TWI544833B - A method for driving a light emitting diode wafer - Google Patents

Description

Method for driving a light emitting diode chip

The invention relates to LED driving of a light-emitting diode; in particular to a method for driving a light-emitting diode wafer.

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, and the required operating voltage or operating current are different. In order to drive a light-emitting diode wafer of such a plurality of specifications, the current approach is to develop a driving device for each of the light-emitting diode chips.

However, for the manufacturer of the light-emitting diode lighting device, it is necessary to manufacture a driving device for each size of the LED chip, which not only increases the pressure of the driving device inventory, but also cannot be priced, resulting in manufacturing cost. The high price of the LED lighting device cannot be lowered, which is one of the reasons why the current LED lighting device is still not popular. If a light-emitting diode chip driving method capable of driving a plurality of voltages or a plurality of currents can be developed, the pressure of the driving device of the light-emitting diode chip can be reduced, and the manufacturing cost can be effectively reduced.

In view of the above, an object of the present invention is to provide a method for driving a light-emitting diode wafer that can be applied to a light-emitting diode wafer that drives different voltages or currents.

In order to achieve the above object, the method for driving a light-emitting diode chip is applied to a device including a plurality of switch switches and a drive unit, and the combination of the switch switches is turned on and off. 2 ⁿ , where n is the number of switching switches, the driving unit is electrically connected to a light emitting diode chip, and the method comprises the following steps: A. controlling the opening and closing states of the switching switches to be a combination state of 2 ⁿ One of the samples, and generates a reference voltage corresponding to the combined state; B, according to the magnitude of the reference voltage, controlling the driving unit to output a corresponding operating voltage to the LED chip; C, detecting the And outputting the operating voltage to the LED chip, and controlling the driving unit to adjust the output voltage to the LED chip to fall within the set voltage range when the measured operating voltage is out of a set voltage range.

The invention further provides a method for driving a light-emitting diode wafer, which is applied to a device comprising a plurality of switch switches and a drive unit, wherein the combination of opening and closing of the switch switches is 2 ⁿ , wherein n In order to switch the number of switches, the driving unit is electrically connected to a light emitting diode chip, and the method comprises the following steps: A. controlling one of the combination of the opening and closing states of the switching switches to be 2 ⁿ , And generating a reference voltage corresponding to the combined aspect; B, controlling the output current corresponding to the output of the driving unit to the LED according to the magnitude of the reference voltage; C, detecting the output to the LED The working current of the polar body wafer controls the operating current of the driving unit to adjust the output to the LED chip to fall within the set current range when the measured operating current is out of a set current range.

The effect of the invention is that the reference voltage of different voltage values can be used to enable the driving unit to output electric energy of different working voltages or working currents to the LED chip, thereby achieving the purpose of integrating a plurality of driving devices into one. Effectively improving the conventional driving device can only be applied to the inconvenience of a single size of the LED chip.

1‧‧‧ drive

10‧‧‧Drive unit

12‧‧‧Voltage detection unit

14‧‧‧voltage circuit

16‧‧‧Toggle switch

162‧‧‧ stitches

164‧‧‧ Jumper

18‧‧‧ arithmetic unit

20‧‧‧Control unit

2‧‧‧ drive

22‧‧‧current detection unit

P‧‧‧Power supply

L‧‧‧Light Emitter Wafer

V‧‧‧voltage source

Vref‧‧‧reference voltage

R1~R5‧‧‧ resistance

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram of a driving device to which the first preferred embodiment of the present invention is applied.

Fig. 2 is a view showing an embodiment of a resistor divider circuit of the driving apparatus of the first preferred embodiment.

3 is a flow chart of a method for driving a light emitting diode wafer in the above preferred embodiment.

Figure 4 is a block diagram of a driving device to which the second preferred embodiment of the present invention is applied.

FIG. 5 is a flow chart of a method for driving a light emitting diode wafer according to the second preferred embodiment.

