201101918 六、發明說明： 【發明所屬之技術領域】 [0001] 本發明涉及一種控制技術，尤其涉及一種應用於投影機 内的LED控制電路。 【先前技術】 [0002] LED有著功耗低，壽命長，體積小，光利用率高等優點， 而隨著技術的發展，LED替代傳統的照明燈泡並應用在各 領域内已經成為現實。 0 [0003] LED應用在投影機領域内’就是得益于高亮度LED技術的 發展；由於LED有著長達10萬小時壽命，因此，比起傳統 的鹵素燈泡或者高壓汞燈泡3000小時左右壽命，其優勢 是十分明顯的。led使投影的壽#大大提高，因此以前 制約投影機發展的因素得以解決，使得投影機市場變得 更加寬廣與有競爭力。 [0004] 高亮度LED的特點就是流過LED陽極和陰極的電流特別大 ’在在達到數安培，傳統的LEE):投影機控制技術，對led 的陽極電壓通常採用定電壓模式。但由於每顆led所消耗 的電壓都不一樣，而且隨LED溫度、流過的電流、單體差 異不同而不同，因此在固定電愿模式下，部分需要較低 電壓的LED浪費更多的功率，而部分需要較高電壓的LE]) 可能無法正常工作，直接造成的後果就是投影機的功率 和亮度偏差較大。 【發明内容】 [0005] 有鑑於此，有必要提供一種能改變控制電壓的[ED控制電 路。 098122158 表單編號A0101 第5買/共18頁 0982037623-0 201101918 [0006] [0007] [0008] [0009] 098122158 二種led控制電路，其包括—電流及脈衝控制模組、—第 -屋控電阻、H控制模組、 銪供、汉電壓調 丄1、、、、且；所述電流及脈衝控制模組包括用於接收一微控 信號的第-輪入端、用於接收一電壓控制信號的第二： 入端'與地相連接的第三輸入端及一輸出端;所述第二 麼控電阻包括與LED陰極相連接的輪入端、與電流及脈衝 控制k組的第三輸人端和輸出端分別連接的輸出端及控 制端；所述電壓㈣肋包括驗接㈣賴控信_ 第一輪入端、與led陰極相連接的第二輸入端及—輸出端 ，所述回饋模組包括與LED陽極相連接的第一輪入端與 電屋控制模組的輸出端相連接的第二輸A端及一輸出端 ，所述電壓調節模組包括與—電源電壓相連接的第一輸 入端與回饋模組的輸出端相連接的第二輸入端及與led 陽極相連接的輸出端。 與先％技術相比較，所述LED控制電路通過控制第一壓控 電阻的電阻值從而使流經LED的正向電流保持相對穩定； 所述书壓控制模組根據LED的陰極電壓調節其陽極電壓， 使陽極電壓根據LED的陽極與陰極之間的正向電壓變化而 變化，從而提高LED對電源的利用效率。 【實施方式】 下面將結合附圖與實施例對本技術方案之LEJ)控制電路作 進一步詳細說明。 叫參閱圖1及圖2，其為本發明實施方式的LED控制電路 100，其用於控制一個LED的發光。所述LED具有一正向 電壓和—正向電流，所述正向電壓為LED工作時LED的陽 表單編號A0101 第6頁/共18頁 0982037623-0 201101918 [0010] [0011] ο [0012] ❹ 極與陰極之間所需消耗的壓降，所述正向電流為LED工作 時流經LED的陽極和陰極的電流。 所述LED控制電路1〇〇包括—電流及脈衝控制模組1〇、一 第一壓控電阻Q1、一電壓控制模組2〇、一回饋模組3〇、 一電壓調節模組4 0及一分壓電阻rv。 所述電流及脈衝控制模組1〇包括一第一輸入端Η、一第 二輸入端12、一第三輸入端13及一輸出端14。所述第一 輸入端11用於接收一微控信號，所述第二輸入端12用於 接收一電廢控制信號，所述第三輸入端13接收流經led的 回饋電流。所述微控信號用於控制LED的開關；所述電壓 控制信號根據流經L E D的回饋電流從輸出端14輸出一控制 電壓。 所述第一壓控電阻Q1包括一輸入端D1、一輸出端S1及一 控制端G1 ;所述輸入端D1與LED的陰極相連接，所述輸出 端S1與所述電流及脈衝控制模組1〇的第三輸入端丨3相連 接並接地，所述控制端G1與所述電流及脈衝控制模組j 〇 的輸出端14相連接。所述第一壓控電阻Q1根據控制端G1 所接收的控制電壓調整輸入端D1與輸出端S1之間的電阻 值，從而使流經LED的正向電流保持一相對穩定的狀態。 本實施方式中，所述第一壓控電阻Q1為一N-MOS型電晶體 ;所述輸入端D1為漏極，所述輸出端S1為源極，所述控 制端G1為拇極。 所述電壓控制模組20包括一第一輸入端21、一第二輸入 端22及一輸出端23 ;所述第一輸入端21用於接收所述微 098122158 表單編號A0101 第7頁/共18頁 0982037623-0 [0013] 201101918 控信號，所述第二輸入端22與LED的陰極相連接《所述電 壓控制模組20包括一類比開關Q2、一晶片U1、一第一電 容C1、一第二電容C2、一第一電阻R1、一第二電阻R2、 一第三電阻R3、一第四電阻R4、一第五電阻R5、一第六 電阻R6、一第七電阻R7及一第八電阻R8。所述類比開關 Q2包括一輸入端D2、一輸出端S2及一控制端G2，所述控 制端G2用於控制所述輸入端D2與輸出端S2的開啟與閉合 。本實施方式中，所述類比開關Q2為一 N-M0S電晶體，所 述輸入端D2為漏極，所述輸出端S2為源極，所述控制端 G2為栅極。所述晶片.U.1具有放大器和積分運算的雙操作 功能，所述晶片U1型號為UM 6 0 3，所述晶片u 1具有8個引 腳’第一引腳為第一輸出端、第二引腳為第一反向輸入 端、第三引腳為第一輸入端 '第四引腳為負極、第五引 腳為第一輸入端 '苐六引腳為苐二反向輸入端、第七引 腳為第二輸出端、第八引腳為正極。 [0014] 所述類比開關Q2的輸入端D2與LED的陰極相連接。所述第 一電阻R1的第一端用於接收微控信號，第二端與類比開 關Q2的控制端G2相連接。所述第二電阻R2的第一端與％ 比開關Q2的輸出端S2相連接。所述第—電容'c 1的第端 第二電阻R2的第二端相連接。所述第三電阻以的第—端 與第-電容ci的第-端相連接，第三電阻R3的第二端與 第一電容C1的第二端相連接。所述第四電阻^的第—端 與第-電容(：1的第二端相連接並接地，第二端與類比開 關Q2的控制端G2相連接。所述晶片w的第八引腳接—正 電壓，第四引腳接地，第五引腳與第三電阻_第—端 098122158 表單編號A0101 第8頁/共18頁 0982037623-0 201101918 相連接。所述第五電阻R5的第一端與晶片U1的第六引腳 相連接，第二端接地。所述第六電阻以的第—端與第五 電阻R5的第一端相連接，第六電阻R6的第二蠕與晶片 的第七引腳相連接。所述第七電阻以的第一端與晶片 的第七引腳相連接，第二端與晶片“的第二弓丨腳相連接 。所述第八電阻以的第一端與晶片耵的第三引腳相連接 ，第二端與U1的第八引腳相連接。所述第二電容以的第 Ο201101918 VI. Description of the Invention: [Technical Field] [0001] The present invention relates to a control technique, and more particularly to an LED control circuit applied to a projector. [Prior Art] [0002] LED has the advantages of low power consumption, long life, small size, and high light utilization efficiency. With the development of technology, it has become a reality that LEDs have replaced traditional lighting bulbs and applied in various fields. 