TWM503054U - Light adjusting circuit - Google Patents

Description

調光電路Dimming circuit

本新型是有關於調光技術，特別是指一種調光電路。The present invention relates to dimming technology, and more particularly to a dimming circuit.

發光二極體(LED)驅動電路能根據調光電壓的幅值來調整流過發光二極體的電流的幅值，以改變發光二極體的發光亮度。因此，如何供應幅值變動範圍能達到預設電壓範圍的調光電壓，以使發光二極體的發光亮度的變動範圍達到預設亮度範圍，是一個重要的課題。The light emitting diode (LED) driving circuit can adjust the amplitude of the current flowing through the light emitting diode according to the magnitude of the dimming voltage to change the light emitting brightness of the light emitting diode. Therefore, how to supply a dimming voltage whose amplitude variation range can reach a preset voltage range is such that the variation range of the luminance of the light emitting diode reaches a preset luminance range is an important subject.

因此，本新型之目的即在提供一種調光電路，可以供應一個電壓，該電壓的幅值變動範圍能達到一個預設電壓範圍。Therefore, the purpose of the present invention is to provide a dimming circuit that can supply a voltage whose amplitude varies over a predetermined voltage range.

於是，本新型調光電路包含一個調光輸入端、一個調光輸出端、一個放大器、一個電阻及一個齊納二極體。該放大器具有一個電連接到該調光輸入端的非反相輸入端、一個電連接到該調光輸出端的反相輸入端，及一個輸出端。該電阻電連接在該放大器的輸出端與該調光輸出端之間。該齊納二極體具有一個接地的陽極，及一個電連 接到該調光輸出端的陰極。Thus, the novel dimming circuit includes a dimming input, a dimming output, an amplifier, a resistor, and a Zener diode. The amplifier has a non-inverting input electrically coupled to the dimming input, an inverting input electrically coupled to the dimming output, and an output. The resistor is electrically coupled between the output of the amplifier and the dimming output. The Zener diode has a grounded anode and an electrical connection Connected to the cathode of the dimming output.

本新型之功效在於：藉由將該齊納二極體電連接到該調光輸出端，且藉由利用該電阻來控制流過該齊納二極體的電流的幅值，可以使該調光輸出端上的電壓的幅值變動範圍能達到一個預設電壓範圍。The effect of the novel is to make the adjustment by electrically connecting the Zener diode to the dimming output and by controlling the magnitude of the current flowing through the Zener diode by using the resistor. The amplitude of the voltage at the light output can vary over a predetermined voltage range.

11‧‧‧調光輸入端11‧‧‧ dimming input

12‧‧‧調光輸出端12‧‧‧ dimming output

13‧‧‧第一放大器13‧‧‧First amplifier

14‧‧‧第一電阻14‧‧‧First resistance

15‧‧‧二極體15‧‧‧ diode

16‧‧‧齊納二極體16‧‧‧Zina diode

17‧‧‧電容17‧‧‧ Capacitance

18‧‧‧第二電阻18‧‧‧second resistance

19‧‧‧電流源19‧‧‧current source

191‧‧‧第二放大器191‧‧‧second amplifier

192‧‧‧第三電阻192‧‧‧ third resistor

193‧‧‧第四電阻193‧‧‧fourth resistor

194‧‧‧第五電阻194‧‧‧ fifth resistor

195‧‧‧第六電阻195‧‧‧ sixth resistor

196‧‧‧第七電阻196‧‧‧ seventh resistor

本新型之其他的特徵及功效，將於參照圖式的實施方式中清楚地呈現，其中：圖1是一個示意電路圖，說明本新型調光電路的實施例。Other features and effects of the present invention will be apparent from the following description of the drawings. FIG. 1 is a schematic circuit diagram illustrating an embodiment of the novel dimming circuit.

參閱圖1，本新型調光電路的實施例包含一個調光輸入端11、一個調光輸出端12、一個第一放大器13、一個第一電阻14、一個二極體15、一個齊納二極體16、一個電容17、一個第二電阻18及一個電流源19。Referring to FIG. 1, an embodiment of the novel dimming circuit includes a dimming input terminal 11, a dimming output terminal 12, a first amplifier 13, a first resistor 14, a diode 15, and a Zener diode. Body 16, a capacitor 17, a second resistor 18 and a current source 19.

