CN106841993B - A kind of LCD detection device and method - Google Patents
A kind of LCD detection device and method Download PDFInfo
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- CN106841993B CN106841993B CN201710084766.6A CN201710084766A CN106841993B CN 106841993 B CN106841993 B CN 106841993B CN 201710084766 A CN201710084766 A CN 201710084766A CN 106841993 B CN106841993 B CN 106841993B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/282—Testing of electronic circuits specially adapted for particular applications not provided for elsewhere
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Liquid Crystal Display Device Control (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
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Abstract
The present invention discloses a kind of LCD detection device and method, and detection device includes the column signal comparator that an input terminal row signal comparator, the input terminal that connect with LCD driving plate row signal output end are connect with LCD driving plate column signal output end；The row signal comparator, column signal comparator output end connect with processor；Another input terminal of the row signal comparator is connect with row signal voltage selecting module；Another input terminal of the column signal comparator is connect with column signal voltage selection module；The row signal voltage selecting module, column signal voltage selection module are connect with the power output end of LCD driving plate；The row signal voltage selecting module, column signal voltage selection module output end be connected to the processor.Hardware cost of the present invention is low, low to site environment requirement, and testing result is accurate and reliable.
Description
Technical field
The present invention relates to board detection field, especially a kind of LCD detection device and method are particularly suitable for monochromatic LCD
The detection of screen.
Background technique
Video driver and master control are needed in the remote controler with LCD display function of electrical equipment, in order to reduce cost, remote control
Video driver and master control are integrated on chip piece by device business men, and by the chip attachment on PCB, so that PCB and chip one
Secondary molding needs in the pre-assembly, to detect PCB to improve assembly yield, reduces failure rate.Existing detection
Method is powered to PCB, then connect it with remote controler, the display pattern of LCD is obtained by camera, and to the figure of acquisition
Picture is identified whether the process for observing display is correct using image-recognizing method, judges whether PCB is qualified.This method is to existing
Field environmental requirement is stringent, for example PCB must be static, and camera imaging must be clear, cannot there is foreign matter on camera, and LCD cannot
It is reflective, light to guarantee it is bright etc., in addition, the quality of imaging position, image-recognizing method can generate direct shadow to testing result
It rings, and the hardware cost of this method is higher (such as camera, camera lens are expensive).
Summary of the invention
The technical problem to be solved by the present invention is in view of the shortcomings of the prior art, provide a kind of LCD detection device and side
Method.
In order to solve the above technical problems, the technical scheme adopted by the invention is that: a kind of LCD detection device, including one
Row signal comparator, an input terminal and the LCD driving plate column signal that input terminal is connect with LCD driving plate row signal output end are defeated
The column signal comparator of outlet connection；The row signal comparator, column signal comparator output end connect with processor；Institute
Another input terminal for stating row signal comparator is connect with row signal voltage selecting module；The column signal comparator is in addition
One input terminal is connect with column signal voltage selection module；The row signal voltage selecting module, column signal voltage selection module
It is connect with the power output end of LCD driving plate；The output of row the signal voltage selecting module, column signal voltage selection module
End is connected to the processor.
The row signal comparator, column signal comparator output end pass through pull-up resistor and connect processor power supply.
The row signal voltage selecting module is in parallel with indicator light.
The row signal voltage selecting module includes the first analog switch；The first input end of first analog switch is logical
Cross the power output end that first resistor connects the LCD driving plate；Second input terminal of first analog switch passes through the second electricity
Resistance connects the power output end of the LCD driving plate；The second resistance is connected with 3rd resistor, the 4th resistance；First mould
The third input terminal of quasi- switch accesses between the second resistance and the 3rd resistor；The 4th of first analog switch is defeated
Enter to terminate between the 3rd resistor and the 4th resistance；The 4th resistance other end ground connection；First simulation is opened
The remaining input terminal of pass is grounded；The control output end of first analog switch connects the processor；First analog switch
Public output connect the positive input terminal of first voltage follower；The output of the first voltage follower terminates the row signal
The negative input end of comparator.
The column signal voltage selection module includes the second analog switch；The first input end of second analog switch is logical
Cross the power output end that first resistor connects the LCD driving plate；Second input terminal of second analog switch passes through the second electricity
Resistance connects the power output end of the LCD driving plate；The second resistance is connected with 3rd resistor, the 4th resistance；Second mould
The third input terminal of quasi- switch accesses between the second resistance and the 3rd resistor；The 4th of second analog switch is defeated
Enter to terminate between the 3rd resistor and the 4th resistance；The 4th resistance other end ground connection；Second simulation is opened
The remaining input terminal of pass is grounded；The control output end of second analog switch connects the processor；Second analog switch
Public output connect the positive input terminal of second voltage follower；The output of the second voltage follower terminates the column row letter
The negative input end of number comparator.
