TW201003612A - Light-source driving circuit - Google Patents

Abstract

A light-source driving circuit including a gray distinguishing unit, a parameter optimization module, a parameter calculation unit, a light dimmer control unit and a driving unit is provided. The gray distinguishing unit obtains a plurality of maximum gray values individually corresponded to several data blocks in an image data. The parameter optimization module generates an optimal period value according to a ratio of a standard current value and a predetermined current value. The parameter calculation unit obtains a specific ratio according to the optimal period value and a frame maximum gray value, and obtains a plurality of duty-cycle values by multiplying the maximum gray values of the data blocks to the specific ratio. The light dimmer control unit generates a plurality of light dimmer control signals according to the duty-cycle values and the predetermined current value. Then, the driving unit generates a plurality of driving pulses according to the light dimmer control signals.

Description

264〇9twf.doc/n 201003612 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a kind of light source; the optimization of the utilization parameters to achieve the reduction of work:; Xiao; = [Prior Art] To 'liquid crystal display (LCD) light and other advantages 'widely applied in various needs);: === quantity =:=: liquid; material rotation, Φ. ^ ^ and because the liquid crystal material itself does not have to send t: 1 Therefore, the LCD must be configured with a backlight module to provide the light source needed for the image to be untouched. In the process of providing the light source, the optical module of the rabbit is used to control the dimming range and brightness of the light-emitting component, so that the light source provided by the backlight module can conform to the U (four) panel brightness. , surface quality and color saturation and other properties. 1 is a circuit block diagram of a conventional light source driving circuit. Referring to the drawings, the light source driving circuit 100 includes a gray scale identifying unit 11 and a parameter calculating unit 120, a dimming control unit 13A, and a driving unit 14A. The grayscale recognition unit 110 divides an image data Data1 into a plurality of data blocks' and extracts the maximum grayscale value of each data block. Wherein, if the resolution of the image data Data1 is 8 bits, and the corresponding maximum grayscale value of the image is 255. After ~~6 201003612 26409twf.doc/n, as shown in the formula (1), the parameter calculation unit 120 calculates the work of each of the -# material blocks according to the maximum gray level value of each data block. cycle. VGi

Dj two (1)

Where Dj is the working period corresponding to the jth data block, ν(^ is the maximum grayscale value corresponding to the first data block, and j is a positive integer. J f" o , again, dimming control The unit 130 generates a plurality of dimming control signals according to the working period corresponding to the data block and the gauge & current value Ispee '. Thereby, the driving unit 140 can generate the plurality of driving signals according to the dimming control signals. The pulse waves PUU~PUln sequentially drive a plurality of light emitting diodes (not shown) disposed in the backlight module, wherein the current of the light emitting diodes is not greater than the standard current value Ispec. Yes, since the duty cycle of the driving pulse waves pUii~pUin is between 0% and (8)%, when the maximum grayscale value of the data block is 255, the driving unit 140 will generate a duty cycle of 1%. The pulse wave is driven. At this time, as shown in FIG. 1B, in each display period τ, the current flowing through the light-emitting diode will be maintained at the standard current value Ispec, and thereby the backlight of the maximum brightness is generated. When the conventional technology wants to increase the maximum brightness of the backlight, It is known that the light source driving circuit 100 must increase the specification current value Ispec to thereby increase the voltage level of the driving pulse waves PUU 〜 PUln. At this time, the power consumption of the conventional light source driving circuit 100 will be relatively increased. The junction temperature of the body will also increase with the increase of the standard current value Ispec, thereby reducing the service life of the backlight module. 7 201003612 \j / l\jix V 26409twf.doc/n [Summary] The present invention provides a light source driving circuit power consumption in order to reduce the backlight of the circuit itself. The present invention provides a light source driving circuit system cost. The present invention provides a light source driving circuit for driving a plurality of components. The light source driving circuit includes a gray scale identification unit, and the parameter is the most

Module, - parameter calculation unit, - dimming control element and - drive unit ^. The 'gray identification sheet TdX divides the image data into a plurality of sub-blocks' to extract the maximum grayscale value corresponding to each of the data blocks. Thereafter, the parameter optimization module generates an optimization period value according to a ratio of a standard current value to a specific current value, wherein the specification current value is less than the constant current value. On the other hand, the parameter calculation unit obtains a specific ratio according to the optimization period value and the maximum gray scale value of one plane. Thereafter, the parameter calculation unit further multiplies the maximum grayscale value of the data block by a specific ratio to obtain a plurality of duty cycle values. Thereby, the dimming control unit generates a plurality of dimming control signals according to the duty cycle value and the specific current value. The driving unit generates a plurality of driving pulse waves required to drive the light emitting elements according to the dimming control signal. In an embodiment of the invention, the duty cycle of the driving pulse wave is equal to the duty cycle value, and the current flowing through the light emitting element is not greater than a specific current value. The invention further provides a light source driving circuit for driving a plurality of hairs 8 201003612

