CN108735153B - Micro-display pixel circuit with body driving structure - Google Patents

Micro-display pixel circuit with body driving structure Download PDF

Info

Publication number
CN108735153B
CN108735153B CN201810548571.7A CN201810548571A CN108735153B CN 108735153 B CN108735153 B CN 108735153B CN 201810548571 A CN201810548571 A CN 201810548571A CN 108735153 B CN108735153 B CN 108735153B
Authority
CN
China
Prior art keywords
transistor
pixel circuit
stage
drive
electrode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810548571.7A
Other languages
Chinese (zh)
Other versions
CN108735153A (en
Inventor
李洪革
卢汇源
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beihang University
Original Assignee
Beihang University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beihang University filed Critical Beihang University
Publication of CN108735153A publication Critical patent/CN108735153A/en
Application granted granted Critical
Publication of CN108735153B publication Critical patent/CN108735153B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0271—Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
  • Electroluminescent Light Sources (AREA)
  • Control Of El Displays (AREA)

Abstract

The application discloses little display pixel circuit of body drive structure has solved the little problem of pixel circuit input data voltage range among the current OLEDoS microdisplay. The pixel circuit comprises a switch stage, an intermediate stage and a light-emitting stage, wherein the switch stage is connected with the intermediate stage, the intermediate stage is connected with the light-emitting stage, the switch stage comprises a switch transistor, the intermediate stage comprises a first adjusting transistor, a second adjusting transistor and a storage capacitor, the light-emitting stage comprises a driving transistor and a light-emitting diode, the switch stage transmits voltage to the intermediate stage in the working process of the circuit, and the voltage is adjusted by the intermediate stage and is transmitted to the light-emitting stage after the width range of the voltage is enlarged. The pixel circuit provided by the application can widen the input range of data voltage, and further realizes higher gray scale, high precision and high quality display.