The LCD driving plate includes 4 row signal output ends and 32 column signal output ends.
Correspondingly, the present invention also provides a kind of method using above-mentioned detection device detection LCD, this method includes following
Step:
1) row signal comparator external reference voltage is adjusted are as follows: REF_COM=VH, REF_SEG=VL wait external ginseng
After examining voltage stabilization, the level state of row signal, i.e. COM state are read in timing, after debounce processing if COM is high level
Think that corresponding row exists, and record and be expert in state table, while recording line number at this time；It is continuously read by a period of time T
COM level determines COM state and scanning sequency；REF_COM is the external reference voltage of row signal comparator；VH is LCD drive
The minimum voltage value of high level in movable plate；REF_SEG is the external reference voltage of column signal comparator；VL is in LCD driving plate
Low level maximum voltage value；
2) entering COM level is height mode, starts to detect according to row state table, after the completion of all rows detect,
It is low mode into COM level, is sampled by stablizing for N number of period, obtain stable position state table；Wherein, COM level is height
Then recording SEG is low level position: external reference voltage being first adjusted to REF_COM=VH, REF_SEG=VL, is waited external
Reference voltage stablize after periodically read SEG state, think if SEG is low level after debounce processing this state be it is bright,
Set bit state table simultaneously；COM level be it is low, recording SEG is high level position, and external reference voltage is first adjusted to REF_
COM=VL, REF_SEG=VH periodically read SEG state after waiting external reference voltage to stablize, if SEG after debounce processing
Then think that this state is bright, while Set bit state table for high level；SEG is column signal；
3) the stable position state table and mask obtained step 2 carries out step-by-step and calculates, and obtains LCD and shows position state
Table；
1) it reads LCD and shows position state table, then compared with preset display state table, then think that test is closed if they are the same
Lattice think test failure if variant.
In the present invention, T is set as 200 times of scan period, and N is 3~5.
Compared with prior art, the advantageous effect of present invention is that: hardware cost of the present invention is low, wants to site environment
Ask low, testing result is accurate and reliable.
Detailed description of the invention
Fig. 1 is LCD of embodiment of the present invention driving plate interface schema；
Fig. 2 is COM0 of the embodiment of the present invention and comparator catenation principle figure；
Fig. 3 is SEG0 of the embodiment of the present invention and comparator catenation principle figure；
Fig. 4 is voltage selection module of embodiment of the present invention schematic diagram；
Fig. 5 is Fundamentals of Mono-Chip Computers figure of the present invention；
Fig. 6 is indicator light partial schematic diagram of the present invention.
Specific embodiment
As shown in Fig. 1~Fig. 6, LCD driving plate is defeated including four row signal output ends (COM0~COM4), 32 column signals
Outlet (SEG0~SEG31), each row signal output end connect (such as COM0 with the positive input terminal of a row signal comparator
It is connect with the positive input terminal of comparator U4A), each column signal output end is connect with the positive input terminal of a column signal comparator
(such as SEG0 is connect with the positive input terminal of comparator U5A)；The row signal comparator, column signal comparator output end with
Processor (single chip computer AT mega64) connection；Another input terminal and row signal voltage of the row signal comparator select mould
Block connection；Another input terminal of the column signal comparator is connect with column signal voltage selection module；The row signal electricity
Pressure selecting module, column signal voltage selection module are connect with the power output end of LCD driving plate；The row signal voltage selection
Module, column signal voltage selection module output end be connected to the processor.COM4 is the 4th row signal output end；
SEG31 is the 32nd column signal output end.
The row signal comparator, column signal comparator output end pass through pull-up resistor and connect processor power supply, for example,
In Fig. 2, the output end DCOM0 of row signal comparator meets microcontroller power supply VDD by pull-up resistor R46.
The row signal voltage selecting module (see figure 6) in parallel with indicator light D1.
As shown in fig. 6, the row signal voltage selecting module includes the first analog switch U3；First analog switch
First input end CH0 meets the power output end VCLD of the LCD driving plate by first resistor R1；First analog switch
Second input terminal CH1 connects the power output end of the LCD driving plate by second resistance R2；The second resistance and 3rd resistor
R4, the 4th resistance R8 series connection；The third input terminal CH2 of first analog switch accesses the second resistance and third electricity
Between resistance；4th input terminal CH3 of first analog switch is accessed between the 3rd resistor and the 4th resistance；It is described
The 4th resistance other end is grounded GND；The remaining input terminal (CH4, CH5, CH6, CH7) of first analog switch is grounded；It is described
Control output end A0, A1, A2 of first analog switch connect the processor；The public output COM of first analog switch
Connect the positive input terminal of first voltage follower U1A；The output of the first voltage follower terminates the row signal comparator
Negative input end.