N 26409twf.doc/n Optical components. The light source driving circuit comprises a gray level identification unit, a parameter optimization module, a parameter calculation unit, a dimming control unit and a driving unit. The grayscale identification unit is configured to divide an image data into a plurality of data blocks, and extract the maximum grayscale value corresponding to each of the data blocks. Furthermore, the parameter optimization module generates an optimized current value according to a ratio of a standard current value to a specific period value, wherein the specific period value is less than 1 〇f'. On the other hand, the parameter calculation unit is based on the most The optimized current value and the maximum grayscale value of the picture are obtained to obtain a specific ratio. In addition, the parameter calculation unit further multiplies the maximum grayscale value of the data block by a specific ratio to obtain a plurality of current values. Thereby, the dimming control unit generates a plurality of dimming control signals according to the current value and the specific period value. The driving unit is configured to generate a plurality of driving pulse waves required to drive the light emitting element according to the dimming control signal. In one embodiment of the present invention, the duty cycle of the driving pulse wave is not greater than a specific period value and the current flowing through the light-emitting element is equal to the current value, respectively. The light source driving circuit is suitable for the backlight module. Further, the light emitting elements are disposed in the backlight module and are respectively composed of “light emitting diodes.” The invention utilizes a parameter optimization module to generate the most The optimization period value [疋 optimizes the current value. Therefore, the light source driving circuit can adjust the cycle of the secret wave or the 疋 voltage level according to the optimization, the period value or the better recording. The working period of the driving pulse wave is less than 100〇/〇, 9 201003612 ... one, V 26409twf.doc/n and the current of the π-element is greater than the standard current value. So, the system cost technology is compared The above-mentioned features and advantages of the present invention will be more apparent and easy to understand, and the preferred embodiment will be described below. And with the closed type, DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment] Before explaining the spirit of the present invention by way of examples, it is first assumed that the light_(four) way_of-f domain group enumerated in each embodiment. Further, the light source of each embodiment 4, the meaning circuit Further, a plurality of light-emitting elements (not taken out) arranged in the backlight module are read by the tank, and the light-emitting elements are generated by the light-emitting elements, wherein the light-emitting elements can be respectively composed of a light-emitting diode. In order to limit the present invention, those skilled in the art can also change the application mode of the light source driving circuit according to the spirit of the present invention. Fig. 2A is a diagram showing the road structure of the light source driving circuit according to an embodiment of the present invention. 2A, the light source driving circuit 2 includes a grayscale identification unit 210, a parameter calculation unit 22, a dimming control unit 23, a driving unit 240, and a parameter optimization module 25A. The gray level identification unit 21 The parameter optimization unit 250 is electrically connected to the parameter calculation unit 220. The parameter calculation unit 220 is electrically connected to the dimming control unit 23, and the s-peripheral control unit 230 is electrically connected to the driving unit 240. In the overall operation, the grayscale identification unit 210 is configured to divide an image data Data2 into a plurality of data blocks DB2l~DB2n. After that, the grayscale identification unit 210 compares the grays included in the data block Db2 and the DB2n. The order 201003612 ... too v, W 26409twf.doc / n value 'to extract the data block DB21 ~ DB2ng from the corresponding maximum gray level value VG ^ VGh. For example, if the data block Db27 includes the gray level value P21 ~ P24 'and gray scale value P23> gray scale value P2l> gray scale value P22> gray scale value P24. At this time, the 'gray scale identification unit 21 〇 will compare the size of the gray scale values p21 to p24' and extract the gray scale from the middle The value P23 is taken as the maximum grayscale value VG27 corresponding to the data block DB27. On the other hand, the parameter optimization module 250 will follow the standard current value.