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, which is a method for driving a light-emitting diode wafer according to a first preferred embodiment of the present invention. The driving device 1 includes a driving unit 10, a voltage detecting unit 12, a voltage dividing circuit 14, a plurality of switching switches 16, an arithmetic unit 18 and a control unit 20.

The driving unit 10 is electrically connected to a power source P and a light emitting diode chip L. The driving unit 10 receives the power of the power source P and converts it into a working voltage and an operating current required by the LED chip L. Output. The drive unit 10 is controllably varying the magnitude of the operating voltage. In practice, the drive unit 10 can be designed based on circuits of the PWM, half bridge, Buck, Boost, and the like.

The voltage detecting unit 12 is electrically connected to the driving unit 10 for detecting an operating voltage of the driving unit 10 outputted to the LED chip L.

In this embodiment, the voltage dividing circuit 14 is a resistor divider circuit electrically connected to the switching switches 16, and the switching switches 16 are electrically connected to a voltage source V. In this embodiment, each of the changeover switches 16 includes a two-pin (Pin) 162 and a jumper 164. The two pins 162 are electrically connected to the voltage source V and the voltage dividing circuit 14, respectively. The 164 is detachably connected to the two pins 162 such that each of the changeover switches 16 is in an open or short circuit state. The voltage dividing circuit 14 divides the voltage source V to generate a reference voltage Vref. As shown in FIG. 2, the voltage dividing circuit 14 of the present embodiment includes a plurality of parallel resistors R1 R R4 and a resistor R5 connected in series with resistors R1 R R4. The resistors R1 R R3 are connected through the switch 16 . To the voltage source V, the resistor R4 is directly connected to the voltage source V, and the resistors R1 to R4 are commonly grounded through the resistor R5, whereby the voltage division of the resistor R5 forms the reference voltage Vref.

The components defining the on and off states of the switch 16 constitute a plurality of combinations. The number of the switches 16 is n, and the number of combined states is 2 ⁿ . For example, the three switching switches 16 can be combined to form a single (2 ³ ). The combination of the three switches 16 is matched with the resistors R1 R R4 of different resistance values, so that the resistors R1 R R4 form an equivalent resistance of eight different resistance values. The jumper 164 of the changeover switch 16 is combined or separated from the corresponding pin 162 to make the equivalent resistance formed by the voltage dividing circuit 14 one of eight resistance values, in other words, the partial piezoelectricity. Circuit 14 can output a reference voltage for one of eight voltage values.

The computing unit 18 is electrically connected to the voltage detecting unit 12 and the voltage dividing circuit 14 , and the computing unit 18 is electrically connected to the driving unit 10 through the control unit 20 . The operation unit 18 is based on the reference voltage Vref The driving unit 10 controls the driving unit 10 by outputting a corresponding electrical signal, so that the driving unit 10 outputs the operating voltage corresponding to the magnitude of the reference voltage Vref, and the operating voltage output by the driving unit 10 is proportional to the operating voltage. Reference voltage. For example, the driving unit can output an operating voltage of one of 28V to 21V, and the maximum reference voltage Vref corresponds to an output operating voltage of 28V, and the next largest reference voltage Vref corresponds to an output operating voltage of 27V. This type of push. In addition, the computing unit 18 compares the voltage measured by the voltage detecting unit 12 with the reference voltage Vref, and controls the driving unit 10 through the control unit 20, so that the operating voltage output by the driving unit 10 is maintained. Within a set voltage range corresponding to the operating voltage.

Therefore, the driving method shown in FIG. 3 can be performed by using the driving device 1 described above. First, the user sets the opening and closing states of the switching switches 16 according to the voltage specifications of the connected LED chips L. In one of the combined forms of 2 ⁿ , the driving unit 10 outputs a voltage that conforms to the specification of the LED of the light-emitting diode. For example, the voltage outputted by the driving unit 10 is one of 28V~21V, and when the voltage specification of the connected LED chip L is 28V, the user connects the three jumpers 164. The corresponding pin 162 is connected. At this time, the resistors R1 R R4 are connected in parallel, and the equivalent resistance is the smallest, so that the voltage of the voltage source V is divided by the voltage of the resistor R5, and the maximum reference voltage Vref is output to the arithmetic unit. 18. The arithmetic unit 18 is further controlled by the control unit 20 to control the driving unit 10 to output an operating voltage of 28 V to the LED array L.