第一放大器13具有一個電連接到調光輸入端11的非反相輸入端、一個電連接到調光輸出端12的反相輸入端，及一個輸出端。The first amplifier 13 has a non-inverting input electrically coupled to the dimming input terminal 11, an inverting input electrically coupled to the dimming output terminal 12, and an output.

第一電阻14及二極體15在第一放大器13的輸出端與調光輸出端12之間串聯。在本實施例中，第一電阻14具有一個電連接到第一放大器13之輸出端的第一端，及一個第二端，二極體15具有一個電連接到第一電阻14之第二端的陽極，及一個電連接到調光輸出端12的陰極。 但是，在其它實施例中，第一電阻14及二極體15的串聯順序可以互換，也就是二極體15的陽極電連接到第一放大器13之輸出端，第一電阻14電連接在二極體15的陰極與調光輸出端12之間。The first resistor 14 and the diode 15 are connected in series between the output of the first amplifier 13 and the dimming output terminal 12. In the present embodiment, the first resistor 14 has a first end electrically connected to the output end of the first amplifier 13, and a second end, the diode 15 has an anode electrically connected to the second end of the first resistor 14. And a cathode electrically connected to the dimming output terminal 12. However, in other embodiments, the series order of the first resistor 14 and the diode 15 may be interchanged, that is, the anode of the diode 15 is electrically connected to the output end of the first amplifier 13, and the first resistor 14 is electrically connected to the second. The cathode of the pole body 15 is between the dimming output terminal 12.

該齊納二極體16具有一個接地的陽極，及一個電連接到調光輸出端12的陰極。The Zener diode 16 has a grounded anode and a cathode electrically coupled to the dimming output terminal 12.

電容17電連接在調光輸入端11與地之間。Capacitor 17 is electrically coupled between dimming input terminal 11 and ground.

第二電阻18電連接在第一放大器13的輸出端與地之間。The second resistor 18 is electrically connected between the output of the first amplifier 13 and ground.

電流源19電連接到調光輸入端11，且供應一個參考電流Iref到調光輸入端11。在本實施例中，電流源19包括一個第二放大器191、一個第三電阻192、一個第四電阻193、一個第五電阻194、一個第六電阻195及一個第七電阻196。第二放大器191具有一個非反相輸入端、一個反相輸入端及一個輸出端。第三電阻192電連接在第二放大器191的反相輸入端與地之間。第四電阻193具有一個電連接到第二放大器191之非反相輸入端的第一端，及一個接收一個參考電壓Vref的第二端。第五電阻194電連接在第二放大器191的反相輸入端與調光輸入端11之間。第六電阻195電連接在第二放大器191的非反相輸入端與輸出端之間。第七電阻196電連接在第二放大器191的輸出端與調光輸入端11之間。參考電流Iref的幅值取決於參考電壓Vref的幅值及第三至第七電阻192~196的阻值。The current source 19 is electrically connected to the dimming input terminal 11 and supplies a reference current Iref to the dimming input terminal 11. In the present embodiment, the current source 19 includes a second amplifier 191, a third resistor 192, a fourth resistor 193, a fifth resistor 194, a sixth resistor 195, and a seventh resistor 196. The second amplifier 191 has a non-inverting input, an inverting input, and an output. The third resistor 192 is electrically coupled between the inverting input of the second amplifier 191 and ground. The fourth resistor 193 has a first terminal electrically coupled to the non-inverting input of the second amplifier 191, and a second terminal receiving a reference voltage Vref. The fifth resistor 194 is electrically connected between the inverting input terminal of the second amplifier 191 and the dimming input terminal 11. The sixth resistor 195 is electrically connected between the non-inverting input terminal and the output terminal of the second amplifier 191. The seventh resistor 196 is electrically connected between the output of the second amplifier 191 and the dimming input terminal 11. The magnitude of the reference current Iref depends on the magnitude of the reference voltage Vref and the resistance values of the third to seventh resistors 192-196.