The ratio of Ispec to the specific current value Ipre produces an optimized period value D()p, wherein the gauge current value ispee is smaller than the specific current value Ipre. After that, the parameter calculation unit 220 obtains a specific ratio RT2 according to the optimization period value Dqp and the maximum grayscale value VGmax of the facet. In addition, the parameter calculation unit 220 further sets the maximum grayscale value VG21 of the data block DB^DBh. VG2n is multiplied by a specific ratio RT2 to obtain a plurality of duty cycle values D2i to D2n. For example, the data block DB21 is taken as an example. At this time, the parameter calculation unit 220 does not obtain the specific ratio RT2 in accordance with the ratio of the optimization period value D()p to the maximum grayscale value VGmax of the screen as in the equation (2). Thereafter, as shown in the equation (3), the parameter calculation unit 220 multiplies the maximum grayscale value 乂021 by the specific ratio RT2 to obtain the duty cycle value j)21.

D (2)

RT2-— VG max D21 =RT2*VG21 (3) In other words, if D μ is used to represent the ith duty cycle value, v & 丨 is used to represent the ith maximum gray scale value, and n is a positive integer. , i is an integer and the parameter calculation unit 220 calculates the duty cycle value DfDh according to the equation (4). In addition, in the present embodiment, if the resolution of the image data Data2 201003612 ... * a---W 26409twf.doc/n is k bits, the corresponding maximum gray scale value of the facet. m&x is 2 ' k is a positive integer. 〇2i: DQp = VG2i: VGmax (4) After the dimming control unit 230 generates a plurality of dimming control signals S2i to S2 according to the duty cycle value d2i~ and the specific current value ipre'. . Thereby, the driving unit 240 generates a plurality of driving pulse waves PU2i to pU2n required for driving the light-emitting elements in accordance with the dimming control signal S2 wide S2n. It is worthwhile to note that the duty cycle of the drive pulse 卩仏^~ is equal to the duty cycle value. In other words, the light source driving circuit 200 can achieve the mechanism of dimming by adjusting the duty cycle of driving the pulse PU2 wide PUh. Further, in the present embodiment, the current of the light-emitting element is not greater than the specific current value Ipre.

2B is a current waveform diagram of the light-emitting element of the embodiment of FIG. 2A compared with the prior art. The reference numeral 201 is used to indicate the current waveform generated by the embodiment of FIG. 2A, and the reference numeral 2 G 2 is used to indicate the technology. The resulting current waveform. In the embodiment of FIG. 2A, since the normalized current value 'is less than the specific current value I, as shown by the current waveform 201, in each display period τ, the light source driving circuit generates a driving pulse wave whose guardian period is less than just %, This results in a maximum brightness of 70 pieces of light. It is known that the electric current flowing through the light-emitting element is held at a specific current and larger than the normal current value Ispee, and thus compared with the prior art = the embodiment can increase the maximum brightness of the Wei-phase phase. In contrast, the mode of the embodiment uses a less illuminating tree to achieve the same brightness of the backlight. This 201003612 ------*- ^ 26409 twf.doc/n example will help reduce the backlight mode The system cost of the group. Continuing with reference to Figure 2A, the parameter optimization module 250 includes an energy calculation unit 251 and a parameter generation unit 252. Wherein, as shown in the formula (5), the energy calculation unit 251 is configured to multiply the display period value τ by the specification current value, and accordingly generate a system energy value psys. Thereafter, as shown in the equation (6), the parameter generation unit 252 divides the system energy value Psys by the display period value τ and the specific current value Ipre, and accordingly generates an optimization period value D. P -Txl 'sys spec