0 [0003] LED applications in the field of projectors are due to the development of high-brightness LED technology; since LEDs have a lifetime of up to 100,000 hours, they are about 3,000 hours longer than traditional halogen bulbs or high-pressure mercury bulbs. Its advantages are very obvious. Led makes the projection of the life # greatly improved, so the factors that previously restricted the development of the projector have been solved, making the projector market more broad and competitive. [0004] The characteristics of high-brightness LEDs are that the current flowing through the anode and cathode of the LED is particularly large. In the case of several amps, the conventional LEE: projector control technology, the anode voltage of the LED is usually in a constant voltage mode. However, since the voltage consumed by each LED is different, and it varies with LED temperature, current flowing, and monomer variation, some LEDs that require lower voltage waste more power in the fixed power mode. However, some LEs that require a higher voltage may not work properly, and the direct result is that the power and brightness deviation of the projector is large. SUMMARY OF THE INVENTION [0005] In view of the above, it is necessary to provide an [ED control circuit capable of changing a control voltage. 098122158 Form No. A0101 No. 5 Buy/Total 18 Page 0982037623-0 201101918 [0006] [0007] [0008] [0009] 098122158 Two kinds of led control circuits, including - current and pulse control module, - first house control resistor , H control module, 铕 supply, 电压 voltage 丄 1, , , and; the current and pulse control module includes a first wheel input for receiving a micro control signal for receiving a voltage control signal The second: the input end is connected to the ground and the third input end and an output end; the second control resistor includes a wheeled end connected to the LED cathode, and a third input of the current and pulse control k group The output end and the control end respectively connected to the human end and the output end; the voltage (four) rib includes a connection (4) control signal _ a first round-in end, a second input end connected to the LED cathode, and an output end, The feedback module includes a second input end connected to the LED anode and a second output A end and an output end connected to the output end of the electric house control module, and the voltage regulating module includes a connection with the power supply voltage. a second input of the first input coupled to the output of the feedback module An output terminal and an anode connected to the led. Compared with the first % technology, the LED control circuit keeps the forward current flowing through the LED relatively stable by controlling the resistance value of the first voltage control resistor; the book pressure control module adjusts the anode according to the cathode voltage of the LED The voltage