Then, the computing unit 18 continuously detects the operating voltage through the voltage detecting unit 12 and controls the driving unit 10 through the control unit 20 to maintain the operating voltage outputted to the LED chip L at the set voltage. Within the range, the measured operating voltage is out of the set voltage range In addition, the driving unit 10 is controlled to adjust the operating voltage outputted to the LED substrate L to fall within the set voltage range, thereby forming a constant voltage driving device 1.

In use, if the LED diode L of the connection specification of 27V is replaced, the corresponding jumper 164 is detached again, and the reference voltage Vref is further lowered by one step, that is, the drive can be controlled in the same manner. Unit 10 is enabled to output 27V of electrical energy. Similarly, after all the jumpers 164 are detached, the equivalent resistance of the resistors R1 to R4 is the largest, so that the voltage division of the resistor R5 is the smallest, and the output reference voltage Vref is the smallest, corresponding to the operating voltage of 21V.

According to the above, the use of the jumper 164 and the pin 162 as the changeover switch 16 in the present embodiment can effectively reduce the component cost. The driving device 1 is formed into a constant voltage driving device 1 capable of outputting different voltages by using various combinations of the switching switches 16 to achieve the purpose of integrating a plurality of constant voltage driving devices, and the driving device can effectively improve the conventional driving device. The inconvenience of a standard light-emitting diode chip L.

Referring to FIG. 4, a driving device 2 for applying the method for driving a light-emitting diode wafer according to a second preferred embodiment of the present invention has substantially the same structure as that of the first embodiment, except that the The driving unit 10 is controlled to change the magnitude of the output operating current, and the computing unit 18 controls the driving unit 10 to output the corresponding driving signal through the control unit 20 according to the magnitude of the reference voltage Vref, so that the driving unit 10 outputs The operating current corresponding to the magnitude of the voltage Vref is referenced, and the operating current output by the driving unit 10 is proportional to the reference voltage Vref. In addition, the driving device 2 of the present embodiment is not provided with the voltage detecting unit 12, but is provided with a current detecting unit 22, and the current detecting unit 22 detects the operating current of the driving unit 10 outputted to the LED chip L. And converting it into a corresponding voltage signal is input to the operation unit 18. The computing unit compares the voltage signal outputted by the current detecting unit 22 with the reference voltage Vref and transmits the control unit 20 The driving unit 10 is controlled to maintain the operating current output by the driving unit 10 within a set current range corresponding to the operating current.

Similarly, the drive device 2 performs the driving method shown in FIG. First, the user sets the on and off states of the switch 16 according to the current specification of the connected LED chip L to form one of the combined views. For example, the driving unit can output a current of one of 400 mA to 330 mA, and when the current specification of the connected LED chip L is 400 mA, the three jumpers 164 are connected. Corresponding pins 162 are generated to generate a maximum reference voltage Vref. The arithmetic unit 18 is caused to control the driving unit 10 to output an operating current of 400 mA to the light-emitting diode wafer L through the control unit 20.

Then, the computing unit 18 continuously detects the operating current through the current detecting unit 22 and controls the driving unit 10 through the control unit 20 to maintain the operating current outputted to the LED chip L at the set current. In the range, when the measured operating current is out of the set current range, the driving unit 10 is controlled to adjust the operating current outputted to the LED chip L to fall within the set current range, thereby forming a constant current driving. Device 2.

Thereby, the drive unit 10 can output one of eight currents of 400 mA, 390 mA, 380 mA, 370 mA, 360 mA, 350 mA, 340 mA, and 330 mA by setting the combination of the switches 16. Thereby, a constant current driving device 2 capable of outputting different currents is formed, thereby achieving the purpose of integrating a plurality of constant current driving devices, and effectively improving the inconvenience that the conventional driving device can only be applied to a single-dimension LED chip.

