TWI622842B - Display device with passive component on display panel - Google Patents

Abstract

A display device includes a display panel in which a passive element is formed in the display panel; and a driving module coupled to the passive element for driving the display panel with the passive element.

Description

Display device implementing passive components on display panel

The present invention relates to a display device, and particularly to a display device in which a passive element is implemented on a display panel.

Electronic devices usually contain different components, and each component may require different operating voltages. Therefore, in an electronic device, it is necessary to adjust the voltage level (boost or step down) through a DC-to-DC voltage conversion circuit and stabilize it at a set voltage value. According to different power requirements, many different types of DC-DC voltage converters can be extended, but they are all derived from buck / step down converters and boost / step up converters Converter). As the name implies, a buck converter can reduce the DC voltage at the input to a preset voltage level, while a boost converter can boost the DC voltage at the input. Regardless of the step-down converter or step-up converter, with the evolution of circuit technology, both have evolved many changes to apply to different architectures or meet different needs.

In general, when a DC-to-DC voltage converter generates a voltage, the output of the DC-to-DC voltage converter must be coupled to a plurality of large-capacity stabilizing capacitors and / or flying capacitors to stabilize the DC-to-DC voltage conversion Voltage generated by the device. Stabilizing capacitors and flying capacitors are usually implemented by passive components placed on external circuit boards to meet the large capacitance requirements of stabilizing capacitors and flying capacitors. However, the addition of stabilizing capacitors and / or flying capacitors to external circuits will increase the cost of electronic devices. If a stabilizing capacitor and / or a flying capacitor are designed in a DC-to-DC voltage converter, the capacitance value per unit area in the internal circuit is too small, so that the DC-to-DC voltage converter needs to use a large amount of circuit area to achieve And / or flying capacitors, thereby significantly increasing the manufacturing cost of the DC-to-DC voltage converter. If the capacitance of the stabilizing capacitor and / or the flying capacitor implemented in the DC-to-DC voltage converter is reduced, in addition to the need to redesign the DC-to-DC voltage converter, the performance of the DC-to-DC voltage converter will also follow The capacitance of the stabilizing capacitor decreases. From the above, we know that there is a need to improve the conventional technology.

In order to solve the above problems, the present invention provides a display device in which a passive element is implemented on a display panel.

The present invention discloses a display device including a display panel in which a passive element is formed in the display panel; and a driving module coupled to the passive element for driving the display panel with the passive element.

By implementing the passive element on the display panel, the manufacturing cost of the display device can be effectively reduced. In addition, the impedance between the driving module and the passive components is also reduced, thereby reducing the power consumption of the driving module.

Certain terms are used in the description and the scope of subsequent patent applications to refer to specific elements. It should be understood by those with ordinary knowledge in the art that hardware manufacturers may use different names to refer to the same component. The scope of this specification and subsequent patent applications does not take the difference in names as a way to distinguish components, but rather uses the difference in functions of components as a criterion for distinguishing components. "Inclusion" mentioned throughout the specification and subsequent claims is an open-ended term and should be interpreted as "including but not limited to." In addition, the term "coupled" includes any direct and indirect means of electrical connection. Therefore, if a first device is described as being coupled to a second device, it means that the first device can be electrically connected directly to the second device or indirectly electrically connected to the second device through other devices or connection means.

Please refer to FIG. 1A, which is a schematic diagram of a display device 10 according to an embodiment of the present invention. The display device 10 may be an electronic product having a display panel such as a thin film transistor (TFT) liquid crystal display, a smart phone, or the like. For convenience of explanation, FIG. 1A only shows relevant components of the display module in the display device 10, and other components (such as a housing) that are not directly related to the concept of the present invention are omitted. The display device 10 includes a display panel 100 and a driving module 102. As shown in FIG. 1A, the display panel 100 includes an Inner Lead Bonding (ILB) region 104 and an Outer Lead Bonding (OLB) region 106. The inner pin area 104 includes various display elements (such as pixels, data lines and scan lines coupled to the pixels) for displaying images. FIG. 1A illustrates a plurality of pixels PIX as a representative. The outer pin area 106 includes a bonding pad that is connected to the driving module 102 and other external circuits (such as a flexible circuit board, not shown in FIG. 1A), and is used to provide the driving module 102 and the internal lead. The foot area 104 shows a connection path between the components. Through a bonding process, the driving module 102 is disposed in the outer pin region 106 and is coupled to the display element located in the inner pin region 104. The driving module 102 is used to generate a driving signal for driving the display elements in the inner pin area 104. For example, the driving module 102 may be a driving chip including a gate driver and a source driver (not shown in FIG. 1A), wherein the gate driver and the source driver are respectively used to generate a driver coupled to a pixel. Drive signals for scan lines and data lines. It is worth noting that the outer pin region 106 further includes a passive component 108, which is coupled to the driving module 102. The driving module 102 uses a passive element 108 to generate a driving signal for driving the display element in the inner pin area 104. That is, external passive components (such as capacitors) required for the driving module 102 to operate can be provided by the display panel 100, thereby reducing the manufacturing cost of the display device 10. In addition, since the passive element 108 can be implemented in the process structure of the display panel 100, the display device 10 can implement the passive element 108 without additional cost. In other words, by forming passive components required for the driving module 102 to operate on the display panel 100, the manufacturing cost of the display device 10 can be effectively reduced.