causes the anode voltage to change according to the forward voltage change between the anode and the cathode of the LED, thereby improving the utilization efficiency of the LED for the power source. [Embodiment] The LEJ) control circuit of the present technical solution will be further described in detail below with reference to the accompanying drawings and embodiments. Referring to Figures 1 and 2, an LED control circuit 100 for controlling the illumination of an LED is shown in the present invention. The LED has a forward voltage and a forward current, and the forward voltage is a positive form number of the LED when the LED is operating. A0101 Page 6 of 18 pages 0982037623-0 201101918 [0011] [0012] The voltage drop required between the anode and the cathode, which is the current flowing through the anode and cathode of the LED during operation of the LED. The LED control circuit 1 includes a current and pulse control module 1 , a first voltage control resistor Q1 , a voltage control module 2 , a feedback module 3 , a voltage regulation module 40 , and A voltage divider resistor rv. The current and pulse control module 1 includes a first input port, a second input terminal 12, a third input terminal 13 and an output terminal 14. The first input terminal 11 is configured to receive a micro control signal, the second input terminal 12 is configured to receive an electrical waste control signal, and the third input terminal 13 receives a feedback current flowing through the LED. The micro control signal is used to control a switch of the LED; the voltage control signal outputs a control voltage from the output terminal 14 according to a feedback current flowing through the L E D . The first voltage-controlled resistor Q1 includes an input terminal D1, an output terminal S1, and a control terminal G1. The input terminal D1 is connected to the cathode of the LED, and the output terminal S1 and the current and pulse control module are The third input terminal 丨3 of one turn is connected and grounded, and the control terminal G1 is connected to the output terminal 14 of the current and pulse control module j 。 . The first voltage-controlled resistor Q1 adjusts the resistance value between the input terminal D1 and the output terminal S1 according to the control voltage received by the control terminal G1, so that the forward current flowing through the LED maintains a relatively stable state. In this embodiment, the first voltage-controlled resistor Q1 is an N-MOS type transistor; the input terminal D1 is a drain, the output terminal S1 is a source, and the control terminal G1 is a thumb pole. The voltage control module 20 includes a first input terminal 21, a second input terminal 22, and an output terminal 23; the first input terminal 21 is configured to receive the micro 098122158 Form No. A0101 Page 7 of 18 Page 0982037623-0 [0013] 201101918 control signal, the second input terminal 22 is connected to the cathode of the LED. The voltage control module 20 includes an analog switch Q2, a chip U1, a first capacitor C1, a first Two capacitors C2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7 