CN101154349A - Charge recycling circuit of display device - Google Patents

Abstract

The invention provides a charge recycling circuit of a display device, which is used for connecting a display panel of a display module and a source drive circuit, wherein the display module is provided with the source drive circuit and a gate drive circuit, when the source drive circuit is closed, the circuit recycling circuit can transfer charges to a system external capacitor, the charge recycling circuit comprises a charge transfer circuit, the charge transfer circuit can guide the stored charges of a display panel parasitic capacitor to a system external capacitor element for storage, in addition, a detection switch element is arranged between the charge transfer circuit and the source drive circuit, the detection switch element can detect the voltage between the display panel and a source level drive circuit, and the access state between the charge transfer circuit and the source drive circuit is determined according to the light-emitting critical voltages of different color layer display panels. The invention can effectively save the power of the power supply, thereby increasing the service efficiency of the battery.

Description

Charge Recovery Cycle Circuit for Display Devices

technical field

The invention relates to a circuit structure, in particular to a charge recovery cycle circuit of a display device which saves power and increases battery performance.

Background technique

In recent years, the price of liquid crystal display has fallen rapidly, which has rapidly expanded its application area, which has broken the long-term dominance of CRT and made the whole flat panel display (FPD) full of vitality. Although liquid crystal is the mainstream, emerging technologies have entered the market application stage after continuous research and development, such as plasma display (PDP), low temperature polysilicon (LTPS), rear projection display, etc. Organic light emitting diodes (Organic Light Emitting Diode; OLED) with luminescence (no need for backlight source) and simple structure are the most popular in the consumer market.

And OLED can attract everyone's attention, not only the investment threshold of its production equipment is much lower than that of TFTLCD, but also its product features such as self-emitting color light (no need for backlight, color filter), which can greatly reduce the cost and display module thickness (thin 2mm), and has the advantages of high brightness, no viewing angle limitation (greater than 165 degrees), high response speed (below 10μs), low driving voltage (5~15V), flexible (suitable for plastic substrates) and simple manufacturing process, etc. , It is also an advantage beyond the popular LCD. However, the OLED panel must be driven by a stable voltage when it is in operation, so a grounding circuit is usually designed in the structure of the OLED panel to discharge the charge when the panel is turned off, but because the power to drive the OLED panel is very considerable , so it is a waste to export the residual power, and in the prior art US Patent No. 6501226 "Driving system and method for electroluminescence display" and No. 6594606 "Matrix element voltage sensing for precharge", it is mentioned that the use of array arrangement The anode line and the cathode line are connected to the power supply, so that the voltage can be recycled to reduce the switch voltage, but the voltage cycle effect in this article is only limited to the discussion of "voltage cycle", and there is no mention of how to store or apply voltage to components other than the power switch . Therefore, how to balance power saving, power recycling and protection circuit design is a problem that the industry needs to solve.

In view of this, the present invention aims at the above-mentioned problems, and proposes a charge recovery cycle circuit of a display device to effectively solve the above-mentioned problems.

Contents of the invention

The main purpose of the present invention is to provide such a charge recovery cycle circuit for a display device, which is designed to store discharged charges through an external capacitive element, and provided for use in the display device, so that the OLED display device can achieve the purpose of power saving.

Another object of the present invention is to provide such a charge recovery cycle circuit for a display device, which can provide power for operating elements in the display device, thereby increasing the usage efficiency of the power supply of the display device itself.

In order to achieve the above-mentioned purpose, according to the present invention, it is used to connect between the display panel of the display module and the source drive circuit. The display module has a source drive circuit and a gate drive circuit. When the source drive circuit is closed, the circuit recycling circuit will transfer charge to the external capacitance of the system, and the present invention includes a charge transfer circuit, which can guide the stored charge of the parasitic capacitance of the display panel to an external capacitance element of the system for storage, and between the charge transfer circuit and the source drive circuit A detection switch element is provided, and the detection switch element can detect the voltage level between the display panel and the source drive circuit, and determine the state of the path between the charge transfer circuit and the source drive circuit according to the light-emitting threshold voltage of the display panel with different color layers.

In the following, a detailed description will be made with specific embodiments in conjunction with the attached drawings, and it will be easier to understand the purpose, technical content, features and effects of the present invention.

Description of drawings

Fig. 1 is a schematic circuit diagram of the present invention.

FIG. 2 is a schematic circuit diagram of a charge transfer circuit composed of transistors according to the present invention.

FIG. 3 is a schematic circuit diagram of the present invention applied to a multi-color layer display panel.

FIG. 4 is a schematic circuit diagram of another multi-color layer display panel of the present invention.