It should be noted that, after the passive component 108 is connected to the connection pad on the surface of the lower glass substrate BPS, it can be connected to the driving module 102 through other circuit components. For example, after the passive component 108 is connected to the connection pad on the surface of the lower glass substrate BPS, it can be connected to the driving module 102 through a flexible circuit board or a printed circuit board.

In detail, please refer to FIG. 1B, which is a side view of the display device 10 shown in FIG. 1A. As shown in FIG. 1B, the display panel 100 includes an upper polarizer TPF, an upper glass substrate UPS (such as a color filter substrate), a liquid crystal layer LC, a lower glass substrate BPS, a lower polarizer BPF, and a backlight module BLU. . As can be seen from FIG. 1B, the main display elements of the display panel 100 are all implemented in the inner pin area 104. Through the lamination process, the driving module 102 is disposed on the outer lead region 106 on the lower glass substrate BPS that is not covered by the upper polarizer TPF, the upper glass substrate UPS, the liquid crystal layer LC, and the lower polarizer BPF. Further, the passive element 108 is realized by a thin film layer deposited on the lower glass substrate BPS. The capacitive elements in the passive element 108 can be connected to the connection pads on the surface of the lower glass substrate BPS through wires, respectively. Through the pressing process, the driving module 102 disposed on the outer lead region 106 of the lower glass substrate BPS can be coupled to the passive component 108 through a wire and a connection pad.

In one embodiment, the passive element 108 is a capacitor unit, and the driving module 102 is a voltage stabilizing capacitor or a flying capacitor using the passive element 108 as a power circuit (such as a DC-to-DC voltage converter). In this embodiment, the driving module 102 performs charging and discharging operations on the passive component 108 during the operation process, so as to provide the power signal required by the driving module 102 to generate the driving signal by using the passive component 108. In this way, the driving module 102 does not need to spend a lot of area to realize the voltage stabilizing capacitor or flying capacitor required by the power circuit, thereby reducing the manufacturing cost of the driving module 102.

Compared with the conventional display device, the passive components required for the power supply circuit in the driving module 102 need to be additionally implemented on a circuit board (such as a flexible circuit board) coupled to the outer pin region 106. The embodiment of the present invention utilizes the display panel 100 The lower glass substrate BPS is used to implement the passive components required for the power circuit in the driving module 102. In this case, the display device 10 can provide passive components for the driving module 102 without additional cost. In addition, when the passive components coupled to the driving module 102 are implemented on a flexible circuit board coupled to the outer pin area 106, at least two pressing processes need to be performed to connect the driving module 102 to the circuit board connection. The pad and the connection pad of the flexible circuit board are connected to the passive components provided on the flexible circuit board. In contrast, in the above embodiment, the passive component 108 is formed in the outer pin area 106 close to the driving module 102, and the driving module 102 and the passive component 108 can be coupled with only one wire bonding process. Under this condition, the impedance between the driving module 102 and the passive element 108 can be reduced, thereby reducing the power consumption of the driving module 102 when the passive element 108 is used for charge and discharge operations.

