A display device and equipment

Abstract

The present invention relates to a display device, comprising a substrate, a circuit layer, a plurality of light-emitting units and a control chip; the circuit layer is laid on the surface of the substrate and comprises an independent first circuit layer and a second circuit layer; the plurality of light-emitting units are die-bonded on the substrate, each light-emitting unit comprises a plurality of light-emitting chips of different light colors, and the first electrodes of the light-emitting chips of different light colors inside each light-emitting unit are connected in parallel to a corresponding electrode of the control chip through the first circuit layer; the respective second electrodes are connected to the corresponding electrodes of the control chip through the second circuit layer. By using the display device of the present invention, the number of electrodes of the control chip can be reduced, the number of bonding wires can be saved, thereby reducing the size of the control chip and the distance between the light-emitting chips, and achieving the small-size effect of the whole device.

Description

Technical Field

[0001] The present invention relates to the field of integrated circuits, and in particular to a display device. Background Art

[0002] Today's electronic devices are usually equipped with display functions to facilitate real-time control and daily use. Display devices provide display functions for electronic devices, so the performance of display devices directly affects people's experience of using electronic devices. LED is the most commonly used light-emitting device in display devices. By using LED lights of different colors as light-emitting chips, the demand for any light-emitting color can be met. For changing colors, an IC driver chip is required as a control chip to accurately control the color output of the light-emitting chip.

[0003] See also Figure 1 The four-in-one lamp-driven display device is one of the most outstanding display devices in the existing performance. It includes a substrate 10, a circuit layer 20, four light-emitting units 30, a conductive line 40 and a control chip 50. The circuit layer 20 is paved on the surface of the substrate 10 and includes a series of circuits. The four light-emitting units 30 are all solid-chip on the substrate 10 and connected in series through the circuit layer 20. Figure 1 The middle dotted line represents the conductive wire of the conductive wire 40. One end of each conductive wire is bonded to an electrode in the light-emitting unit 30, and the other end is bonded to the electrode corresponding to the control chip 50 installed on the substrate 10 with the front side facing up. Some electrodes of the control chip 50 are also bonded to the conductive wire to connect to an external voltage source (not shown).

[0004] Specifically, the light-emitting unit 30 includes a red light-emitting chip 31, a green light-emitting chip 32 and a blue light-emitting chip 33. One electrode of the red light-emitting chip 31, the green light-emitting chip 32 and the blue light-emitting chip 33 is individually bonded to an electrode of the control chip 50 through a conductive wire, and the other electrode is bonded to the substrate 10, and then connected in series through the circuit layer 20 and connected to the corresponding electrode of the control chip 50; wherein the conductive wires connected to the control chip 50 and the external voltage source form a total of 26 bonding wires.

[0005] However, any abnormal welding of any bonding wire in the existing display device will cause the display function of the entire device to be incomplete or even fail, and the bonding cost is high and the stability is poor. In addition, due to the large number of bonding wires and corresponding electrodes, the control chip 50 must be larger than a certain size to accommodate enough electrodes, and the point spacing between different light-emitting units 30 is equal to the side length of the control chip 50 plus the width of the corresponding tin wires on both sides, and the minimum can only reach P0.9 (900μm), resulting in the size of the entire display device cannot be reduced. Summary of the invention

[0006] Based on this, the object of the present invention is to provide a display device, which can reduce the number of electrodes and the number of wire bonds of the conductive wires, reduce the chip pitch so as to reduce the overall size, lower the production cost while maintaining high stability.

[0007] A display device includes a substrate, a circuit layer, a plurality of light-emitting units, and a control chip;

[0008] The circuit layer is disposed on the surface of the substrate and includes an independent first circuit layer and a second circuit layer;

[0009] The plurality of light-emitting units are die-bonded on the substrate. Each light-emitting unit includes a plurality of light-emitting chips of different light colors. The first electrodes of the light-emitting chips of different light colors inside each light-emitting unit are connected in parallel to one corresponding electrode of the control chip through the first circuit layer; and their second electrodes are connected to the corresponding electrodes of the control chip through the second circuit layer.