and an eighth resistor R8. The analog switch Q2 includes an input terminal D2, an output terminal S2, and a control terminal G2. The control terminal G2 is configured to control the opening and closing of the input terminal D2 and the output terminal S2. In this embodiment, the analog switch Q2 is an N-MOS transistor, the input terminal D2 is a drain, the output terminal S2 is a source, and the control terminal G2 is a gate. The wafer.U.1 has a dual operation function of an amplifier and an integral operation, the wafer U1 model is UM 630, and the wafer u 1 has 8 pins 'the first pin is the first output terminal, the first The second pin is the first inverting input terminal, the third pin is the first input end, the fourth pin is the negative terminal, the fifth pin is the first input terminal, and the sixth pin is the second inverting input terminal. The seventh pin is the second output terminal, and the eighth pin is the positive electrode. [0014] The input terminal D2 of the analog switch Q2 is connected to the cathode of the LED. The first end of the first resistor R1 is for receiving a micro control signal, and the second end is connected to the control terminal G2 of the analog switch Q2. The first end of the second resistor R2 is connected to the output terminal S2 of the % switch Q2. The first end of the first capacitor 'c 1 is connected to the second end of the second resistor R2. The third end of the third resistor is connected to the first end of the first capacitor ci, and the second end of the third resistor R3 is connected to the second end of the first capacitor C1. The first end of the fourth resistor is connected to the second capacitor of the first capacitor and is grounded, and the second terminal is connected to the control terminal G2 of the analog switch Q2. The eighth pin of the wafer w is connected. - positive voltage, fourth pin grounded, fifth pin and third resistor _ first terminal 098122158 form number A0101 page 8 / total 18 page 0982037623-0 201101918 connected. The first end of the fifth resistor R5 Connected to the sixth pin of the wafer U1, the second end is grounded. The sixth end of the sixth resistor is connected to the first end of the fifth resistor R5, and the second end of the sixth resistor R6 is the first of the wafer. The seventh pin is connected. The seventh end is connected to the seventh pin of the wafer, and the second end is connected to the second leg of the wafer. The first resistor is first. The terminal is connected to the third pin of the chip, and the second end is connected to the eighth pin of U1.
端與晶片U1的第二引腳相連接，第二端與晶片W的第 一引腳相連接。 剛料回饋模組30包括一第—輸入端31、一第二輸入端32 及一輸出端33 ;所述第-輸入端”與⑽的陽極相連接， 所述第二輪入端32與電壓控制模組20的輸出端23相連接 所述回饋模組3〇包括一第二壓控電阻、—第九電阻 R9、—第十電阻R10及一第十—電&R11。所述第二壓控 電阻Q3包括一輸入端D3、一輸出端幻及一控制端^，所 述2制端G 3用於控制所述輸入端D 3與輸出㈣的開啟與 二。本實施方式中，所述第二壓控電阻Q3為一N—M〇s電 a體所述輸入端D3為漏極，所述輸出端S3為源極，所 ，控制端G3為栅極。所述第二M控電阻⑽的控制端^與 曰曰片U1的第一引腳相連接，所述輸出端幻接地。所述第 。R9的第—端與第二壓控電阻的輪人端⑽相連接 H與電壓調節模組卿連接。所述第十電阻R10的 第端與第二壓控電阻Q3的輸出端83相連接，第十電阻 R10的第二端與第九電阻R9的第二端相連接。所述第十一 電阻im的第一端分別與第十電阻Ri〇的第二端和第九電 098122158 表單編號A0101 第9頁/共18頁 0982037623-0 201101918 阻R9的第—端相連接，所述第十一電阻们1的第一端與 LED的陽極相連接。 [0016]所述電壓調節模組40包括一第一輸入端41、第二輸入端 42及一輸出端43 ;所述第一輸入端41用於接收一電源電 壓；所述第二輸入端42與回饋模組30的輸出端33相連接 ，即與第九電阻R 9的第二端相連接；所述電壓調節模組 40的輸出端43與LED的陽極相連接。 [0017]所述分壓電阻RV的第一端連接於電流及脈衝控制模組i 〇 的第三輸入端13和第一壓控電阻qi的輸出端81之間，其 第一端接地。流經分壓電阻RV的..電流在分壓電阻rv第一 端形成一電壓。 [0018] 098122158The terminal is connected to the second pin of the wafer U1, and the second terminal is connected to the first pin of the wafer W. The rigid material feedback module 30 includes a first input terminal 31, a second input terminal 32 and an output terminal 33; the first input terminal is connected to the anode of the (10), and the second wheel terminal 32 is connected to the voltage. The output terminal 23 of the control module 20 is connected to the feedback module 3, and includes a second voltage-controlled resistor, a ninth resistor R9, a tenth resistor R10, and a tenth-electric & R11. The voltage control resistor Q3 includes an input terminal D3, an output terminal and a control terminal, and the 2 terminal G3 is used to control the opening and the output of the input terminal D3 and the output (4). In this embodiment, the The second voltage-controlled resistor Q3 is an N-M〇s electric a body, the input terminal D3 is a drain, the output terminal S3 is a source, and the control terminal G3 is a gate. The second M-control The control terminal of the resistor (10) is connected to the first pin of the die U1, and the output terminal is grounded. The first end of the first R9 is connected to the wheel terminal (10) of the second voltage controlled resistor. The voltage regulating module is connected. The first end of the tenth resistor R10 is connected to the output end 83 of the second voltage control resistor Q3, and the second end of the tenth resistor R10 and the second end of the ninth resistor R9 The first end of the eleventh resistor im is respectively connected with the second end of the tenth resistor Ri 和 and the ninth electric 098122158 Form No. A0101 Page 9 / 18 pages 0982037623-0 201101918 The end of the resistor R9 The first end of the eleventh resistor 1 is connected to the anode of the LED. [0016] The voltage regulating module 40 includes a first input end 41, a second input end 42 and an output end 43. The first input end 41 is configured to receive a power supply voltage; the second input end 42 is coupled to the output end 33 of the feedback module 30, that is, to the second end of the ninth resistor R9; The output end 43 of the voltage regulating module 40 is connected to the anode of the LED. [0017] The first end of the voltage dividing resistor RV is connected to the third input terminal 13 of the current and pulse control module i 和 and the first voltage control Between the output terminals 81 of the resistors qi, the first end thereof is grounded. The current flowing through the voltage dividing resistor RV forms a voltage at the first end of the voltage dividing resistor rv. [0018] 098122158