Please refer to FIG. 2, which is a schematic diagram of an implementation manner of the lower glass substrate BPS in FIG. 1B. In this embodiment, the lower glass substrate BPS is implemented using a typical amorphous silicon thin film transistor process. As shown in FIG. 2, the lower glass substrate BPS includes a substrate SUB, a metal layer GL, a dielectric layer GI, an active layer AS, a metal layer SL, and a dielectric layer BP1, which are stacked from bottom to top. A conductive layer ITO1, a dielectric layer BP2, and a conductive layer ITO2. In the lower glass substrate BPS shown in FIG. 2, the metal layer GL is used to implement pixel scanning elements such as data lines, the metal layer SL is used to implement data lines, and the active layer AS is used to implement transistor elements in the display panel 100. The conductive layers ITO1 and ITO2 may be transparent and conductive indium tin oxide (Indium Tin Oxide), which are respectively used to form a pixel electrode and a common electrode. The materials of the dielectric layers GI, BP1, and BP2 are dielectric materials, and are used to separate the conductive metal layers GL and SL and the conductive layers ITO1 and ITO2. Because the passive element 108 can be implemented in the process structure of the lower glass substrate BPS. Therefore, the display device 10 can realize the use of the passive component 108 for the driving module 102 without extra cost.

Please refer to FIG. 3, which is a schematic diagram of a passive element 108 implemented on the lower glass substrate BPS in the embodiment of the present invention. In this embodiment, the passive element 108 includes a plurality of capacitors C108_1 to C108_4. As shown in FIG. 3, the passive element 108 uses the parallel-plate capacitor structure composed of the metal layer GL, the dielectric layer GI, and the metal layer SL in the lower glass substrate BPS to realize the capacitors C108_1 to C108_4. As shown in FIG. 3, the metal layer GL is one end of the capacitors C108_1 to C108_4, and is coupled to a reference potential (that is, the ground potential GND). The metal layers SL form the other ends of the capacitors C108_1 to C108_4, respectively. Through the architecture shown in FIG. 3, the lower glass substrate BPS can form a capacitor unit in the non-display area (such as the outer pin area 106) for the driving module 102 to use. Taking the material characteristics and device parameters of a typical amorphous silicon thin film transistor process as an example, a passive device implemented using the metal layer GL, the dielectric layer GI, and the metal layer SL in the lower glass substrate BPS only needs to have a side length of 1.3 mm. The square area can achieve 500 picofarad (PF).

According to different applications and design concepts, the passive component 108 can be implemented in different architectures. Please refer to FIG. 4, which is a schematic diagram of a passive element 108 implemented on the lower glass substrate BPS in the embodiment of the present invention. In this embodiment, the passive element 108 includes capacitors C108_1 to C108_4 implemented by a parallel plate capacitor structure composed of a metal layer GL, a dielectric layer GI, and a metal layer SL, and a metal layer SL, a dielectric layer BP3, and a conductor layer. Capacitors C108_5 to C108_8 implemented by a parallel plate capacitor architecture composed of ITO1. The metal layer SL is one end of the capacitors C108_1 to C108_8, and is coupled to the ground potential GND. The other ends of the capacitors C108_1 to C108_4 are respectively formed by the metal layer GL, and the other ends of the capacitors C108_5 to C108_8 are respectively formed of the conductive layer ITO1. Through the architecture shown in Figure 4, the capacitance value per unit area provided on the lower glass substrate BPS can be improved.

It can be seen from FIGS. 3 and 4 that the passive element 108 can use at least two conductive layers (such as metal layers GL and SL and at least two of the conductive layers ITO1 and ITO2) in the lower glass substrate to realize the capacitor unit. In one embodiment, the passive element 108 is implemented by a parallel electrical plate structure formed by the conductive layer ITO1, the dielectric layer BP2, and the conductive layer ITO2.

It should be noted that the passive element 108 is not limited to be implemented in the outer pin region 106. According to different applications and design concepts, the passive component 108 can also be implemented in areas other than the outer pin area 106. For example, the passive element 108 may also be implemented in a region of the inner pin region 104 that is not used to implement pixels. That is, the passive element 108 may be implemented in a non-display area in the display panel 100.