[0010] Further, the second electrodes of the light-emitting chips of the same light color between different light-emitting units are connected in parallel to one corresponding electrode of the control chip through the second circuit layer.

[0011] Further, the light-emitting units are mounted on one side surface of the substrate; and are mounted on the same side surface of the substrate as the control chip.

[0012] Further, the light-emitting units and the control chip are mounted on different surfaces of the substrate.

[0013] Further, a plurality of pads are fixed on the substrate, and the pads are electrically connected to the electrodes of the light-emitting units and the control chip.

[0014] Further, the light-emitting units and the control chip are inversely fixed on the substrate, and their electrodes are fixed on a partial area brushed with solder on the pads by hot melting of solder paste.

[0015] Further, the circuit layer further includes a third circuit layer independent of the first circuit layer and the second circuit layer, and the control chip is connected to an external signal source and a voltage source through the third circuit layer.

[0016] Further, two filter capacitors are further included. The two filter capacitors are respectively connected in series between the two signal input electrodes of the control chip and the external signal source for filtering out clutter and interference signals in the data signal.

[0017] Further, a voltage stabilizing capacitor is further included. The voltage stabilizing capacitor is connected in parallel between the ground electrode and the voltage source electrode of the control chip and the external voltage source for maintaining a stable voltage input.

[0018] Further, adjacent display devices among the multiple display devices are connected in parallel through a third circuit layer, and the connection directions of the control units in different display devices are perpendicular to the connection directions of the light-emitting units in each display device.

[0019] Further, adjacent display devices among the multiple display devices are connected in parallel through a third circuit layer, and the connection directions of the control units in different display devices are parallel to the connection directions of the light-emitting units in each display device.

[0020] The present invention also provides a display device, including a driver and multiple display devices as described above. The driver is connected to the multiple display devices to control the display changes of the display devices.

[0021] Further, along a direction perpendicular to the connection direction between different light-emitting units, adjacent display devices are electrically connected in sequence. The driver is installed at the top or bottom of the display device, and the display device is designed longitudinally.

[0022] Further, along a direction parallel to the connection direction between different light-emitting units, adjacent display devices are electrically connected in sequence. The driver is installed on the left or right side of the display device, and the display device is designed horizontally.

[0023] For better understanding and implementation, the present invention will be described in detail below with reference to the accompanying drawings. Description of the Drawings

[0024] Figure 1 It is a schematic structural diagram of an existing display device.

[0025] Figure 2 It is a schematic structural diagram of the display device of the present invention.

[0026] Figure 3 For Figure 2 It is a schematic diagram of the spatial structure of the light-emitting units on the substrate in the display device.

[0027] Figure 4 It is a schematic diagram of the connection positions and soldering tin areas of the first electrode and the second electrode of the light-emitting unit on the pads.

[0028] Figure 5 For one Figure 3 It is a schematic diagram of the structure of anodic parallel connection between light-emitting chips of different light colors in the light-emitting unit Figure 3 and Figure 4 .

[0029] Figure 6 For multiple Figure 3 It is a schematic diagram of the structure of cathodic parallel connection between light-emitting chips of the same light color in the light-emitting unit.

[0030] Figure 7 is Figure 2 a schematic diagram of the spatial structure of the control chip on the substrate in the display device.

[0031] Figure 8 is Figure 2 a schematic diagram of the structure in which the light-emitting unit and the control chip in the display device are arranged on the same layer on the substrate surface.

[0032] Figure 9 is Figure 2 a schematic diagram of the structure in which the light-emitting unit and the control chip in the display device are arranged on different layers on the substrate surface.

[0033] Figure 10 is multiple Figure 2 a connection method of the display device.

[0034] Figure 11 is a schematic diagram of the longitudinal installation structure of the display device of the present invention.