As shown in fig. 6, the column signal voltage selection module includes the second analog switch U2；Second analog switch
First input end connects the power output end of the LCD driving plate by first resistor；Second input of second analog switch
End connects the power output end of the LCD driving plate by second resistance；The second resistance and 3rd resistor, the 4th resistance string
Connection；The third input terminal of second analog switch accesses between the second resistance and the 3rd resistor；Second mould
4th input terminal of quasi- switch accesses between the 3rd resistor and the 4th resistance；The 4th resistance other end ground connection；
The remaining input terminal of second analog switch is grounded；The control output end of second analog switch connects the processor；Institute
The public output for stating the second analog switch connects the positive input terminal of second voltage follower U1B；The second voltage follower
Output terminates the negative input end of the column row signal comparator.
External reference voltage can export four kinds of different voltages values (can adjust out the electricity needed by adjusting divider resistance
Pressure value), when detecting high level, reference voltage should select to be not less than high level minimum voltage value (VH) in LCD driving plate, when
Reference voltage should be selected not higher than low level maximum voltage value (VL) in LCD driving plate, the tool of VH and VL when detecting low level
Bulk voltage value is defined by LCD driving plate level to be checked and is determined.
Detection starts, and LCD driving plate driving signal to be measured is connected to the input terminal of detection device by external tooling.Industrial personal computer hair
To detection device, detection device creates a position state table first for starting sense command out (for storing all status informations)
With a row state table (for recording effective row information), and emptied.It scans LCD and shows method there are many states, here
Selection is with behavior master, the method for reading column-shaped state.
It is positive and the scanning LCD of sequence is truly had to show state, it should determine effective number of lines and row scan sequence first, this process
Referred to as " scanning learning ".First external reference voltage is adjusted before study are as follows: REF_COM=VH, REF_SEG=VL are waited external
Opening timing reads COM state (i.e. the state of DCOM0~DCOM3) after reference voltage is stablized, if COM is after debounce processing
High level then thinks that this journey exists, and records and be expert in state table, while recording line number at this time.By a period of time, (this is
Learning time can adjust accordingly according to drive characteristic, usually 200 of scan period times or so) COM level is read, really
It sets COM state and scanning sequency can be carried out column scan.
Certain LCD sections is lighted and have two ways by LCD driving signal: COM level is that high SEG level is low；COM electricity
It is high for putting down as low SEG level.LCD display residual is formed by curing since the long-term fixed-direction pressure difference of liquid crystal will lead to liquid crystal molecule
(ghost) influences display effect, and LCD driving signal can carry out in turn above two lighting mode (general a line-scanning period
Switch a lighting mode afterwards), avoid liquid crystal from generating long-term fixed-direction pressure difference.According to the characteristic column scan of LCD driving signal
Also there are two types of scan patterns: COM level is height mode and COM level is low mode.COM level is that height then detects SEG low level
Position: first external reference voltage is adjusted are as follows: REF_COM=VH, REF_SEG=VL, timing after waiting external reference voltage to stablize
It reads SEG state (i.e. the state of SEG0~SEG31), thinks that this state is if SEG is low level after debounce processing
It is bright, while Set bit state table；COM level be it is low, detect SEG high level position: being first adjusted to external reference voltage; REF_
COM=VL, REF_SEG=VH periodically read SEG state after waiting external reference voltage to stablize, if SEG after debounce processing
Then think that this state is bright, while Set bit state table for high level.Column scan initially enters COM level after starting be Gao Mo
Formula starts to detect according to row state table, is low mode into COM level after the completion of all rows detect.Pass through 3 ~ 5
A period stablizes sampling, obtains stable position state table.
LCD display will not use up all position information of driver (it is reserved to do part) under normal circumstances, in order to react
The true display situation of LCD screen needs alignment table to carry out mask calculating, deletes reserved position state, and mask is actual use
Position truth table.Mask for calculating needs external program to deposit into the memory of detection device in advance, and detection device obtains shape in place
It is carried out step-by-step with mask and calculated by state table, is obtained LCD and is shown that position state table, this table are inquired for external program.
Industrial personal computer reads LCD by serial communication and shows position state table, then compares with the preset display state table of software,
Test passes are then thought if they are the same, test failure is thought if variant, and so far this driving plate detection is completed, and can be switched
Awaiting board card.