Detailed ways

The present invention is a circuit recycling circuit for a display device. As shown in FIG. 1, the charge recycling circuit is connected between a display panel 12 and a source drive circuit 14 of a display module 10, and the display panel is an electroluminescence display. panel, such as organic light emitting diode (OLED) type or polymer organic light emitting diode (POLED) display panel, and this display module 10 has a source drive circuit 14, a gate drive circuit 16 and display panel 12, this display module 10 is in When the power is turned off, the parasitic capacitance of the display panel 12 will discharge the charge to the ground line of the display module 10, and the present invention includes a charge transfer circuit 18, which can guide the charge of the parasitic capacitance in the display panel 12 to a system The external capacitive element 20 is stored, and the charge stored in the external capacitive element 20 can be used by the operating elements in the display device, so that the external power supply 22 that supplies power to the display device can save power more effectively. In addition, a ground wire is also provided in the charge transfer circuit 18 to prevent the external capacitive element 20 from being discharged when the charge cannot be stored. Please also refer to FIG. A plurality of pre-drivers 24 are provided in the transfer circuit 18 to control the switch of each transistor to determine the direction of leading charges.

The charge recovery cycle circuit includes a detection switch element 26, the detection switch element 26 is arranged between the charge transfer circuit 18 and the source drive circuit 14, and the detection switch element 26 is provided with a voltage value, and the voltage value is for the display panel 12 to emit light. The critical value of the operation, the detection switch element 26 forms a pass state according to whether the voltage between the display panel 12 and the source driver circuit 14 is greater than this voltage value; that is, the detection switch element 26 determines the charge transfer circuit 18 according to the voltage of the display panel 12 The state of the channel with the source drive circuit 14. And when the detection switch element 26 forms a path, it will notify the charge transfer circuit 18, for example at least one notifies the pre-driver 24, so the pre-driver 24 controls the charge transfer circuit 18 to guide the direction of the charge, so that the charge recovery of the display device is completed loop circuit.

The above-mentioned embodiment is a monochromatic display module 10 type (as shown in Figures 1 and 2), and the color display module 10 will at least have two primary colors of red, green and blue, and there will be at least three display modules 28 relatively. 30 and 32 control the action of each primary color, as shown in Figure 3 and Figure 4, display module 10 has red light display module 28, green light display module 30 and blue light display module 32 three primary color layers among the figure, each color layer is composed of Corresponding red, green and blue source drive circuits 14 and gate drive circuits 16 control their actions, and in this color display module 10 type, the display modules 28, 30 and 32 that can select the three primary color layers share a detection switch element 26 And the charge transfer circuit 18, and the common detection switch element 26 can guide the parasitic capacitance charge of the display panel of each color layer in turn.

In addition, the driving module 16 of each color layer can also be connected to a detection switch element 26 and a charge transfer circuit 18 respectively, and lead to at least one external capacitor element 20 for storage.

When the present invention is in use, the charge is guided to the external capacitive element 20 of the system for storage, and the stored charge can be used by other operating elements in the display device, so that the burden on the external power supply 22 originally installed in the display device is reduced, thereby improving the performance of the display device. The usage efficiency of the external power supply 22. In addition, the present invention stores and utilizes the charges that were originally to be discharged, so as to achieve the advantage of power saving.

The above is to illustrate the characteristics of the present invention by means of the embodiments, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, rather than to limit the patent scope of the present invention, so all others do not depart from the present invention Equivalent modifications or modifications accomplished by the disclosed spirit should still be included in the scope of the patent application described below.

Claims (11)

1. the electric charge of a display device reclaims cycling circuit, it connects the display panel and the source driving circuit of a display module, this display panel has at least one driver module, this driver module can be discharged when closing on electric charge to the system external capacitive, and the electric charge of this display device reclaims cycling circuit and comprises:

One charge transfer circuit, its electric charge with this driver module are directed to this external capacitive element and store; And

One detector switch element, it is located between this charge transfer circuit and the source driving circuit, and this detector switch element is controlled channel status between this charge transfer circuit and the source driving circuit according to the magnitude of voltage between this driving panel and source driving circuit.

2. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, wherein, when this detector switch element forms path, can notify at least one pre-driver, and this pre-driver is controlled this charge transfer circuit guiding electric charge trend.

3. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, wherein, this display panel color is during at least two primary colors, this driver module is at least two and control each this primary colors start respectively, and each this driver module can independent or shared one this detector switch element and this charge transfer circuit.

4. the electric charge of display device as claimed in claim 3 reclaims cycling circuit, and wherein, this detector switch element can be guided the electric charge of each this driver module in turn.

5. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, wherein, this display panel color is during at least two primary colors, this driver module is at least two and control each this primary colors start respectively, and each this driver module can connect this detector switch element and this charge transfer circuit respectively, and directs at least one external capacitive element storage.

6. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, and wherein, this charge transfer circuit is by a plurality of transistor makers-ups of institute.

7. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, wherein, the electric charge that this external capacitive element is stored, the actuation element that can supply with in the display device uses.

8. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, and wherein, this detector switch element whether greater than its magnitude of voltage, whether to form channel status with decision according to the magnitude of voltage that drives panel and source driving circuit.

9. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, and wherein, this magnitude of voltage is one of luminous running of this a driver module and switch critical value.

10. the electric charge of display device as claimed in claim 1 reclaims cycling circuit, and wherein, this display panel is electroluminescent display panel person.

11. the electric charge of the display device of going back as claim 1 reclaims cycling circuit, wherein, this electroluminescent display panel includes OLED (OLED) pattern or macromolecule Organic Light Emitting Diode (POLED) display panel.

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