[0035] Figure 12 is a schematic diagram of the horizontal installation structure of the display device of the present invention. Detailed implementation manners

[0036] The inventor carefully analyzed the existing display devices and found that the cathodes and anodes of the red light-emitting chip, green light-emitting chip, and blue light-emitting chip are each separately wire-bonded to the control chip through conductive wires, resulting in a large number of conductive wires to be wire-bonded. Therefore, the inventor tried to parallel the first electrodes of the light-emitting chips of the same light color in the same light-emitting unit and parallel the second electrodes of the light-emitting chips of the same light color in different light-emitting units, so as to control the same number of light-emitting chips with fewer electrodes.

[0037] Please refer to Figure 2 , based on the above inventive concept, the inventor provides a display device, including a substrate 10, a circuit layer 20, 4 light-emitting units 30, a control chip 50, two filter capacitors 60, and a voltage stabilizing capacitor 70. The circuit layer 20 is paved on the surface of the substrate 10 and includes independent first circuit layer 21, second circuit layer 22, and third circuit layer 23; 4 light-emitting units 30 are all die-bonded on the substrate 10, and the first electrodes of the light-emitting chips of different light colors in each light-emitting unit 30 are connected in parallel to an electrode of the control chip 50 through the first circuit layer 21, and the second electrodes of the light-emitting chips of the same light color in different light-emitting units 30 are connected in parallel to an electrode of the control chip 50 through the second circuit layer 22. The control chip 50 is installed on the substrate 10, and part of the electrodes are connected to an external signal source through the third circuit layer 23 after passing through the filter capacitor 60 and are connected to an external voltage source after passing through the voltage stabilizing capacitor 70.

[0038] The substrate 10 is a common substrate, on the surface of which there is a circuit layer 20. The circuit layer 20 reserves positions for the installation of other components and has a positioning function at the same time. A plurality of pads 11 are fixed on the substrate 10. The pads 11 are made of conductive and heat-conductive materials such as metal and are used for electrical connection with the electrodes of electronic devices. A plurality of conductive holes are also provided on the substrate 10. Conductive metal can be filled in the conductive holes to form a conductive column that conducts up and down, realizing the electrical connection of points on two surfaces of the substrate 10. Since the circuit layer 20 is a planar laying with negligible thickness, when there is an overlap between the first circuit layer 21, the second circuit layer 22 and the third circuit layer 23, short circuit will occur if they are arranged on the same surface of the substrate 10. However, the staggered arrangement of the circuit layers 20 on two surfaces can be realized through the connection of conductive columns, without affecting their respective conductive results.

[0039] The circuit layer 20 is made of conductive materials such as copper foil and serves as the basic conductive circuit of the substrate 10. Its thickness can be ignored. Since the width of the conductive circuit determines its own resistance, its width is determined by the voltage and current magnitudes required in the actual working environment. Specifically, the circuit layer 20 can be formed by depositing a copper layer at the corresponding position of the substrate 10 through electrolysis.

