CN201327518Y - Testing configuration for a light emitting diode backlight module - Google Patents
Testing configuration for a light emitting diode backlight module Download PDFInfo
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- CN201327518Y CN201327518Y CN 200820235214 CN200820235214U CN201327518Y CN 201327518 Y CN201327518 Y CN 201327518Y CN 200820235214 CN200820235214 CN 200820235214 CN 200820235214 U CN200820235214 U CN 200820235214U CN 201327518 Y CN201327518 Y CN 201327518Y
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- emitting diode
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Abstract
The utility model provides a testing configuration for a LED (light emitting diode) backlight module, which is suitable for the field of the LED (light emitting diode) testing technology. The testing configuration can be used for testing the light emitting diode backlight module. The testing configuration with the LED (light emitting diode) comprises a direct current power module, a control unit and a plurality of electronic loads, wherein the control unit can modulate the impedance of the electronic loads, so as to achieve the purpose of adjusting the current strength of each serial line source in the LED (light emitting diode). The testing configuration can not influence the whole response speed; and the direct current power module is used for adjusting the impedance of the electronic loads through the control unit, so as to provide wider current use scope and lower ripple current. The utility model is suitable for backlight panels with different dimensions.
Description
Technical field
The utility model relates to the LED technical field of measurement and test, relates in particular to a kind of test structure of light-emitting diode (LED) backlight module.
Background technology
Because LCD (Liquid Crystal Display) is a non-self-emission display apparatus, thus the conducting of need by the external light source light beam whether so that display capabilities to be provided, i.e. the function of backlight module.
(Light Emitting Diode LED) has that operating voltage is low, glorious degrees is high, response speed is fast, the advantage of long service life, so can be applicable among the backlight module of display because light emitting diode.
When designing led drive circuit in the past, be the mode that adopts fixed voltage circuit or constant-current circuit,, adopt the constant-current circuit driving LED so change because fixed voltage circuit may make parallel circuit cause the situation of each LED brightness disproportionation.And adjust the electric current of constant-current circuit at present, major part is with pulse-width modulation (PulseWidth Modulation; PWM) mode realizes.
Utilize the dimming mode of pwm circuit as LED, have two types haply, comprise boost type and buck, but the shortcoming of pwm circuit is: circuit itself does not have the function of fixed current, if when voltage surpasses limit value, may partly cause damage to other assembly of LED or circuit.Please refer to Fig. 1,101 expression input signals, 102 expression comparers, 103 expression output waveforms among Fig. 1, the transverse axis T express time, longitudinal axis V represents voltage, the principle of its modulation is the work period of change-over switch (Duty Cycle) for a change, obtain the percent value in the cycle of exporting, and the mode of Control current takes the mode of average current to calculate usually, calculate average current value by the back coupling value, if the current value that is calculated this moment does not meet the average current value of setting, then continue the modulation work period (Duty Cycle), meet setting value up to average current value.So in general, pwm circuit has bigger ripple current (ripple current) easily, again can be comparatively numerous and diverse because of feedbacking with control loop, so therefore cause loop speeds slower.
Utilize the led drive circuit of pwm circuit design in addition, the matrix size of its LED-backlit module mostly is fixing, if want the size of adjusting module matrix, just entire circuit must be redesigned.
Therefore, need a kind of technical scheme, to overcome the problems referred to above.
The utility model content
The purpose of this utility model is to provide a kind of test structure of light-emitting diode (LED) backlight module, is intended to solve the problem to the LED-backlit module testing.
The utility model is to realize like this, a kind of test structure of light-emitting diode (LED) backlight module, be used for to compose in parallel by a plurality of line source serials and wherein each line source serial test by the light-emitting diode (LED) backlight module that the series connection of a plurality of light emitting diodes forms, described test structure comprises:
One direct current power module, this DC power supplier is connected with this light-emitting diode (LED) backlight module;
One control module, and this control module is connected with this DC power supplier; And
A plurality of electronic loads, wherein each electronic load is connected to the end of this line source serial, and is connected with this control module; Wherein, the impedance of the sub-load of this control module adjustable variable.
Wherein the output voltage of this DC power supplier is by this control module control.
Wherein this control module is one to comprise the control unit circuit of a microcontroller.
Wherein this control module is one to comprise the control unit circuit of a microprocessor.
Wherein this control module is one to comprise the control unit circuit of system single chip.
Wherein this electronic load is the modulation circuit with modulation loading functional, and described modulation circuit comprises at least one field effect transistor.