Description

Micro-display pixel circuit with body driving structure
Technical Field
The application relates to the technical field of micro display, in particular to a pixel circuit of a volume driving structure.
Background
The application scenes of micro-display are increasing in recent years, such as smart glasses, virtual reality glasses and the like, which also promotes the further development of micro-display technology. The OLEDoS technology is one of important solutions in micro display, has the advantages of self luminescence of an Organic Light Emitting Diode (OLED), high response speed, simple preparation process, mature silicon process technology, high reliability and the like, and has wide application prospect. Products applying the OLEDoS technology to military head-mounted display equipment and the field of virtual reality display have appeared abroad, and domestic corresponding research and industrialization are relatively slow to advance. In the OLED os microdisplay, the pixel circuit directly controls the luminance of the OLED light according to a data driving signal provided by a previous source driver, which determines the quality of the screen display, and is one of the most important parts of the entire microdisplay. Pixel circuits applied to microdisplays face more stringent requirements than pixel circuits in large-screen displays: the micro-display pixel circuit can achieve a narrower data voltage range, a smaller light emitting current for the OLED, a smaller area occupied by a single pixel circuit, and the like.
In the currently commonly used micro-display pixel circuit, the width of the input data voltage range generally does not exceed 1V, and the ratio of the data voltage width to the power supply voltage generally does not exceed 50%. And the feasibility of realizing high gray scale and high image quality by micro-display is restricted. Therefore, the invention provides a micro-display pixel circuit with a bulk drive structure, which solves the problems in the prior art, can widen the input range of data voltage, and further realizes higher gray scale, high precision and high quality display.
Disclosure of Invention
The embodiment of the application provides a volume drive structure micro-display pixel circuit, which solves the problem that the gray scale and the precision of the existing OLEDoS micro-display technology are limited by the input range of data voltage.
The embodiment of the application provides a micro-display pixel circuit with a body driving structure, which comprises a switch stage, a light-emitting stage and an intermediate stage; the switching stage comprises a switching transistor; the light emitting stage comprises a driving transistor and a light emitting diode;
the intermediate stage comprises a first regulating transistor, a second regulating transistor and a storage capacitor;
the grid electrode of the switch transistor is connected with a scanning signal, the source electrode of the switch transistor is connected with a data driving signal, and the drain electrode of the switch transistor is connected with the grid electrode of the first adjusting transistor;
the source electrode of the first regulating transistor is connected with a power supply voltage, and the drain electrode of the first regulating transistor is connected with the source electrode of the second regulating transistor;
the drain electrode of the second regulating transistor is connected with the grid electrode and grounded, and the source electrode of the second regulating transistor is connected with the substrate;
the positive electrode of the storage capacitor is connected with a power supply voltage, and the negative electrode of the storage capacitor is connected with the grid electrode of the first regulating transistor;
the grid electrode of the driving transistor is connected with the source electrode and the cathode electrode of the light emitting diode, and the drain electrode of the driving transistor is grounded;
and the anode of the light-emitting diode is connected with a high voltage of a power supply.
Preferably, the switching transistor, the first regulating transistor, the second regulating transistor and the driving transistor are all P-type metal oxide semiconductor field effect transistors.
Preferably, the drain of the first regulating transistor is connected to the substrate of the driving transistor.
Preferably, the scan signal is a row scan signal, and the scan signal has a high and low continuous voltage signal, wherein the low level is used for turning on the switching transistor, and the high level is used for turning off the switching transistor.
Preferably, the data driving signal is an analog voltage signal having a stable value.
Preferably, the scan signal is provided by a gate driver, and the data driving signal is provided by a source driver.
Preferably, the source driver includes a digital part, a level conversion part, a digital-to-analog conversion part, and an output buffer part, which are sequentially connected.
Preferably, the digital-to-analog conversion section includes a gamma correction circuit and a level selection circuit;
the gamma correction circuit is used for leading out the data voltage in a two-pole voltage division mode;
the level selection circuit is used for selecting digital voltage according to an external digital signal.
At least one embodiment of the present application has the following advantageous effects:
the input range of the data voltage can be widened, and higher gray scale and high-precision and high-quality display can be realized.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:
fig. 1 is a circuit diagram of a micro display pixel circuit with a bulk driving structure according to an embodiment of the present disclosure;
FIG. 2 is a schematic diagram of an array on a micro-display pixel circuit panel with a bulk-drive structure according to an embodiment of the present disclosure;
fig. 3 is a schematic diagram of a source driving structure of a micro display pixel circuit with a bulk driving structure according to an embodiment of the present disclosure;
fig. 4 is a signal timing diagram of a micro display pixel circuit with a bulk driving structure according to an embodiment of the present disclosure.