在使用過程中，所述電流及脈衝控制模組1〇根據所述微 控h號控制LED的開關。該電流及脈衝控制模組1〇採集分 壓電阻RV第一端的電壓，並根據所述電壓及所述分壓電 阻RV阻值得到LED的工作電流，將該工作電流與led的額 定電流進行比較，所述電流及脈衝控制模組1〇根據從該 龟流及脈衝控制模組1 〇的第二輸入端12輸入的電壓控制 信號及比較結果對第一壓控電阻q丨的控制端G丨產生一控 制電壓。所述控制電壓用於控制第一壓控電阻Q1的輸入 端D1與輸出端S1之間的電阻值大小，從而實現對流過LED 的正向電流的調節。所述電壓控制模組2〇根據微控信號 的控制採集LED的陰極電壓，由於所述LED的陰極電壓等 於其陽極電壓減去其正向電壓，所述陰極電壓越小代表 LED的陽極電壓得到了最大化使用；為了保證有電流從第 一壓控電阻Q1中流過’且根據LED的相關參數，設定LEE) 表單編號腳1 ? 10頁/共18頁 0982037623-0 201101918 Ο 的陰極參考電壓為〇·3ν。該電壓控龍組㈣第二輸入 細>22接收所述微控彳§號控制所述類比開關的的開啟；當 類比開關Q2開啟時，LED陰極電壓從晶_的第五引腳進 入，經過晶片U1放大後的LED陰極電壓從第七引腳輸出； 從第七弓丨腳輸出的信號再進入第二引腳，經過晶片Μ的 積分運算後’從第一引腳輸出一斜率線性信號。所述第 二壓控電阻Q3的控制端G3接收斜率線性信號，在所述斜 率線性信號的作用下，使得第二壓控電峰的輪入端！)3 與輸出端S3之間的電阻值發生改變，以調節回饋模組 輸出端42所輸出的陽極回饋電壓的大小。所述電壓調節 模組40根據陽極回饋電壓調節輸出端43輸出的陽極電壓 ’從而實現對LED陽極電壓的控制。 [0019] 與先前技術相比較，所述LED控制電路通過控制第一壓栌 電阻的電阻值從而使流經L E D的正向電流保持相對穩定； 所述電壓控制模組根據LED的陰極電壓調節其陽極電壓， ❹ [0020] 使陽極電壓與LED的正向電壓的鍵化一鼓，從而提言 對電源的利用效率》 门 综上所述，本發明確已符合發明專利之要件，遂依法提 出專利申請。，准，以上所述者僅為本發明之較佳實施方 式，自不能以此限制本案之申請專利範圍。舉凡熟乘本 案技藝之人士援依本發明之精神所作之等欵修飾或變化 ，皆應涵蓋於以下申請專利範圍内。 【圖式簡單說明】 圖1係本發明實施方式提供的LED控制電路的功能模組示 意圖。 098122158 表單編號A0101 第11頁/共18頁 0982037623-0 [0021] 201101918 [0022] 圖2係圖1中的LED控制電路的電壓控制模組與回饋模組的 電路圖。 【主要元件符號說明】 [0023] LED控制電路 100 電流及脈衝控 10 制模組 第一輸入端 11 第二輸入端 12 第三輸入端 13 輸出端 14 電壓控制模組 20 第一輸入端 21 第二輸入端 22 輸出端 23 回饋模組 30 第一輸入端 31 第二輸入端 32 輸出端 33 電壓調節模組 40 第一輸入端 41 第二輸入端 42 輸出端 43 第一壓控電阻 Q1 輸入端 D1 輸出端 S1 控制端 G1 分壓電阻 RV 類比開關 Q2 輸入端 D2 輸出端 S2 控制端 G2 晶片 U1 第一電容 C1 第二電容 C2 第一電阻 R1 第二電阻 R2 第三電阻 R3 第四電阻 R4 第五電阻 R5 第六電阻 R6 第七電阻 R7 第八電阻 R8 第二壓控電阻 Q3 輸入端 D3 輸出端 S3 控制端 G3 第九電阻 R9 第十電阻 R10 表單編號A0101 第12頁/共18頁 0982037623-0 098122158 201101918 一____ I第十一電阻 R11 Ο ❹ 098122158 表單編號A0101 第13頁/共18頁 0982037623-0During use, the current and pulse control module 1 controls the switching of the LEDs according to the micro control h number. The current and pulse control module 1 〇 collects the voltage of the first end of the voltage dividing resistor RV, and obtains the working current of the LED according to the voltage and the resistance value of the voltage dividing resistor RV, and performs the working current with the rated current of the LED. Comparing, the current and pulse control module 1 控制 is based on the voltage control signal input from the second input terminal 12 of the turtle flow and pulse control module 1 及 and the comparison result to the control terminal G of the first voltage control resistor q 丨丨 generates a control voltage. The control voltage is used to control the magnitude of the resistance between the input terminal D1 and the output terminal S1 of the first voltage-controlled resistor Q1, thereby achieving adjustment of the forward current flowing through the LED. The voltage control module 2 采集 collects the cathode voltage of the LED according to the control of the micro control signal. Since the cathode voltage of the LED is equal to its anode voltage minus its forward voltage, the smaller the cathode voltage is, the anode voltage of the LED is obtained. Maximize the use; in order to ensure that there is current flowing through the first voltage-controlled resistor Q1' and set the LEE according to the relevant parameters of the LED) Form number foot 1 ? 