D

P op

Txl (5) (6) pre In other words, the parameter optimization module 250 mainly uses the normalized current value and the specific current value Ipre to generate the optimized period value Dqp. It is worth mentioning that, in this embodiment, the display period value T is inversely proportional to the update frequency of the image data Data2. FIG. 3A is a two-way architecture diagram of a light source driving circuit q according to another embodiment of the present invention. Referring to Fig. 3A, the light source driving circuit 3A includes a gray scale discrimination unit 104, a parameter calculation unit 32, a dimming control unit 330, a driving unit 340, and a parameter dazzling module and ho. The grayscale identification unit 310 and the parameter optimization module 35 are electrically connected to the parameter calculation unit "0", respectively. For the parameter, the calculation unit S 320 is electrically connected to the dimming control unit 33A. And the " Zhouguang control unit A 330 is electrically connected to the driving unit 340. In the overall operation, the grayscale identification unit 310 is configured to divide the image data into a plurality of data blocks called a wide team. After that, the grayscale discriminates the training of the data block DB31~DB3n to include the grayscale 13 201003612 ---------V 26409twf.doc/n value to extract the data block. The maximum gray scale value VG^VGh corresponding to each of 31~〇6311. For example, if the data block DB37 includes grayscale values P31 to P34, and the grayscale value P32> grayscale value P34> grayscale value P33> grayscale value P31. At this time, the 'gray identification unit 31' will compare the magnitudes of the grayscale values p31 to p34, and extract the grayscale value P32 from the middle as the maximum grayscale value VG37 corresponding to the data block plus. On the other hand, the parameters The optimization module 350 generates an optimized current value according to the ratio of the standard current value Ispec to the specific period value Dpre, wherein the specific period value Dpre is less than 1. After that, the parameter calculating unit 32〇 is based on the optimized current value. The Iop and the maximum grayscale value VGmax of the facet obtain a specific ratio RT3. Further, the parameter calculation unit 32 multiplies the maximum grayscale values VG31 to VG3n of the data block DBn-DBh by a specific ratio RT3 to obtain a majority. For example, as shown in the equation (7), the parameter calculation unit 32 取得 obtains the specific ratio RT3 according to the ratio of the optimized current value Iop to the maximum grayscale value VGmax of the facet. Then, as shown in the equation (8), the parameter calculation unit 32 相 multiplies the maximum gray scale value VG^ by the specific ratio RT3 to obtain the current value ι3ι. RT3 II-i-VGmax I31=RT3*VG31 (7) (8) In other words If Isi is used to represent the ith current value, VG3i is used. Indicates the i-th maximum grayscale value, η is a positive integer, and i is an integer. Then, the parameter calculation unit 320 calculates the current value l31 to l3n according to the equation (9). Further 'in the present embodiment' / [ If the resolution of the image data Data3 is a bit, the corresponding grayscale value of the corresponding surface is ¥〇11^ is 2k, and k is positive 14 26409twf.doc/n 201003612

---------N Integer. L3i: I 〇 p = VG3i: VGmax (9), after which the dimming control unit 33 generates a plurality of dimming control signals S31 to S3n according to the current value I and the specific period value Dpre '. Thereby, the drive unit i will generate the recorded pulse waves PU3i to PU3n required to drive the light-emitting elements in accordance with the dimming control signals S3i to & It should be noted that the currents of the light-emitting elements are equal to the current values l3i to “n. In other words, (''the light source driving circuit is finely adjusted by adjusting the voltage levels of the driving pulses PU21 to PU2n to achieve dimming. In addition, in this embodiment, the duty cycle of the driving pulse wave PUm-PU^ is not greater than a specific period value. FIG. 3B is a current waveform diagram of the light-emitting element in the embodiment of FIG. 3A compared with the prior art. The reference numeral 3〇1 is used to indicate that the current waveform generated by the embodiment of FIG. 3A is denoted by reference numeral 3〇2 for indicating the electric=waveform generated by the prior art. In the embodiment of FIG. 3A, as shown by the current waveform 3〇1. In each display period T, the light source driving circuit 300 generates a driving pulse wave whose duty cycle is equal to the 疋 疋 period value Dpa, so as to cause the optical element to generate maximum brightness. Further, since the specific period value Dpre is maintained at less than 丨In this case, the current value l3i flowing through the light-emitting element at this time is also greater than the standard current value Ispec. Therefore, compared with the prior art, the embodiment of FIG. 3 can also be increased without increasing the power consumption of the circuit itself. Illuminate The maximum brightness of the device. Relatively speaking, the backlight module of the embodiment of FIG. 3A can also use less illumination components to achieve the same brightness backlight, so the SA embodiment will also help to reduce the backlight module. System cost. , 15 201003612 ......—N 26409twf.doc/n In summary, the present invention uses a parameter optimization module to generate an optimization period based on a standard current value. The value or the optimized current value, whereby the driving pulse generated by the driving unit has a duty cycle = two 100%, and the current of the light-emitting element is greater than the standard current value. Thus, the conventional technology is In contrast, the present invention can increase the maximum brightness of the light-emitting element without increasing the power consumption of the circuit itself, and further contribute to the system cost of the optical module.

While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the patent application scope attached. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a circuit block diagram of a conventional light source driving circuit. FIG. 1B is a diagram showing current waveforms for explaining the embodiment of FIG. 1A. Figure 2A is a circuit diagram showing a light source driving circuit in accordance with an embodiment of the present invention. 2B is a current waveform diagram of the illuminating element in the embodiment of FIG. 2a compared to the prior art. Fig. 3A is a circuit diagram showing a light source driving circuit according to another embodiment of the present invention. Figure 3B is a current waveform diagram of the illuminating element of the embodiment of Figure 3A compared to conventional techniques. [Main component symbol description] 100: conventional light source driving circuit 16 26409twf.doc/n 201003612 w 110, 210, 310: grayscale identification unit 120, 220, 320: parameter calculation unit 130, 230, 330: dimming control unit 140, 240, 340: drive unit 200, 300: light source drive circuit 250, 350: parameter optimization module 251, 351: energy calculation unit 252, 352: parameter generation unit 201, 202, 301, 302: current waveform Datal , Data2, Data3: Image data DB 1~DB211, DB3I~DB311.Grant block P21~P24, P31~P34: Grayscale value VG2 wide VG2n, VG3 wide VG3n: Maximum grayscale value T: Display period ISpec: Normalized current value VGmax: maximum grayscale value of the screen