Please refer to FIG. 5, which is a schematic diagram of the driving module 102 and the passive element 108 according to the embodiment of the present invention. In this embodiment, the driving module 102 includes a power supply unit 500 and capacitors CINT1 and CINT2, and the passive element 108 includes capacitors CEXT1 to CEXT3. In detail, when an external circuit (not shown in FIG. 5) outputs an external power source VEXT to the driving module 102, the external circuit may be implemented through a flexible circuit board or a printed circuit board (not shown in FIG. 5) and implemented. The capacitor CEXT1 on the lower glass substrate BPS is electrically connected to reduce the voltage disturbance of the external power source VEXT by using the capacitor CEXT1. The power supply unit 500 may be a buck-boost circuit such as a DC-to-DC converter. The power supply unit 500 is used to generate a power supply VDD to the driving module 102 by using a flying capacitor CF composed of capacitors CINT1 and CEXT2 in parallel. The rest of the circuit. Capacitors CINT2 and CEXT3 are connected in parallel to form a voltage stabilizing capacitor CS coupled to the power supply VDD to reduce the voltage disturbance on the power supply VDD. Since the capacitors CEXT1 and CEXT2 can share the capacitance values of the flying capacitor CF and the stabilizing capacitor CS respectively, the areas of the capacitors CINT1 and CINT2 in the driving module 102 can be reduced, thereby reducing the manufacturing cost of the driving module 102. According to different applications and design concepts, the flying capacitor CF and the stabilizing capacitor CS required for the operation of the power supply unit 500 can be completely realized by the capacitors CEXT2 and CEXT3 of the passive component 108, and the capacitors CINT1 and CINT2 in the driving module 102 can be omitted. In order to further reduce the manufacturing cost of the driving module 102.

In the above embodiment, the display device can implement the passive components required for the operation of the driving module on the display panel without additional cost. According to this, the driving module does not need to spend a lot of circuit area to implement passive components, thereby effectively reducing the manufacturing cost of the driving module. Further, by implementing the passive element on the display panel, the impedance between the driving module and the passive element can be reduced. As a result, the power consumption of the drive module will be reduced accordingly. The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in accordance with the scope of patent application of the present invention shall fall within the scope of the present invention.

10‧‧‧ display device

100‧‧‧ display panel

102‧‧‧Driver Module

104‧‧‧Inner pin area

106‧‧‧ Outer pin area

108‧‧‧Passive components

500‧‧‧ Power Supply Unit

AS‧‧‧Active layer

BLU‧‧‧Backlight Module

BP1, BP2, GI‧‧‧ dielectric layers

BPF‧‧‧ bottom polarizer

BPS‧‧‧ Lower glass substrate

C108_1 ~ C108_8, CINT1, CINT2 CEXT1 ~ CEXT3‧‧‧Capacitor

GL, SL‧‧‧metal layer

ITO1, ITO2‧‧‧conductor layer

LC‧‧‧LCD layer

TPF‧‧‧ Upper Polarizer

UPS‧‧‧ on glass substrate

VDD‧‧‧ Power

VEXT‧‧‧External Power

FIG. 1A is a schematic diagram of a display device according to an embodiment of the present invention. Fig. 1B is a side view of the display device shown in Fig. 1A. FIG. 2 is a schematic diagram of an implementation manner of a lower glass substrate in the display device shown in FIG. 1B. FIG. 3 is a schematic diagram of a passive component according to an embodiment of the present invention. FIG. 4 is a schematic diagram of a passive component according to an embodiment of the present invention. FIG. 5 is a schematic diagram of a passive component and a driving module according to an embodiment of the present invention.

Claims (9)

A display device includes: a display panel in which a passive element is formed in an inner pin area of the display panel; and a driving module coupled to the passive element for driving the passive element using the passive element. A display panel; wherein the inner lead region is covered by an upper glass substrate, and the passive element is formed in an area of the inner lead region that is not used to implement pixels. The display device according to claim 1, wherein the passive element is formed on a lower glass substrate. The display device according to claim 1, wherein the inner lead region includes at least one metal conductor layer, at least one transparent conductor layer, and at least one dielectric layer. The display device according to claim 1, wherein the passive element includes a capacitor unit. The display device according to claim 4, wherein the driving module uses the capacitor unit to provide a power signal required for the driving module to operate. The display device according to claim 4, wherein the driving module uses the capacitor unit to stabilize the voltage value of the voltage source. The display device according to claim 4, wherein the capacitor unit includes: a first conductive layer coupled to a reference potential; a first dielectric layer formed on the first conductive layer; and a first Two conductor layers are formed on the first conductive layer. The display device according to claim 7, wherein the capacitor unit further comprises: a second dielectric layer formed under the first conductive layer; and a third conductor layer formed in the second dielectric layer under. The display device according to claim 1, wherein the passive component is coupled to the driving module through one of a flexible printed board and a printed circuit board.