The above is only a preferred embodiment of the present invention, and equivalent changes to the scope of the present invention and the scope of the patent application are intended to be included in the scope of the present invention.

Claims (10)

A method for driving a light-emitting diode chip is applied to a constant voltage driving device including a plurality of switching switches and a driving unit, and the combination of opening and closing of the switching switches is 2 ⁿ , wherein n is The number of the switch, the driving unit is electrically connected to a light emitting diode chip, the method comprises the following steps: A, controlling one of the combination of the opening and closing states of the switch to 2 ⁿ , and Generating a reference voltage corresponding to the combined state; B, controlling a corresponding operating voltage of the driving unit to output the LED chip according to the magnitude of the reference voltage; and C, detecting the output to the light emitting diode The working voltage of the polar body wafer controls the driving unit to adjust the output voltage to the LED chip to fall within the set voltage range when the measured operating voltage is out of a set voltage range corresponding to the operating voltage. The method for driving a light-emitting diode chip according to claim 1, comprising a voltage source and a voltage dividing circuit electrically connected to the voltage source, wherein the voltage dividing circuit divides the voltage source The reference voltage is generated; in step A, the size of the reference voltage generated by the voltage dividing circuit is controlled according to a combination of the switching switches. The method of claim 2, wherein the voltage dividing circuit comprises a resistor divider circuit electrically connected to the voltage source and the resistor divider circuit Between the two combinations of the switch switches in step A, the resistor divider circuit forms a specific equivalent resistance to divide the voltage source. The method for driving a light-emitting diode chip according to claim 3, wherein each of the switch switches includes a pin and a jumper, and the two pins are electrically connected to the voltage source and the And a resistor divider circuit, the jumper is detachably connected to the two pins, and in step A, each of the jumpers is adjusted to connect or detach the corresponding two pins to form one of the combined views. The method for driving a light-emitting diode wafer according to claim 1, wherein the operating voltage output by the driving unit in step B is proportional to the reference voltage. A method for driving a light-emitting diode chip is applied to a constant current driving device including a plurality of switching switches and a driving unit, wherein the combination of opening and closing of the switching switches is 2 ⁿ , wherein n is The number of the switch, the driving unit is electrically connected to a light emitting diode chip, the method comprises the following steps: A, controlling one of the combination of the opening and closing states of the switch to 2 ⁿ , and Generating a reference voltage corresponding to the combined aspect; B, controlling, according to the magnitude of the reference voltage, a corresponding operating current of the driving unit to the LED chip; and C, detecting the output to the LED The working current of the polar body wafer controls the driving unit to adjust the output current to the LED chip to fall within the set current range when the measured operating current is out of a set current range corresponding to the operating current. The method for driving a light-emitting diode chip according to claim 6, comprising a voltage source and a voltage dividing circuit electrically connected to the voltage source, wherein the voltage dividing circuit divides the voltage source Generate the reference voltage; in step A And controlling the magnitude of the reference voltage generated by the voltage dividing circuit according to a combination of the switching switches. The method for driving a light-emitting diode chip according to claim 7, wherein the voltage dividing circuit comprises a resistor voltage dividing circuit, and the switching switches are electrically connected to the voltage source and the resistor voltage dividing circuit Between the two combinations of the switch switches in step A, the resistor divider circuit forms a specific equivalent resistance to divide the voltage source. The method for driving a light-emitting diode chip according to claim 8, wherein each of the switch switches includes a pin and a jumper, and the two pins are electrically connected to the voltage source and the And a resistor divider circuit, the jumper is detachably connected to the two pins, and in step A, each of the jumpers is adjusted to connect or detach the corresponding two pins to form one of the combined views. The method for driving a light-emitting diode wafer according to claim 6, wherein the operating current outputted by the driving unit in step B is proportional to the reference voltage.