Wherein this electronic load is the modulation circuit with modulation loading functional, and described modulation circuit comprises at least one MOS field-effect transistor.
The utility model overcomes the deficiencies in the prior art, the test structure of the LED-backlit module that provides, but the cooperated with LED backlight module is adjusted size, and bigger measuring current scope is provided, and adjusts the size of current of each LED and not influenced by general control circuit response speed of flowing through; The sub-loaded impedance of control module adjustable variable wherein to reach the purpose of the size of current of adjusting each line source serial, can provide bigger current-responsive scope, and the output of more stable electric current.But the holding circuit response speed has lower ripple current simultaneously.
Description of drawings
Fig. 1 is the PWM waveform of LED-backlit module testing framework of the prior art;
Fig. 2 is the LED-backlit module testing Organization Chart that the utility model embodiment provides.
Embodiment
In order to make the purpose of this utility model, technical scheme and advantage clearer,, the utility model is further elaborated below in conjunction with drawings and Examples.Should be appreciated that specific embodiment described herein only in order to explanation the utility model, and be not used in qualification the utility model.
As shown in Figure 2, the test structure 2 and a LED-backlit module 21 to be measured of the LED-backlit module that provides for the utility model embodiment, this LED-backlit module 21 is to be composed in parallel by a plurality of line source serials 211, and each line source serial 211 is in series by unfixed a plurality of LED2111; One direct current power module 22 is wherein arranged, and this DC power supplier 22 is connected with this LED-backlit module 21; Other has a control module (Control Unit) 23, and this control module 23 is connected with DC power supplier 22; And a plurality of electronic loads 24, wherein each electronic load 24 is connected to the end of above-mentioned line source serial 211, and is connected with this control module 23; Wherein, the impedance of the sub-load 24 of these control module 23 adjustable variables.
The test structure 2 of the LED-backlit module that the utility model embodiment provides utilizes this DC power supplier 22, supplies with this LED-backlit module 21 direct supplys (Idc), makes it can form back light, and the responding range of measuring current can be not limited because of circuit.
Wherein, this LED-backlit module 21 is by m line source serial 211 parallel connections, and each line source serial 211 is in series by unfixed a plurality of LED2111, promptly the 1st is serial to the m serial and is connected in series n LED respectively; First LED resistance value of its first serial is R11, and second LED resistance value is R12, by that analogy, so n LED resistance value is R1n; In like manner, first LED resistance value of m serial is Rm1, and second LED resistance value is Rm2, by that analogy, so n LED resistance value is Rmn; Yet the test structure 2 of the LED-backlit module that the utility model provides can be connected in series the not LED2111 of fixed qty according to need in each line source serial 211.
Connect an electronic load 24 respectively at each line source serial 211 end.This control module 23 then is connected in this DC power supplier 22 and controls its output voltage (Vdc-out), and connect the electronic load 24 of each line source serial 211 end respectively, with its resistance value of modulation (Z), the resistance value that is serial to the m serial of winning is respectively Z1, Z2 ... Zm, to utilize the size of these control module 23 each electronic loads 24 of change, adjust the current value of each line source serial 211.
Its method is for utilizing this DC power supplier 22, supply with this LED-backlit module 21 direct supplys (Idc), make line source serial in parallel 211 get a magnitude of voltage (VLED), the first serial magnitude of voltage (VLED1), the second serial magnitude of voltage (VLED2) ..., m serial magnitude of voltage (VLEDm), the voltage of parallel circuit
VLED＝VLED1＝VLED2＝…＝VLEDm
The electric current of each line source serial 211 be respectively the first serial current value (Idc1), the second serial current value (Idc2) ..., m serial current value (Idcm), wherein, according to ohm theorem,
Idc1＝VLED/(R11+R12+…+R1n+Z1)
Idc2＝VLED/(R21+R22+…+R2n+Z2)
Idcm＝VLED/(Rm1+Rm2+…+Rmn+Zm)
Resistance value Z1, the Z2 of each electronic load 24 of i.e. utilization change ... Zm just can make each line source serial 211 obtain different current values.
Concrete when using the technical scheme that the utility model provides, this control module 23 can adopt a control unit circuit that comprises microcontroller, microprocessor or system single chip; This electronic load 24 is for having the modulation circuit of modulation loading functional, and this modulation circuit comprises at least one field effect transistor or at least one MOS field-effect transistor.