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail and completely with reference to the following specific embodiments of the present application and the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Fig. 1 is a block diagram of a micro display pixel circuit with a bulk driving structure according to an embodiment of the present disclosure, which includes a switching stage, an intermediate stage, and a light emitting stage; the switching stage comprises a switching transistor M1; the middle stage includes a first adjusting transistor M2, a second adjusting transistor M3, and a storage capacitor Cst; the light emitting stage comprises a driving transistor M4 and a light emitting diode OLED; the grid electrode of the switch transistor is connected with a scanning signal Vscan, the source electrode of the switch transistor is connected with a data driving signal Vdata, and the drain electrode of the switch transistor is connected with the grid electrode of the first adjusting transistor; the source electrode of the first regulating transistor is connected with a power supply voltage VDD, and the drain electrode of the first regulating transistor is connected with the source electrode of the second regulating transistor; the drain electrode of the second regulating transistor is connected with the grid electrode and grounded, and the source electrode of the second regulating transistor is connected with the substrate; the positive electrode of the storage capacitor is connected with a power supply voltage, and the negative electrode of the storage capacitor is connected with the grid electrode of the first regulating transistor; the grid electrode of the driving transistor is connected with the source electrode and the cathode electrode of the light emitting diode, and the drain electrode of the driving transistor is grounded; and the anode of the light emitting diode is connected with a power supply high voltage VDDH. The driving transistor is connected in a body driving mode, the drain electrode of the first adjusting transistor is connected with the substrate of the driving transistor, and data voltage in the driving transistor changes substrate voltage through substrate input, so that the threshold voltage of the driving transistor and the light emitting current of the light emitting diode are changed.
In one embodiment of the present application, the switching transistor, the first regulating transistor, the second regulating transistor, and the driving transistor are all P-type metal oxide semiconductor field effect transistors. When the body driving structure micro-display pixel circuit works, the scanning signal and the data driving signal control the switching transistor to be started, meanwhile, the data voltage charges the storage capacitor, the voltage stored in the storage capacitor is adjusted through the first adjusting transistor and the second adjusting transistor, the voltage is transmitted to the driving transistor after the width range of the voltage is increased, the driving transistor adjusts the data voltage range and generates corresponding light-emitting current, and the light-emitting diode OLED is lightened.
Fig. 2 is a schematic diagram of an array on a circuit panel of a micro display pixel with a bulk driving structure according to an embodiment of the present disclosure, as shown in fig. 2, the scan signal is provided by gate driving, and the data driving signal is provided by source driving, where the scan signal is a row scan signal, and has a high-low two-level sustain voltage signal, the low level is used for turning on the switching transistor, the high level is used for turning off the switching transistor, and the duration of the high level signal is longer than that of the low level signal. The data driving signal is an analog voltage signal with a plurality of stable values, the data driving signal which needs to be read in before the switching transistor is started is correct and stable, and the data voltage signal is still correct and stable within a period of time after the switching transistor is turned off.
Fig. 3 is a schematic diagram of a source driving structure of a micro-display pixel circuit with a bulk driving structure according to an embodiment of the present disclosure, and as shown in fig. 3, a basic structure of the source driving includes a digital portion, a level conversion portion, a digital-to-analog conversion portion, and an output buffer portion, which are sequentially connected. The digital part is used for generating various digital logic signals required by source electrode driving, and a low-level transistor is adopted in physical realization; the level conversion part is used for converting the logic signal level generated by the digital part into a higher logic level required by a subsequent structure; the digital-to-analog conversion part comprises a gamma correction circuit and a level selection circuit, and is used for converting digital logic signals into corresponding analog level signals, wherein the gamma correction circuit is used for leading out data voltages in a bipolar voltage division mode, and the level selection circuit is used for selecting digital voltages according to external digital signals; the output buffer part is used for stabilizing the data voltage signal generated by the preceding stage circuit and improving the loading capacity of the source electrode drive.
The externally supplied digital signal is converted through the structure into an analog voltage signal required to drive the structured microdisplay pixel circuit.
Fig. 4 is a signal timing diagram of a micro display pixel circuit with a bulk driving structure according to an embodiment of the present disclosure, and as shown in fig. 4, a working period C of the micro display pixel circuit with the bulk driving structure includes a reading-in stage a and a light-emitting stage B, and the working period is continuously cycled.
In the read-in phase a, it is first ensured that the data driving signal is correct and stable, when the scan signal is at a low level, the switching transistor is turned on, the data driving signal reads in the stable signal, and the data voltage charges the storage capacitor through the switching transistor.
In the light emitting stage B, the data voltage stored in the storage capacitor is adjusted by the first adjusting transistor and the second adjusting transistor to make the width range reach a predetermined value, and transmitted to the substrate of the driving transistor in the light emitting stage, and the driving transistor adjusts the data voltage range and generates a corresponding current to light the light emitting diode.
Let the connection point of the drain of the switching transistor M1 and the gate of the first regulating transistor M2 be P point, and the connection point of the drain of the first regulating transistor M2 and the source of the second regulating transistor M3 be Q point. Specifically, the principle that the first adjusting transistor and the second adjusting transistor adjust the data voltage width range is as follows:
under the condition that the first regulating transistor and the second regulating transistor work in saturation, the leakage currents are respectively as follows:
a first regulating transistor:
Figure BDA0001680548710000051
μ is the carrier mobility, C, of transistor M2OXCapacitance per unit area of gate insulating layer of transistor M2 (W/L)2Channel width to length ratio, V, of M2PIs a voltage at point P, VM2,THIs the threshold voltage of M2.
A second regulating transistor:
Figure BDA0001680548710000052
where μ is the carrier mobility of transistor M3 and COX is the gate insulator capacitance per unit area of transistor M3, (W/L)3The channel width to length ratio of M3, VQ the Q-point voltage, VM3, TH the threshold voltage of M3.
Since the leakage currents of the first and second regulating transistors are the same, it can be obtained according to the above formula:
Figure BDA0001680548710000061
the following conclusions can be drawn from the above formula: only k needs to be guaranteed2Less than k3That is, the width-to-length ratio of M2 is smaller than the width-to-length ratio of M3, so that it can be ensured that the Q-point voltage variation is smaller than the P-point voltage variation, and the function of expanding the data voltage range required by the Q-point at the P-point is realized.