在本實施例中，調光輸入端11適用於電連接到一個外部電阻(圖未示)，或電連接到一個外部電壓源(圖未示)以從外部電壓源接收一個輸入電壓。當調光輸入端11電連接到外部電阻時，電流源19所供應的參考電流Iref會流過外部電阻，使得調光輸入端11上的電壓的幅值等於參考電流Iref的幅值與外部電阻的阻值之乘積。當調光輸入端11電連接到外部電壓源時，調光輸入端11上的電壓的幅值等於外部電壓源所供應的輸入電壓的幅值。In this embodiment, the dimming input terminal 11 is adapted to be electrically connected to an external resistor (not shown) or to an external voltage source (not shown) to receive an input voltage from an external voltage source. When the dimming input terminal 11 is electrically connected to the external resistor, the reference current Iref supplied from the current source 19 flows through the external resistor, so that the magnitude of the voltage on the dimming input terminal 11 is equal to the magnitude of the reference current Iref and the external resistor. The product of the resistance. When the dimming input 11 is electrically coupled to an external voltage source, the magnitude of the voltage across the dimming input 11 is equal to the magnitude of the input voltage supplied by the external voltage source.

在本實施例中，第一放大器13、第一電阻14及二極體15共同構成一個緩衝器，且流過齊納二極體16的電流的幅值會受第一電阻14的阻值影響。因此，可以相當容易地將第一電阻14的阻值選取為足以讓齊納二極體16在做動時所流過的電流的幅值能達到齊納二極體16的規格書所載的測試電流值，使得齊納二極體16在做動時的跨壓的幅值能達到齊納二極體16的規格書所載的崩潰電壓值。如此一來，當調光輸入端11上的電壓的幅值小於齊納二極體16的崩潰電壓值時，調光輸出端12上的電壓的幅值等於調光輸入端11上的電壓的幅值，而當調光輸入端11上的電壓的幅值大於齊納二極體16的崩潰電壓值時，調光輸出端12上的電壓的幅值會被齊納二極體16箝制在其崩潰電壓值。In this embodiment, the first amplifier 13, the first resistor 14, and the diode 15 together form a buffer, and the magnitude of the current flowing through the Zener diode 16 is affected by the resistance of the first resistor 14. . Therefore, the resistance of the first resistor 14 can be relatively easily selected to be sufficient for the magnitude of the current flowing by the Zener diode 16 during operation to be in the specification of the Zener diode 16. The current value is tested such that the magnitude of the voltage across the Zener diode 16 during actuation can reach the breakdown voltage value contained in the specification of the Zener diode 16. In this way, when the magnitude of the voltage on the dimming input terminal 11 is less than the breakdown voltage value of the Zener diode 16, the magnitude of the voltage on the dimming output terminal 12 is equal to the voltage on the dimming input terminal 11. Amplitude, and when the magnitude of the voltage on the dimming input terminal 11 is greater than the breakdown voltage value of the Zener diode 16, the magnitude of the voltage across the dimming output terminal 12 is clamped by the Zener diode 16 Its crash voltage value.

值得注意的是，在其它實施例中，可以對本實施例做出以下修改：It should be noted that in other embodiments, the following modifications may be made to the embodiment:

1.電容17可以被省略。1. Capacitor 17 can be omitted.

2.第二電阻18可以被省略。2. The second resistor 18 can be omitted.

3.當調光輸入端11只適用於電連接到外部電壓源時，電流源19可以被省略。3. When the dimming input 11 is only suitable for electrical connection to an external voltage source, the current source 19 can be omitted.

4.二極體15可以被省略。此時，第一電阻14電連接在第一放大器13的輸出端與調光輸出端12之間。4. The diode 15 can be omitted. At this time, the first resistor 14 is electrically connected between the output end of the first amplifier 13 and the dimming output terminal 12.

綜上所述，本實施例藉由將齊納二極體16電連接到調光輸出端12，且藉由利用第一電阻14來控制流過齊納二極體16的電流的幅值，可以使調光輸出端16上的電壓的幅值變動範圍能達到一個預設電壓範圍(例如0到齊納二極體16的崩潰電壓值)。所以本實施例確實能達成本新型之目的。In summary, the present embodiment electrically connects the Zener diode 16 to the dimming output terminal 12, and controls the magnitude of the current flowing through the Zener diode 16 by using the first resistor 14. The magnitude of the voltage across the dimming output 16 can be varied to a predetermined voltage range (eg, 0 to the breakdown voltage value of the Zener diode 16). Therefore, this embodiment can achieve the object of the present invention.

惟以上所述者，僅為本新型之實施例而已，當不能以此限定本新型實施之範圍，即大凡依本新型申請專利範圍及專利說明書內容所作之簡單的等效變化與修飾，皆仍屬本新型專利涵蓋之範圍內。However, the above description is only for the embodiments of the present invention, and the scope of the present invention cannot be limited thereto, that is, the simple equivalent changes and modifications made by the present patent application scope and the contents of the patent specification are still It is within the scope of this new patent.