This case because the type of drive of this LED-backlit module 21 is controlled the mode of electronic loads 24 for utilizing DC power supplier 22 and control module 23, has following characteristic compared with the prior art:
The range of adjustment that bigger measuring current is arranged; The uncontrolled influence circuit of response speed; Control the resistance value of electronic load 24, can change the electric current of the LED2111 that flows through; Can cooperated with LED backlight module 21 adjust sizes, change the quantity of LED in the columns of line source serial 211 and the line source serial 211, only must control the resistance value of each electronic load 34, must not redesign circuit.
As mentioned above, the test structure of the LED-backlit module that the utility model provides, but the cooperated with LED backlight module is adjusted size, and bigger measuring current scope is provided, and adjusts the size of current of each LED and not influenced by general control circuit response speed of flowing through; The sub-loaded impedance of control module adjustable variable wherein to reach the purpose of the size of current of adjusting each line source serial, can provide bigger current-responsive scope, and the output of more stable electric current.But the holding circuit response speed has lower ripple current simultaneously.
The above only is preferred embodiment of the present utility model; not in order to restriction the utility model; all any modifications of within spirit of the present utility model and principle, being done, be equal to and replace and improvement etc., all should be included within the protection domain of the present utility model.
Claims (7)
1, a kind of test structure of light-emitting diode (LED) backlight module, be used for to compose in parallel by a plurality of line source serials and wherein each line source serial test by the light-emitting diode (LED) backlight module that the series connection of a plurality of light emitting diodes forms, described test structure comprises:
One direct current power module, this DC power supplier is connected with this light-emitting diode (LED) backlight module;
One control module, and this control module is connected with this DC power supplier; And
A plurality of electronic loads, wherein each electronic load is connected to the end of this line source serial, and is connected with this control module; Wherein, the impedance of the sub-load of this control module adjustable variable.
2, test structure according to claim 1 is characterized in that, wherein the output voltage of this DC power supplier is by this control module control.
3, test structure according to claim 1 is characterized in that, wherein this control module is one to comprise the control unit circuit of a microcontroller.
4, test structure according to claim 1 is characterized in that, wherein this control module is one to comprise the control unit circuit of a microprocessor.
5, test structure according to claim 1 is characterized in that, wherein this control module is one to comprise the control unit circuit of system single chip.
6, test structure according to claim 1 is characterized in that, wherein this electronic load is the modulation circuit with modulation loading functional, and described modulation circuit comprises at least one field effect transistor.
7, test structure according to claim 1 is characterized in that, wherein this electronic load is the modulation circuit with modulation loading functional, and described modulation circuit comprises at least one MOS field-effect transistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200820235214 CN201327518Y (en) | 2008-12-17 | 2008-12-17 | Testing configuration for a light emitting diode backlight module |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200820235214 CN201327518Y (en) | 2008-12-17 | 2008-12-17 | Testing configuration for a light emitting diode backlight module |
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| Publication Number | Publication Date |
|---|---|
| CN201327518Y true CN201327518Y (en) | 2009-10-14 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 200820235214 Expired - Fee Related CN201327518Y (en) | 2008-12-17 | 2008-12-17 | Testing configuration for a light emitting diode backlight module |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102692592A (en) * | 2011-03-22 | 2012-09-26 | 展晶科技(深圳)有限公司 | Method for testing light emitting diode (LED) and LED sectional material used in method |
| WO2013189091A1 (en) * | 2012-06-21 | 2013-12-27 | 深圳市华星光电技术有限公司 | Backlight drive circuit, liquid crystal display module, and manufacturing method thereof |
-
2008
- 2008-12-17 CN CN 200820235214 patent/CN201327518Y/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102692592A (en) * | 2011-03-22 | 2012-09-26 | 展晶科技(深圳)有限公司 | Method for testing light emitting diode (LED) and LED sectional material used in method |
| CN102692592B (en) * | 2011-03-22 | 2014-08-27 | 展晶科技(深圳)有限公司 | Method for testing light emitting diode (LED) and LED sectional material used in method |
| WO2013189091A1 (en) * | 2012-06-21 | 2013-12-27 | 深圳市华星光电技术有限公司 | Backlight drive circuit, liquid crystal display module, and manufacturing method thereof |
| US8890415B2 (en) | 2012-06-21 | 2014-11-18 | Shenzhen China Star Optoelectronics Technology Co., Ltd. | Backlight driving circuit, LCD module, and manufacturing method thereof |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20091014 Termination date: 20161217 |
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| CF01 | Termination of patent right due to non-payment of annual fee |