Claims (3)
1. a kind of method for detecting LCD realizes that LCD is detected using LCD detection device, the LCD detection device includes one defeated
Enter row signal comparator, an input terminal and LCD driving plate column signal that end is connect with LCD driving plate row signal output end to export
Hold the column signal comparator of connection；The row signal comparator, column signal comparator output end connect with processor；It is described
Another input terminal of row signal comparator is connect with row signal voltage selecting module；Other the one of the column signal comparator
A input terminal is connect with column signal voltage selection module；The row signal voltage selecting module, column signal voltage selection module are equal
It is connect with the power output end of LCD driving plate；The output end of the row signal voltage selecting module, column signal voltage selection module
It is connected to the processor；It is characterized in that, method includes the following steps:
1) row signal comparator external reference voltage is adjusted are as follows: REF_COM=VH, REF_SEG=VL wait external reference electricity
After pressure is stablized, the level state of row signal, i.e. COM state are read in timing, are thought if COM is high level after debounce processing
Corresponding row exists, and records and be expert in state table, while recording line number at this time；COM electricity is continuously read by a period of time T
It is flat, determine COM state and scanning sequency；REF_COM is the external reference voltage of row signal comparator；VH is LCD driving plate
The minimum voltage value of middle high level；REF_SEG is the external reference voltage of column signal comparator；VL is low electricity in LCD driving plate
Flat maximum voltage value；
2) entering COM level is height mode, starts to detect according to row state table, after the completion of all rows detect, is entered
COM level is low mode, is sampled by stablizing for N number of period, obtains stable position state table；Wherein, COM level is Gao Zeji
Record SEG is low level position: external reference voltage being first adjusted to REF_COM=VH, REF_SEG=VL, waits external reference
SEG state is periodically read after voltage stabilization, think if SEG is low level after debounce processing this state be it is bright, simultaneously
Set bit state table；COM level be it is low, recording SEG is high level position, first by external reference voltage be adjusted to REF_COM=
VL, REF_SEG=VH periodically read SEG state after waiting external reference voltage to stablize, if SEG is high electricity after debounce processing
It is flat then think that this state is bright, while Set bit state table；SEG is column signal；
3) the stable position state table and mask obtained step 2 carries out step-by-step and calculates, and obtains LCD and shows position state table；
4) it reads LCD and shows position state table, then compared with preset display state table, then think test passes if they are the same, if
It is variant, think test failure.
2. the method according to claim 1, wherein T is set as 200 times of scan period.
3. the method according to claim 1, wherein N is 3~5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710084766.6A CN106841993B (en) | 2017-02-16 | 2017-02-16 | A kind of LCD detection device and method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710084766.6A CN106841993B (en) | 2017-02-16 | 2017-02-16 | A kind of LCD detection device and method |
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| CN106841993A CN106841993A (en) | 2017-06-13 |
| CN106841993B true CN106841993B (en) | 2019-09-06 |
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| CN109239993B (en) * | 2018-10-18 | 2021-03-26 | 华北水利水电大学 | Liquid crystal optical switch for optical phased array scanning |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6535011B1 (en) * | 1999-07-23 | 2003-03-18 | Sharp Kabushiki Kaisha | Testing device and testing method for a semiconductor integrated circuit and storage medium having the testing program stored therein |
| CN1467699A (en) * | 2002-06-21 | 2004-01-14 | 奇景光电股份有限公司 | Method and related apparatus for driving an lcd monitor |
| EP1858028A1 (en) * | 2006-05-18 | 2007-11-21 | Dialog Semiconductor GmbH | Memory test engine |
| CN101556757A (en) * | 2008-04-10 | 2009-10-14 | 奇景光电股份有限公司 | Test circuit of display driving circuit |
-
2017
- 2017-02-16 CN CN201710084766.6A patent/CN106841993B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6535011B1 (en) * | 1999-07-23 | 2003-03-18 | Sharp Kabushiki Kaisha | Testing device and testing method for a semiconductor integrated circuit and storage medium having the testing program stored therein |
| CN1467699A (en) * | 2002-06-21 | 2004-01-14 | 奇景光电股份有限公司 | Method and related apparatus for driving an lcd monitor |
| EP1858028A1 (en) * | 2006-05-18 | 2007-11-21 | Dialog Semiconductor GmbH | Memory test engine |
| CN101556757A (en) * | 2008-04-10 | 2009-10-14 | 奇景光电股份有限公司 | Test circuit of display driving circuit |
Non-Patent Citations (1)
| Title |
|---|
| 一个通用LCD 驱动电路设计;汪艳彬等;《电子器件》;20081231;第31卷(第6期);第1730-1734页 |
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