Display device and equipment

Abstract

The invention relates to a display device which comprises 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 a first circuit layer and a second circuit layer which are mutually independent; the plurality of light-emitting units are die-bonded on the substrate, each light-emitting unit comprises a plurality of light-emitting chips with different light colors, and respective first electrodes of the light-emitting chips with different light colors in each light-emitting unit are connected in parallel to an electrode corresponding to the control chip through the first circuit layer; and the respective second electrodes are connected with the corresponding electrodes of the control chip through the second circuit layer. By the adoption of the display device, the number of electrodes of the control chip can be reduced, the number of bonding conductive wires is reduced, the size of the control chip is reduced, the distance between the light-emitting chips is reduced, and the small-size effect of the whole device is achieved.

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, an object of the present invention is to provide a display device that can reduce the number of electrodes and the number of bonding of conductive wires, narrow the chip spacing to reduce the overall size, reduce production costs while maintaining high stability.

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

[0008] 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;

[0009] The multiple light-emitting units are solid-chip on the substrate, and each light-emitting unit includes multiple light-emitting chips of different light colors. The first electrode of each light-emitting chip of different light colors in each light-emitting unit is connected in parallel to an electrode corresponding to the control chip through the first circuit layer; and the second electrode of each light-emitting unit is connected to the electrode corresponding to the control chip through the second circuit layer.

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

[0011] Furthermore, 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.

[0012] Furthermore, the light emitting unit and the control chip are mounted on different surfaces of the substrate.

[0013] Furthermore, 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.

[0014] Furthermore, 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.

[0015] Furthermore, 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.

[0016] Furthermore, two filter capacitors are 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 to filter clutter and interference signals in the data signal.

[0017] Furthermore, 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.

[0018] Furthermore, 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.

[0019] Furthermore, 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.

[0020] The present invention further provides a display device, comprising a driver and a plurality of the above-mentioned display devices, wherein the driver is connected to the plurality of display devices to control display changes of the display devices.

[0021] Furthermore, 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.

[0022] Furthermore, 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.

[0023] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure 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 Schematic diagram of the spatial structure of the light-emitting unit on the substrate in the display device.

[0027] Figure 4 It is a schematic diagram of the connection position of the first electrode and the second electrode of the light-emitting unit on the pad and the tinning area.

[0028] Figure 5 For one Figure 3 Schematic diagram of the structure of the anodes of the light-emitting chips with different light colors in the light-emitting unit being connected in parallel Figure 3 and Figure 4 .

[0029] Figure 6 For multiple Figure 3 A schematic structural diagram of cathode parallel connection between light-emitting chips of the same light color in the light-emitting unit.

[0030] Figure 7 for Figure 2 Schematic diagram of the spatial structure of the control chip on the substrate in the display device.

[0031] Figure 8 for 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 surface of the substrate.

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

[0033] Fig.10 For multiple Figure 2 A method of interconnecting the display devices.

[0034] Fig.11 It is a schematic structural diagram of a display device of the present invention installed vertically.

[0035] Fig.12 It is a schematic structural diagram of a display device of the present invention installed horizontally. DETAILED DESCRIPTION

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

[0037] See also Figure 2 Based on the above invention concept, the inventor provides a display device, including a substrate 10, a circuit layer 20, four 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 a first circuit layer 21, a second circuit layer 22 and a third circuit layer 23 that are independent of each other; the four light-emitting units 30 are all die-bonded on the substrate 10, and the first electrodes of the light-emitting chips with 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 with the same light colors 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 mounted on the substrate 10, and some electrodes are connected to an external signal source through the third circuit layer 23 and the filter capacitor 60, and are connected to an external voltage source through the voltage-stabilizing capacitor 70.

[0038] The substrate 10 is a common substrate, and a circuit layer 20 is provided on its surface. The circuit layer 20 reserves a position for the installation of other components and has a positioning function. A plurality of pads 11 are fixed on the substrate 10. The pads 11 are conductive heat transfer materials such as metals, and are used to electrically connect with the electrodes of electronic devices. A plurality of conductive holes are also provided on the substrate 10. The conductive holes can be filled with conductive metal to form a conductive column that is connected up and down to achieve electrical connection between points on the two surfaces of the substrate 10. Since the circuit layer 20 is a plane with negligible thickness, when there is overlap between the first circuit layer 21, the second circuit layer 22 and the third circuit layer 23, if they are arranged on the same surface of the substrate 10, a short circuit will result. However, the circuit layers 20 on the two surfaces can be interlaced by connecting through conductive columns, which will not affect the respective conductive results.

[0039] The circuit layer 20 is made of conductive materials such as copper foil, and 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 required in the actual working environment. Specifically, the circuit layer 20 can be formed by depositing a copper layer at a 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 are different in light emission wavelengths, and other structural arrangements are not limited. Figure 3, taking the blue light emitting chip 33 as an example, its structure is described in detail. The blue light emitting chip 33 includes a light emitting core 331 and a first electrode 332 and a second electrode 333 arranged 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 turn, ensuring that the internal working temperature of the light emitting core 331 is normal. Those skilled in the art can understand that the number of light-emitting units 30 is not limited to 4. Using 4 light-emitting units 30 is only one embodiment of the present invention. In fact, the number of light-emitting units 30 can be n. It only needs to control the number of electrodes connected to the light-emitting units 30 of the control chip 50 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 one embodiment of the present invention. In fact, the number of light-emitting chips of different light colors can be m. It only needs to control the number of electrodes connected to the light-emitting units 30 of the control chip 50 to be n+m, where m≥1. Compared with the existing display device in which the number of electrodes connected to the light-emitting units 30 of the control chip 50 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 light-emitting units 30, the more obvious the reduction in the number of electrodes required. Since the number of required electrodes is reduced, the size of the control chip 50 can be reduced accordingly, 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 The schematic diagram of the position of the first electrode 332 and the second electrode 333 of the blue light emitting chip 33 on the pad 11 and the tinning area, the solid rectangular area of ​​the inner circle is the area where the first electrode 332 and the second electrode 333 are located, the solid rectangular area of ​​the outer circle is the area where the pad 11 is located, and the area of ​​the dotted line is the tinning area of ​​the pad 11, wherein the edge of one side of the tinning area on each pad coincides with the edge of one side of the electrode, and is a certain distance away from the edge of the pad to prevent the solder paste from flowing out during tinning and causing problems such as short circuits. 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 tinned in the tinning area using a steel mesh and connected to the circuit layer 20 to achieve electrical connection between the light emitting core 331 and the circuit layer 20.