10 pages / total 18 pages 0982037623-0 201101918 Ο The cathode reference voltage is 〇·3ν. The voltage control group (4) second input fine > 22 receives the micro control 彳 § number to control the opening of the analog switch; when the analog switch Q2 is turned on, the LED cathode voltage enters from the fifth pin of the crystal _ The LED cathode voltage amplified by the chip U1 is output from the seventh pin; the signal output from the seventh bow pin enters the second pin, and after the integration operation of the chip ', a slope linear signal is output from the first pin. . The control terminal G3 of the second voltage-controlled resistor Q3 receives a slope linear signal, and under the action of the slope linear signal, the wheel-in terminal of the second voltage-controlled electric peak is made! The resistance value between the 3 and the output terminal S3 is changed to adjust the magnitude of the anode feedback voltage outputted by the feedback module output terminal 42. The voltage regulating module 40 adjusts the anode voltage of the output terminal 43 according to the anode feedback voltage to achieve control of the anode voltage of the LED. [0019] Compared with the prior art, the LED control circuit keeps the forward current flowing through the LED relatively stable by controlling the resistance value of the first voltage resistor; the voltage control module adjusts the cathode voltage according to the LED Anode voltage, ❹ [0020] The anode voltage is polarized with the forward voltage of the LED, thereby promoting the utilization efficiency of the power supply. As described above, the present invention has indeed met the requirements of the invention patent, and patented according to law. Application. The above is only the preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application in this case. Any modification or variation made by a person skilled in the art will be covered by the following claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a functional module of an LED control circuit according to an embodiment of the present invention. 098122158 Form No. A0101 Page 11 of 18 0982037623-0 [0021] FIG. 2 is a circuit diagram of a voltage control module and a feedback module of the LED control circuit of FIG. [Main component symbol description] [0023] LED control circuit 100 current and pulse control 10 system module first input terminal 11 second input terminal 12 third input terminal 13 output terminal 14 voltage control module 20 first input terminal 21 Two input terminal 22 output terminal 23 feedback module 30 first input terminal 31 second input terminal 32 output terminal 33 voltage regulation module 40 first input terminal 41 second input terminal 42 output terminal 43 first voltage control resistor Q1 input terminal D1 output terminal S1 control terminal G1 voltage dividing resistor RV analog switch Q2 input terminal D2 output terminal S2 control terminal G2 wafer U1 first capacitor C1 second capacitor C2 first resistor R1 second resistor R2 third resistor R3 fourth resistor R4 Five resistor R5 Sixth resistor R6 Seventh resistor R7 Eight resistor R8 Second voltage control resistor Q3 Input terminal D3 Output terminal S3 Control terminal G3 Ninth resistor R9 Tenth resistor R10 Form number A0101 Page 12 of 18 0982037623- 0 098122158 201101918 一 ____ I eleventh resistor R11 Ο 098 098122158 Form No. A0101 Page 13 of 18 0982037623-0