Ipre: specific current value

Dop: Optimized period value D21~D2n: duty cycle value S21~S2n, S31~S311. Dimming control signal PU„~PUln, PU2 wide PU2n, PU3 wide PU3n: drive pulse wave

Dpre : Specific period value Ι〇ρ : Optimized current value 3 wide! 3η . Current value 17

Claims (1)

26409twf.d〇c/n 201003612 vv X. Patent application scope: 1. A kind of light source driving circuit for driving a plurality of illuminating elements S hai light source driving circuit including: dry material ε block will be - image (four) 4 彳 number of turns Each of the capital blocks and the maximum gray scale value corresponding to each of the recorded (four) blocks; the middle and the ^'s number of the optimized module' are used to determine the current value and the specific ^The ratio of the edges is generated - the optimization period value, wherein the gauge is smaller than the specific current value; the value s is a parameter different unit, and is used according to the optimization period value and the - surface, the large gray scale value - a specific ratio, and multiplying the maximum fire value of the dump blocks by the specific ratio to obtain a plurality of duty cycle values; + & a dimming control unit for determining the work cycle value and the specific The current value is used to generate a plurality of dimming control signals; and the driving unit is configured to generate a plurality of driving pulse waves required to drive the light emitting elements according to the dimming control signals. 2. The light source driving circuit of claim 1, wherein the parameter optimization module comprises: an energy calculation unit for multiplying a display period value by the specification current value, and generating a system energy value; and a parameter generating unit configured to divide the system energy value by the display period value and the specific current value, and thereby generating the optimization period value. 3. The light source driving circuit of claim 2, wherein the display period value is inversely proportional to an update frequency of the image data. 4. The light source driving circuit according to claim 1, wherein 18 26409 twf.doc/n 201003612 the resolution of the image data is k bits, and #, where k is a positive integer & The maximum grayscale value of Hai disease is 5. The source of light as described in the patent application (4) 该 The secret _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The current flowing through the light-emitting elements is in a large-scale manner. 7. The light source according to item i of the patent application is composed of a light-emitting diode. Pack 8: The light source_circuit as described in the scope of the patent application, applies to the - backlight module 'and the light-emitting elements are configured to operate the light source i (four) way to rotate the plurality of material elements, and the ί. a white identification unit for arranging an image data book octagonal material block and aging the maximum gray scale 1 shell-parameter optimization module corresponding to each of the data blocks, according to the standard current value and a ratio of: an optimized current value, wherein the specific period π a parameter calculation unit is configured to obtain a specific ratio according to the optimized current value and the maximum gray scale value of the book, and the data is obtained a grayscale value of the block is multiplied by the specific ratio to obtain a plurality of current values; a dimming control unit for generating a plurality of dimming control signals according to the current values and the specific period value'; A driving unit is configured to generate a plurality of driving pulse waves required for driving the light-emitting elements according to the dimming control signals. 10. The light source driving circuit of claim 9, wherein the parameter optimization module comprises: an energy calculation unit for multiplying a display period value by the specification current value, and Generating a system energy value; and a parameter generating unit for dividing the system energy value by the display period value and the specific period value, and generating the optimized current value accordingly. 11. The light source driving circuit of claim 10, wherein the display period value is inversely proportional to an update frequency of the image data. 12. The light source driving circuit of claim 9, wherein the resolution of the image data is k bits, and the maximum gray level value of the pupil is 2k ’ where k is a positive integer. 13. The light source driving circuit of claim 9, wherein the driving pulse wave has a duty cycle not greater than the specific period value. 14. The light source driving circuit of claim 9, wherein currents flowing through the light emitting elements are equal to the current values, respectively. 15. The light source driving circuit of claim 9, wherein the light emitting elements are each composed of a light emitting diode. The light source driving circuit as described in claim 9 wherein the light source driving circuit is applied to a backlight module, and the light emitting elements are disposed in the backlight module. 20