[0040] The light-emitting unit 30 includes a red light-emitting chip 31, a green light-emitting chip 32 and a blue light-emitting chip 33 arranged at intervals. The red light-emitting chip 31, the green light-emitting chip 32 and the blue light-emitting chip 33 only have different light-emitting wavelengths, and other structural settings are not limited. Please refer to Figure 3, taking the blue light-emitting chip 33 as an example, its structure will be described in detail. The blue light-emitting chip 33 includes a light-emitting core 331, a first electrode 332 and a second electrode 333 disposed at the bottom of the light-emitting core 331. The light-emitting core 331 is fixed on the pad 11 by hot melting of solder paste through the first electrode 332 and the second electrode 333. The light-emitting core 331 is electrically connected to the circuit layer 20 on the surface of the substrate 10 through the pad 11. The heat generated by the light-emitting core 331 during operation can be transferred to the outside through the pad 11 and the substrate 10 in sequence, ensuring the normal working temperature inside the light-emitting core 331. Those skilled in the art can understand that the number of the light-emitting units 30 is not limited to 4. Using 4 light-emitting units 30 is only an embodiment of the present invention. In fact, the light-emitting units 30 can be n, and only need to control the number of electrodes of the chip 50 corresponding to the connected light-emitting units 30 to be n + 3, where n ≥ 1; similarly, the number of light-emitting chips of different light colors in each light-emitting unit 30 is not limited to 3, and the colors are not limited to red, green and blue. Using 3 light-emitting chips of different light colors is only an embodiment of the present invention. In fact, the light-emitting chips of different light colors can be m, and only need to control the number of electrodes of the chip 50 corresponding to the connected light-emitting units 30 to be n + m, where m ≥ 1. Compared with the existing display device in which the number of electrodes of the control chip 50 corresponding to the connected light-emitting units 30 is 3n, the display device of the present invention reduces the number of electrodes required on the control chip 50, and the more the number of the light-emitting units 30, the more obvious the reduction in the required number of electrodes. Due to the reduction in the required number of electrodes, the size of the control chip 50 can be correspondingly reduced, and after the size is reduced, it can still accommodate a sufficient number of electrodes for normal operation. Please refer to Figure 4 , Figure 4 FIG. Figure 4 is a schematic diagram of the positions and solder-brushing areas of the first electrode 332 and the second electrode 333 of the blue light-emitting chip 33 on the pad 11. The solid-line rectangular area in the inner circle is the area where the first electrode 332 and the second electrode 333 are located, the solid-line rectangular area in the outer circle is the area where the pad 11 is located, and the dotted-line area is the solder-brushing area of the pad 11. Among them, on each pad, one edge of the solder-brushing area coincides with one edge of the electrode and is at a certain distance from the edge of the pad to prevent problems such as short circuit caused by the flow of solder paste during solder brushing. The position of the first electrode 332 on its corresponding pad 11 is the same as the position of the second electrode 333 on its corresponding pad 11, and they are symmetrically arranged in this embodiment. The pad 11 is soldered in the solder-brushing area using a stencil and connected to the circuit layer 20 to achieve the electrical connection between the light-emitting core 331 and the circuit layer 20.

[0041] Please refer to Figure 5 , Figure 5Shows the connection of the first electrode 332 among the red light-emitting chip 31, the green light-emitting chip 32, and the blue light-emitting chip 33 in a light-emitting unit 30. Specifically, the first electrode 332 is an anode. The anodes of the red light-emitting chip 31, the green light-emitting chip 32, and the blue light-emitting chip 33 in the light-emitting unit 30 are connected in parallel through the first circuit layer 21.

[0042] Please refer to Figure 6 , Figure 6 Shows the connection of the second electrode 333 among the red light-emitting chips 31 in different light-emitting units 30, the connection of the second electrode 333 among the green light-emitting chips 32, and the connection of the second electrode 333 among the blue light-emitting chips 33. Specifically, the second electrode 333 is a cathode. The cathodes of the different light-emitting units 30 are connected in parallel through the second circuit layer 22.

[0043] Please refer to Figure 7 , Figure 7 Is a schematic diagram of the spatial structure of the control chip 50 on the substrate 10. The structure of the control chip 50 is basically the same as that of the blue light-emitting chip 33, except that the control chip 50 has multiple electrodes instead of only two electrodes, namely the first electrode and the second electrode, and the size of the control chip 50 is larger than that of the light-emitting chip.

[0044] Specifically, the control chip 50 includes an IC driving core 51 and driving electrodes 52. The IC driving core 51 is connected to the light-emitting unit 30 through the driving electrodes 52. The control chip 50 is a flip-chip. The driving electrodes 52 are arranged between the IC driving core 51 and the substrate 10. Through the flip-chip arrangement, the IC driving core 51 can be directly connected to the circuit of the substrate 10 through the driving electrodes 52 without the need for bonding wires, thus omitting the use of wires and reducing production costs.