11‧‧‧調光輸入端11‧‧‧ dimming input

12‧‧‧調光輸出端12‧‧‧ dimming output

13‧‧‧第一放大器13‧‧‧First amplifier

14‧‧‧第一電阻14‧‧‧First resistance

15‧‧‧二極體15‧‧‧ diode

16‧‧‧齊納二極體16‧‧‧Zina diode

17‧‧‧電容17‧‧‧ Capacitance

18‧‧‧第二電阻18‧‧‧second resistance

19‧‧‧電流源19‧‧‧current source

191‧‧‧第二放大器191‧‧‧second amplifier

192‧‧‧第三電阻192‧‧‧ third resistor

193‧‧‧第四電阻193‧‧‧fourth resistor

194‧‧‧第五電阻194‧‧‧ fifth resistor

195‧‧‧第六電阻195‧‧‧ sixth resistor

196‧‧‧第七電阻196‧‧‧ seventh resistor

Claims (7)

一種調光電路，包含：一個調光輸入端；一個調光輸出端；一個第一放大器，具有一個電連接到該調光輸入端的非反相輸入端、一個電連接到該調光輸出端的反相輸入端，及一個輸出端；一個第一電阻，電連接在該第一放大器的輸出端與該調光輸出端之間；及一個齊納二極體，具有一個接地的陽極，及一個電連接到該調光輸出端的陰極。A dimming circuit comprising: a dimming input; a dimming output; a first amplifier having a non-inverting input electrically coupled to the dimming input, and a counter electrically coupled to the dimming output a phase input terminal and an output terminal; a first resistor electrically connected between the output terminal of the first amplifier and the dimming output terminal; and a Zener diode having a grounded anode and an electric Connect to the cathode of the dimming output. 如請求項1所述的調光電路，還包含：一個電容，電連接在該調光輸入端與地之間。The dimming circuit of claim 1, further comprising: a capacitor electrically connected between the dimming input terminal and the ground. 如請求項1所述的調光電路，還包含：一個第二電阻，電連接在該第一放大器的輸出端與地之間。The dimming circuit of claim 1, further comprising: a second resistor electrically connected between the output of the first amplifier and ground. 如請求項1所述的調光電路，還包含：一個電流源，電連接到該調光輸入端，且供應一個參考電流到該調光輸入端。The dimming circuit of claim 1, further comprising: a current source electrically connected to the dimming input terminal and supplying a reference current to the dimming input terminal. 如請求項4所述的調光電路，其中，該電流源包括：一個第二放大器，具有一個非反相輸入端、一個反相輸入端及一個輸出端；一個第三電阻，電連接在該第二放大器的反相輸入端與地之間； 一個第四電阻，具有一個電連接到該第二放大器之非反相輸入端的第一端，及一個接收一個參考電壓的第二端；一個第五電阻，電連接在該第二放大器的反相輸入端與該調光輸入端之間；一個第六電阻，電連接在該第二放大器的非反相輸入端與輸出端之間；及一個第七電阻，電連接在該第二放大器的輸出端與該調光輸入端之間。The dimming circuit of claim 4, wherein the current source comprises: a second amplifier having a non-inverting input, an inverting input, and an output; a third resistor electrically coupled to the Between the inverting input of the second amplifier and the ground; a fourth resistor having a first end electrically coupled to the non-inverting input of the second amplifier, and a second end receiving a reference voltage; a fifth resistor electrically coupled to the inverting of the second amplifier An input terminal and the dimming input terminal; a sixth resistor electrically connected between the non-inverting input terminal and the output terminal of the second amplifier; and a seventh resistor electrically connected to the output of the second amplifier Between the end and the dimming input. 如請求項1所述的調光電路，還包含：一個二極體，電連接在該第一電阻與該調光輸出端之間。The dimming circuit of claim 1, further comprising: a diode electrically connected between the first resistor and the dimming output. 如請求項6所述的調光電路，其中，該二極體具有一個電連接到該第一電阻的陽極，及一個電連接到該調光輸出端的陰極。The dimming circuit of claim 6 wherein the diode has an anode electrically coupled to the first resistor and a cathode electrically coupled to the dimming output.