Claims (10)

1. A micro display pixel circuit with a body driving structure comprises a switch stage and a light emitting stage; the switching stage comprises a switching transistor; the light emitting stage comprises a driving transistor and a light emitting diode; it is characterized by also comprising an intermediate stage;
the intermediate stage comprises a first regulating transistor, a second regulating transistor and a storage capacitor;
the grid electrode of the switch transistor is connected with a scanning signal, the source electrode of the switch transistor is connected with a data driving signal, and the drain electrode of the switch transistor is connected with the grid electrode of the first adjusting transistor;
the source electrode of the first regulating transistor is connected with a power supply voltage, and the drain electrode of the first regulating transistor is connected with the source electrode of the second regulating transistor;
the drain electrode of the second regulating transistor is connected with the grid electrode and grounded, and the source electrode of the second regulating transistor is connected with the substrate;
the positive electrode of the storage capacitor is connected with a power supply voltage, and the negative electrode of the storage capacitor is connected with the grid electrode of the first regulating transistor;
the grid electrode of the driving transistor is connected with the source electrode and the cathode electrode of the light emitting diode, and the drain electrode of the driving transistor is grounded;
the anode of the light emitting diode is connected with a high voltage of a power supply;
the drain electrode of the first adjusting transistor is connected with the substrate of the driving transistor;
the width-to-length ratio of the first regulating transistor is smaller than that of the second regulating transistor.
2. The bulk drive architecture microdisplay pixel circuit of claim 1 in which the switching transistor, first adjusting transistor, second adjusting transistor and drive transistor are all P-type metal oxide semiconductor field effect transistors.
3. The bulk drive architecture microdisplay pixel circuit of claim 1 in which the drain of the first adjusting transistor is connected to the substrate of the drive transistor.
4. The bulk drive architecture microdisplay pixel circuit of claim 1 in which the scan signal is a row scan signal having a sustain voltage signal of two levels, high and low, with low for turning on the switching transistor and high for turning off the switching transistor.
5. The bulk-drive architecture microdisplay pixel circuit of claim 1 in which the data drive signal is an analog voltage signal having a stable value.
6. The bulk drive architecture microdisplay pixel circuit of claim 1 in which the scan signal is provided by gate drive and the data drive signal is provided by source drive.
7. The bulk drive architecture microdisplay pixel circuit of claim 6 in which the source drive comprises a digital section, a level conversion section, a digital to analog conversion section and an output buffer section connected in series.
8. The bulk drive architecture microdisplay pixel circuit of claim 7 in which the digital section is comprised of low level transistors for generating the digital logic signals required for source drive.
9. The bulk drive architecture microdisplay pixel circuit of claim 7 in which the level shifting section is used to shift the low logic signal level generated by the digital section to a high logic signal level required for subsequent architecture.
10. The bulk drive architecture microdisplay pixel circuit of claim 7 in which the digital-to-analog conversion section is used to convert digital logic signals to corresponding analog level signals and the output buffer section is used to increase source drive loading and stabilize data voltage signals.
CN201810548571.7A 2018-04-19 2018-05-31 Micro-display pixel circuit with body driving structure Active CN108735153B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN2018103546129 2018-04-19
CN201810354612 2018-04-19

