流值由一啟始電流值逐漸增加，同時偵測供輸至該發光二極體晶片的驅動電壓之電壓值，並計算該驅動電壓之電壓值與該驅動電流之電流值的一乘積，直到該乘積等於該預設功率值時停止增加並維持該驅動電流之電流值。The multi-standard hybrid LED driving device of claim 1, wherein the feedback control module controls the driving unit to gradually increase the current value of the driving current from a starting current value, and simultaneously detect and supply a voltage value of a driving voltage to the light emitting diode chip, and calculating a voltage value of the driving voltage And a product of the current value of the drive current, until the product is equal to the preset power value, stopping increasing and maintaining the current value of the drive current.

如請求項2所述多規格混用之發光二極體晶片驅動裝置，包含有一電流偵測電路，電性連接該輸出埠與該回授控制模組，該電流偵測電路偵測該驅動電流之電流值；該回授控制模組依據所偵測的該驅動電流之電流值與所偵測的該驅動電壓之電壓值計算該乘積。The multi-standard hybrid LED chip driving device of claim 2 includes a current detecting circuit electrically connected to the output port and the feedback control module, wherein the current detecting circuit detects the driving current The current value; the feedback control module calculates the product according to the detected current value of the driving current and the detected voltage value of the driving voltage.

如請求項1所述多規格混用之發光二極體晶片驅動裝置，其中該驅動單元所連接的發光二極晶片之額定功率介於該預設功率值的90%~110%間。The multi-standard hybrid LED chip driving device of claim 1, wherein the rated power of the light-emitting diode chip connected to the driving unit is between 90% and 110% of the preset power value.

如請求項1所述多規格混用之發光二極體晶片驅動裝置，其中該回授控制模組更內建有一比較電壓值，該回授控制模組比對該電壓偵測單元所測得的輸出電壓之電壓值大於或等於該比較電壓值時，該回授控制模組將所記錄的輸出電壓之電壓值的數值取代該預設功率值。The multi-standard hybrid LED driving device of claim 1, wherein the feedback control module further has a comparison voltage value, and the feedback control module is compared to the voltage detection unit. When the voltage value of the output voltage is greater than or equal to the comparison voltage value, the feedback control module replaces the value of the voltage value of the recorded output voltage with the preset power value.