[0045] Particularly, the driving electrodes 52 include (n + 3) control electrodes, two signal input electrodes, one signal output electrode, one voltage source electrode, and one ground electrode. The (n + 3) control electrodes are respectively connected to the electrodes of n light-emitting units 30; the signal input electrodes include D1 and D2 electrodes, and the D1 and D2 electrodes are respectively connected to two filtering capacitors; the signal output electrode is the DO electrode; the voltage source electrode is the VCC electrode or the VDD electrode, which provides a voltage source for the control chip 50; the ground electrode is the GND electrode.

[0046] The two filtering capacitors 60 are respectively connected in series between the two signal input electrodes of the control chip 50 and an external signal source, and are used to filter out the clutter and interference signals in the data signal to ensure the accuracy of long-distance signal transmission.

[0047] The voltage stabilizing capacitor 70 is connected in parallel between the ground electrode and the voltage source electrode of the control chip 50 and the external voltage source, reducing voltage fluctuations, maintaining the stability of voltage input, and preventing damage to the control chip 50.

[0048] Please refer to Figure 8 , in one embodiment, the light emitting unit 30 and the control chip 50 are arranged on the same layer. Figure 7 A cross-section of the display device of the present invention is shown. From this cross-section, the blue light emitting chip 33 of the light emitting unit 30 can be seen. Since the red light emitting chip 31 and the green light emitting chip 32 of the light emitting unit 30 have the same electrical structure as the blue light emitting chip 33 except for the different light colors emitted by photoelectric conversion, therefore, at the angle of this cross-section, a blue light emitting chip 33 can also be used as an example to replace the description. At this time, the remaining light emitting chips do not need to be considered, reducing the repetition and redundancy of the description. The minimum distance between the first electrode 332 or the second electrode 333 of the blue light emitting chip 33 and the driving electrode 52 of the control chip 50 is the smallest line pitch in the line layer 20. In this setting, the light emitting unit 30 and the control chip 50 can be simultaneously fixed on the substrate 10 by hot melting of solder paste, and only one die bonding operation is required. The process is simple and the cost is low; however, limited by the line pitch of the line layer 20, the device size is large.

[0049] Please refer to Figure 9 , in another embodiment, the light emitting unit 30 and the control chip 50 are arranged on different two layers. Figure 9 Shows the same cross-section as Figure 8 . The light emitting unit 30 is arranged on one side of the substrate 10, and the control chip 50 is arranged on the other side of the substrate 10. The driving electrode 52 of the control chip 50 is directly connected to the electrode corresponding to the blue light emitting chip 33 on the other side of the substrate 10 through a conductive column. In this setting, the line pitch of the line layer 20 does not need to be considered, and the device size only depends on the size of the control chip 50 itself. Therefore, the device size can reach the level of P≤0.5(500μm); however, in this setting, the light emitting unit 30 needs to be die bonded first and then the control chip 50 needs to be die bonded, increasing the process difficulty. It can be understood that the interlayer setting of the control chip 50 and the light emitting unit 30 in the display device of the present invention can be selected according to actual needs to achieve the optimal implementation effect.

[0050] Particularly, please refer to Figure 10 , when multiple display devices are connected together, adjacent display devices can be connected in parallel through the third line layer 23. Specifically, the voltage source electrodes of multiple display devices are connected in parallel, the ground electrodes are connected in parallel, and the signal output electrode DO of the previous display device is connected to the signal input electrodes DI1 and DI2 of the next display device. It can be understood thatFigure 10 Only one setting case is shown, in which the connection direction of the control unit in different display devices is perpendicular to the connection direction of the light-emitting units in each display device. In fact, the connection direction of the control unit in different display devices and the connection direction of the light-emitting units in each display device can also be parallel or a three-dimensional vertical structure in different planes. The specific installation needs to be adjusted according to actual requirements, and the applicable range is wide.

[0051] In addition, the present invention also provides a display device, including a driver and a plurality of the above-described display devices. The plurality of display devices are electrically connected through conductive wires, and the driver is connected to the display device through the conductive wires.

[0052] Please refer to Figure 11 , in one embodiment, along a direction perpendicular to the connection direction between different light-emitting units 30, adjacent display devices are electrically connected in sequence. The driver is installed at the top or bottom of the display device, so that the entire display device forms a longitudinal design, which is applicable to the case where the height condition of the user's use environment is relatively high and the width condition is relatively low.

[0053] Please refer to Figure 12 , in another embodiment, along a direction parallel to the connection direction between different light-emitting units 30, adjacent display devices are electrically connected in sequence. The driver is installed on the left or right side of the display device, and the entire display device forms a horizontal design, which is applicable to the case where the width condition of the user's use environment is relatively high and the height condition is relatively low. It can be understood that the display device of the present invention does not limit the specific installation method, and the user can select according to actual needs. Its applicable range is wide and its practicability is strong.

[0054] The above-described embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and the present invention also intends to include these modifications and improvements.

Claims

1. A display device, characterized in that: It includes a substrate, a circuit layer, a plurality of light-emitting units and a control chip; The circuit layer is laid on the surface of the substrate, including a first circuit layer and a second circuit layer that are independent of each other; The multiple light-emitting units are die-bonded on the substrate, and each light-emitting unit includes multiple light-emitting chips of different light colors. The first electrodes of the light-emitting chips of different light colors in each light-emitting unit are respectively connected in parallel to an electrode corresponding to the control chip through the first circuit layer; the second electrodes of the light-emitting chips of different light colors in each light-emitting unit are respectively connected in parallel to an electrode corresponding to the control chip through the second circuit layer; the second electrodes of the light-emitting chips of the same light color between different light-emitting units are respectively connected in parallel to an electrode corresponding to the control chip through the second circuit layer.

2. The display device according to claim 1, characterized in that: The light emitting unit is mounted on one side surface of the substrate; and the control chip is mounted on the same side surface of the substrate.

3. The display device according to claim 1, characterized in that: The light emitting unit and the control chip are mounted on different surfaces of the substrate.

4. The display device according to claim 2 or 3, characterized in that: A plurality of pads are fixed on the substrate, and the pads are electrically connected to the electrodes of the light emitting unit and the control chip.

5. The display device according to claim 4, characterized in that: The light emitting unit and the control chip are fixed upside down on the substrate, and the electrodes thereof are fixed to the tinned part of the pad by hot melting of solder paste.

6. The display device according to claim 5, characterized in that: The circuit layer also includes a third circuit layer that is independent of the first circuit layer and the second circuit layer, and the control chip is connected to an external signal source and a voltage source through the third circuit layer.

7. The display device according to claim 6, characterized in that: It also includes two filter capacitors, which are respectively connected in series between the two signal input electrodes of the control chip and the external signal source to filter clutter and interference signals in the data signal.

8. The display device according to claim 6, characterized in that: It also includes a voltage-stabilizing capacitor, which is connected in parallel between the ground electrode and the voltage source electrode of the control chip and the external voltage source to maintain a stable voltage input.

9. The display device according to claim 7 or 8, characterized in that: Adjacent display devices among the plurality of display devices are connected in parallel via a third circuit layer, and a connection direction of control units in different display devices is perpendicular to a connection direction of light-emitting units in each display device.

10. The display device according to claim 7 or 8, characterized in that: Adjacent display devices among the plurality of display devices are connected in parallel via a third circuit layer, and a connection direction of control units in different display devices is parallel to a connection direction of light-emitting units in each display device.

11. A display device, characterized in that: The invention comprises a driver and a plurality of display devices according to any one of claims 1 to 10, wherein the driver is connected to the plurality of display devices to control display changes of the display devices.

12. The display device according to claim 11, characterized in that: Adjacent display devices are electrically connected in sequence along a direction perpendicular to a connection direction between different light-emitting units, the driver is mounted on the top or bottom of the display device, and the display device forms a vertical design.

13. The display device according to claim 11, characterized in that: Adjacent display devices are electrically connected in sequence along a direction parallel to a connection direction between different light-emitting units, the driver is installed on the left or right side of the display device, and the display device forms a horizontal design.

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