[0041] See also Figure 5 , Figure 5The connection of the first electrode 332 between 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 is shown. 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] See also Figure 6 , Figure 6 The second electrodes 333 of the red light emitting chips 31, the green light emitting chips 32, and the blue light emitting chips 33 in different light emitting units 30 are connected in parallel. 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] See also Figure 7 , Figure 7 This 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 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 a driving electrode 52. The IC driving core 51 is connected to the light-emitting unit 30 through the driving electrode 52. The control chip 50 is a flip-chip. The driving electrode 52 is arranged between the IC driving core 51 and the substrate 10. The flip-chip arrangement allows the IC driving core 51 to be directly connected to the circuit of the substrate 10 through the driving electrode 52, and does not require bonding conductive wires for connection, thereby omitting the use of conductive wires and reducing production costs.

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

[0046] The two filter capacitors 60 are respectively connected in series between the two signal input electrodes of the control chip 50 and the external signal source, and are used to filter out 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 to reduce voltage fluctuations, maintain the stability of the voltage input, and prevent the control chip 50 from being damaged.

[0048] See also 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 which 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 the photoelectric conversion, the blue light emitting chip 33 can also be used as an example to replace the description at the angle of the cross section. At this time, there is no need to consider the other light emitting chips, reducing the duplication 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 minimum line spacing in the circuit layer 20. Under this setting, the light emitting unit 30 and the control chip 50 can be simultaneously bonded on the substrate 10 by hot melting of solder paste, and only one bonding operation is required, which is simple in process and low in cost; but limited by the line spacing of the circuit layer 20, the device size is large.

[0049] See also Fig. 9 In another embodiment, the light emitting unit 30 and the control chip 50 are arranged on two different layers. Fig. 9 Shown with Figure 8 With the same cross section, 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. Under this setting, there is no need to consider the line spacing of the circuit layer 20, and the device size only depends on the size of the control chip 50 itself, so the device size can reach the level of P≤0.5 (500μm); but under this setting, the light-emitting unit 30 needs to be bonded before the control chip 50, which increases 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 best implementation effect.

[0050] In particular, see Fig.10 When multiple display devices are connected together, adjacent display devices can be connected in parallel through the third wiring layer 23. Specifically, the voltage source electrodes of the 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 that Fig.10 Only the setting situation in which the connection direction of the control units in different display devices is perpendicular to the connection direction of the light-emitting units in each display device is shown. In fact, the connection direction of the control units in different display devices and the connection direction of the light-emitting units in each display device can also be parallel or located in a three-dimensional vertical structure on different planes. The specific installation needs to be adjusted according to actual needs, and it has a wide range of applications.

[0051] In addition, the present invention further provides a display device, including a driver and a plurality of the display devices described above, wherein the plurality of display devices are electrically connected to each other via conductive wires, and the driver is connected to the display devices via conductive wires.

[0052] See also Fig.11 In one embodiment, adjacent display devices are electrically connected in sequence along a direction perpendicular to the connection direction between different light-emitting units 30, and the driver is installed on the top or bottom of the display device, so that the entire display device forms a longitudinal design, which is suitable for the user's use environment with high height conditions and low width conditions.

[0053] See also Fig.12 In another embodiment, adjacent display devices are electrically connected in sequence along a direction parallel to the connection direction between different light-emitting units 30, and the driver is installed on the left or right side of the display device. The entire display device forms a horizontal design, which is suitable for the user's use environment where the width condition is high and the height condition is low. It can be understood that the display device of the present invention does not limit which specific installation method is adopted, and the user can choose according to actual needs. It has a wide range of applications and strong practicality.

[0054] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and the present invention is also intended to include these modifications and modifications.

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 solid-chip on the substrate, and each light-emitting unit includes multiple light-emitting chips of different light colors. The first electrode of each light-emitting chip of different light colors in each light-emitting unit is connected in parallel to an electrode corresponding to the control chip through the first circuit layer; and the second electrode of each light-emitting unit is connected to the electrode corresponding to the control chip through the second circuit layer.

2. The display device according to claim 1, characterized in that: The second electrodes of the light-emitting chips of the same light color between different light-emitting units are respectively connected in parallel to a corresponding electrode of the control chip through the second circuit layer.

3. The display device according to claim 2, 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.

4. The display device according to claim 2, characterized in that: The light emitting unit and the control chip are mounted on different surfaces of the substrate.

5. The display device according to claim 3 or 4, 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.

6. The display device according to claim 5, 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.

7. The display device according to claim 6, 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.

8. The display device according to claim 7, 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.

9. The display device according to claim 7, 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.

10. The display device according to claim 8 or 9, 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.

11. The display device according to claim 8 or 9, 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.

12. 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 11, wherein the driver is connected to the plurality of display devices to control display changes of the display devices.

13. The display device according to claim 12, 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.

14. The display device according to claim 12, 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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