Publications (2)

Publication Number Publication Date
CN108735153A CN108735153A (en) 2018-11-02
CN108735153B true CN108735153B (en) 2020-06-09

Family

ID=63931504

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810548571.7A Active CN108735153B (en) 2018-04-19 2018-05-31 Micro-display pixel circuit with body driving structure

Country Status (1)

Country Link
CN (1) CN108735153B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109410840A (en) * 2018-11-13 2019-03-01 中国电子科技集团公司第五十五研究所 A kind of silicon substrate micro display pixel circuit of high uniformity Low dark curient
CN111445857B (en) 2020-04-17 2021-05-14 上海天马有机发光显示技术有限公司 Pixel driving circuit, driving method thereof and display device
WO2023039761A1 (en) * 2021-09-15 2023-03-23 京东方科技集团股份有限公司 Display substrate, pixel circuit, driving method, and display device

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101377798B1 (en) * 2007-07-19 2014-03-24 파나소닉 주식회사 image display device
CN101710784B (en) * 2009-12-24 2011-09-07 浙江大学 Charge pump circuit working at extra low voltage
CN102956197B (en) * 2012-10-26 2015-07-01 上海大学 Current pulse width modulation driving circuit of micro display with silicon-based OLED (organic light emitting diode)
CN105304023A (en) * 2015-11-18 2016-02-03 上海大学 Pixel recession compensation circuit of silicon-based organic light emitting micro-display

Also Published As

Publication number Publication date
CN108735153A (en) 2018-11-02

Similar Documents

Publication Publication Date Title
CN113838421B (en) Pixel circuit, driving method thereof and display panel
US20220277695A1 (en) Display panel and method for driving the same, and display device
US11620942B2 (en) Pixel circuit, driving method thereof and display device
US10978002B2 (en) Pixel circuit and driving method thereof, and display panel
CN109671398B (en) Driving method of pixel driving circuit, display panel and display device
US11227548B2 (en) Pixel circuit and display device
CN109801592B (en) Pixel circuit, driving method thereof and display substrate
US11367393B2 (en) Display panel, driving method thereof and display device
CN111179820A (en) Pixel circuit and display panel
CN111223447A (en) Pixel circuit and display panel
CN108735153B (en) Micro-display pixel circuit with body driving structure
US11568815B2 (en) Pixel driving circuit, manufacturing method thereof, and display device
WO2021083014A1 (en) Pixel drive circuit and drive method therefor, display panel, and display apparatus
CN110164375B (en) Pixel compensation circuit, driving method, electroluminescent display panel and display device
CN112767874B (en) Pixel driving circuit, driving method thereof and display panel
CN113450712B (en) Pixel driving device and method of silicon-based light-emitting unit and display panel
CN113077751A (en) Pixel driving circuit, driving method thereof and display panel
CN113593481B (en) Display panel and driving method thereof
WO2022016722A1 (en) Pixel circuit and driving method therefor
CN108550344B (en) Current-type pixel unit circuit applied to self-luminescence, driving current generation method and image or video display method
GB2620507A (en) Pixel circuit and driving method therefor and display panel
JPWO2019159651A1 (en) Pixel circuits, display devices, pixel circuit drive methods and electronic devices
CN115798411A (en) Display panel, driving method thereof and display device
WO2022226727A1 (en) Pixel circuit, pixel driving method and display device
CN114220395A (en) Pixel driving circuit, display panel and driving method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant