A display driver chip integrated with a camera function, a substrate packaging structure and a method

Abstract

The present invention discloses a display driving chip and substrate packaging structure and method integrated with a camera function, which adopts a display touch control driving chip integrated with a camera function, matches a flexible packaging substrate integrating camera driving pins and display touch control driving pins, packages the flexible packaging substrate and the driving chip, punches the outer shape of the packaging substrate and punches positioning holes for assembling the camera module, bonds and connects the positions of the display touch control driving pins on the packaging substrate with the ITO pins on the display panel; bends the positions of the display touch control driving pins on the flexible packaging substrate and then assembles the camera module, and fixes the assembled camera at the camera opening position on the display screen; after the flexible packaging substrate is connected to the main control board, the display touch control driving of the display screen and the driving connection of the front camera can be completed through the CTDDI driving chip. The present invention can effectively reduce the cost of terminal products, save space on the main control board, and form a market competition advantage.

Description

Technical Field

[0001] The present invention relates to a display driving chip integrated with a camera function, a substrate packaging structure and method, belonging to the field of semiconductor technology. Background Art

[0002] Currently, full-screen smartphones have become the mainstream in the market. High screen-to-body ratio and high appearance are the key development directions of current full-screen mobile phones. Using a front camera with a hole in the screen is the main solution to increase the screen-to-body ratio of mobile phones. After the flexible printed circuit board for driving the camera is assembled with the camera module, it is connected to the main control board of the smart phone through the connection terminals on the flexible printed circuit board; for the display driving of the display screen, it is usually achieved by connecting the flexible packaging substrate encapsulated with the TDDI driving chip to the ITO pins on the screen, that is, the COF technology.

[0003] Taking the COF products widely used in full-screen smartphones as an example, the display driving principle and the connection steps of the front camera of the mobile phone are as follows:

[0004] 1) The display screen structure design of the full-screen smart phone is as Figure 1 shown. The display driving signal is received through the ITO pins 1 provided at the edge of the display panel 2 to realize the display of the image in the display area 3. Usually, the front camera opening area 4 is set in the middle or on both sides above the mobile phone screen;

[0005] 2) The COF flexible packaging substrate uses a flexible polyimide film 6 as the carrier material, forms the circuit and prints the solder resist protection ink 7 to realize the electrical interconnection between the driving chip 8 and the display panel; bond the pins in the chip bonding area of the TDDI driving chip to the pins of the COF flexible packaging substrate product. The structure of the COF flexible packaging substrate product after the display driving chip is encapsulated is as Figure 2 shown;

[0006] 3) Assemble the flexible printed circuit board 10 for connecting the camera 15 with the camera module 12. Connection terminals 11 are provided on the flexible printed circuit board 10 for connecting to the main control board of the mobile phone. Its structural schematic diagram is as Figure 3 shown;

[0007] 4) Connect the Figure 1 ITO pins 1 of the display panel 2 in Figure 2The middle output terminal pin 5 is bonded and connected. The input end side of the COF flexible packaging substrate 13 is bent to the back of the display panel 2. The input end of the COF flexible packaging substrate 13 is used to connect to the main control board of the mobile phone; Align the lens position of the camera module 12 assembled in the above step 3) with the front camera opening area 4 on the screen in the above step 1) and fix it on the back of the screen. It can be connected to the main control board through the connection terminal 11 on the flexible circuit board 10. The structural schematic diagram is as Figure 4 shown.

[0008] The above solution has the following problems:

[0009] 1. A dedicated flexible circuit board needs to be set for the front camera for driving connection, which occupies valuable internal space of the mobile phone and is not conducive to the development of smart phones towards being thinner and lighter.

[0010] 2. A flexible circuit board needs to be set for the front camera to connect to the main control board, which will occupy valuable space on the main control board and is not conducive to reducing the volume of the main control board.

[0011] 3. The front camera adopts a split plug-and-play connection design, which is not conducive to the general trend of the future development of mobile phones towards the integration of internal components. Summary of the Invention

[0012] In view of the problems existing in the above-mentioned prior art, the present invention provides an integrated camera function display driver chip and substrate packaging structure and method.

[0013] In order to achieve the above object, an integrated camera function display driver chip and substrate packaging method adopted by the present invention includes the following steps:

[0014] S1. Set the camera opening area on the same side of the ITO pins on the display panel;

[0015] S2. Integrate the camera driving function in the traditional TDDI driver chip and set the camera driving pads to form a CTDDI driver chip. At the same time, design a COF flexible packaging substrate containing camera driving pins, and set the camera driving pins and display touch driving pins in different regions on the COF flexible packaging substrate. Conduct line forming and print solder mask protection ink. Expose the input and output pins set at the bonding area of the CTDDI driver chip and both ends of the product, and bond and connect the pins of the CTDDI driver chip to the pins of the chip bonding area on the COF flexible packaging substrate product;

[0016] S3. Attach a heat dissipation reinforcement sheet to the base material surface of the COF flexible packaging substrate after the driver chip bonding is completed, and the attachment area covers the back of the driver chip;

[0017] S4. Perform contour blanking on the COF flexible packaging substrate. The blanking positions include the product contour and the positioning holes near the camera driving pins.

[0018] S5. Connect the display touch driving pins of the COF flexible packaging substrate to the ITO pins on the display panel. One side of the input terminal pins of the COF flexible packaging substrate is bent to the back of the display panel glass.

[0019] S6. After bending the part of the camera driving pin area of the COF flexible packaging substrate, use the punched positioning holes for alignment and assembly with the camera module.

[0020] S7. Align the assembled camera module with the camera opening area on the display panel and then fix it.

[0021] As an improvement, the number of camera driving pins on the COF flexible packaging substrate in step S2 is 1 - 3.

[0022] As an improvement, the attaching area of the heat dissipation reinforcement sheet in step S3 also includes the back of the camera driving pins.

[0023] As an improvement, the camera driving pin area and the display touch driving pin area are blanked into a separated state in step S4.

[0024] As an improvement, the display touch driving pins and the ITO pins are connected by pressure bonding in step S5.

[0025] In addition, the present invention also provides an integrated camera function display driver chip and substrate packaging structure obtained by the above method.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] 1. The COF flexible packaging substrate with a brand - new and original CTDDI chip matching design adopted by the present invention can replace the original two devices of the COF flexible packaging substrate for display touch and the flexible packaging substrate for camera connection. There is no need to set a dedicated flexible packaging substrate for the camera, which can effectively reduce the overall cost of the terminal product.

[0028] 2. The present invention does not need to independently set the terminals and their fixing devices for connecting the front - facing camera on the main control board, realizing the integrated connection of display, touch, and front - facing camera, saving the space on the main control board, and making the smart phone develop towards being thinner and lighter to form a market competitive advantage.

[0029] 3. The present invention integrates three high - speed signals of camera, display, and touch to the brand - new CTDDI driver chip end, replacing the original scheme that the high - speed driving signal of the camera is transmitted to the SOC on the main control board through a flexible circuit board.

[0030] 4. The present invention uses a CTDDI (Camera Touch and Display Driver Integration) driver chip and sets up pads for camera driving to drive and connect. The digital signal converted by the camera module is directly converted and transmitted to the display panel for image display. The transmission distance of the image signal is short, and the signal crosstalk is small, greatly improving the transmission rate of the image signal and the display accuracy of the captured image. This CTDDI driver chip can replace the existing TDDI chip that requires the CPU to convert and transmit the image signal. Its driving principle is as Figure 18 shown. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic structural diagram of an existing display panel;

[0032] Figure 2 is a schematic structural diagram of an existing display driver chip after encapsulation;

[0033] Figure 3 is a schematic structural diagram of an existing flexible printed circuit board;

[0034] Figure 4 is a schematic installation diagram of an existing COF flexible packaging substrate;

[0035] Figure 5 is a schematic structural diagram of the display panel of the present invention;

[0036] Figure 6 is a schematic structural diagram of the COF flexible packaging substrate of the present invention;

[0037] Figure 7 is a schematic structural diagram of the heat dissipation reinforcement sheet of the present invention;

[0038] Figure 8 is a punching schematic diagram of the COF flexible packaging substrate of the present invention;

[0039] Figure 9 is a bonding connection schematic diagram of the present invention;

[0040] Figure 10 is a schematic assembly diagram of the camera module of the present invention;

[0041] Figure 11 is a schematic structural diagram of the assembled camera module of the present invention;

[0042] Figure 12 is a schematic camera fixing diagram of the present invention;

[0043] Figure 13 is a schematic structural diagram of the present invention;

[0044] Figure 14 Schematic diagram of the COF flexible packaging substrate in the second embodiment of the present invention;

[0045] Figure 15 Schematic diagram of the assembled COF flexible packaging substrate in the second embodiment of the present invention;

[0046] Figure 16 Schematic diagram of the COF flexible packaging substrate in the third embodiment of the present invention;

[0047] Figure 17 Schematic diagram of the assembled COF flexible packaging substrate in the third embodiment of the present invention;

[0048] Figure 18 Schematic diagram of the CTDDI driving chip in the present invention;

[0049] In the figure: 1. ITO pin, 2. Display panel, 3. Display area, 4. Front camera opening area, 5. Output terminal pin, 6. Flexible polyimide film, 7. Solder mask protection ink, 8. Driving chip, 9. Input terminal pin, 10. Flexible circuit board, 11. Connection terminal, 12. Camera module, 13. COF flexible packaging substrate, 14. Connection part, 15. Camera, 16. Camera opening area, 17. Display touch driving pin, 18. First camera driving pin, 19. CTDDI driving chip, 20. Heat dissipation reinforcement sheet, 21. Positioning hole, 22. Front camera, 23. Second camera driving pin, 24. Rear camera, 25. Third camera driving pin. Detailed implementation manners

[0050] To make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below. However, it should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the scope of the present invention.

[0051] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0052] Embodiment 1

[0053] Taking the installation method of the front camera of a full-screen smart phone adopting the present invention as an example.

[0054] An installation method of a display driving and packaging substrate integrated with a camera function, comprising the following steps:

[0055] S1. Set the ITO pins 1 of the display panel 2 for the smartphone on the same side as the camera opening area 16, that is, in the upper area of the mobile phone screen. The structural design of the display panel is as Figure 5 shown;

[0056] S2. Design a new COF flexible packaging substrate 13 with a camera driving pin one 18, and set the camera driving pin one 18 and the display touch driving pins 17 in different areas on the COF flexible packaging substrate 13 to prevent driving signal crosstalk. Conduct circuit forming and print solder mask protection ink 7. Expose the input and output pins set at both ends of the product and the driving chip bonding area. Bond and connect the CTDDI driving chip 19 and the pins on the COF flexible packaging substrate 13 product at the connection part 14. The structural design of the COF flexible packaging substrate 13 integrating the camera driving pin one 18 and the display touch driving pins 17 is as Figure 6 shown;

[0057] S3. Attach a heat dissipation and reinforcement sheet 20 to the substrate surface of the COF flexible packaging substrate 13 after completing the driving chip bonding. The attachment area covers the back of the driving chip, which can play a role in assisting heat dissipation; the attachment area should also include the back of the camera driving pins, which can play a role in reinforcement. Its structure is as Figure 7 shown;

[0058] S4. Conduct shape blanking on the COF flexible packaging substrate 13. The blanking positions include the product shape and the positioning holes 21 near the camera driving pin one 18. Among them, the camera driving pin area and the display touch driving pin area should be blanked into a separated state. Its structure is as Figure 8 shown;

[0059] S5. Figure 6 Perform pressure bonding and connection between the display touch driving pins 17 of the COF flexible packaging substrate 13 shown in Figure 5 and the ITO pins 1 on the display panel 2 shown in Figure 9 shown. Bend one side of the input pins 9 of the COF flexible packaging substrate 13 to the back of the display panel glass. Its structure is as shown;

[0060] S6. After bending the camera driving pin area part of the COF flexible packaging substrate 13, use the positioning holes 21 blanked in the above step S4 for alignment and assembly with the camera module 12. The state during assembly is as Figure 10 shown;

[0061] S7. According to the description in the above step S6, the structure of the COF flexible packaging substrate 13 after completing the assembly of the front camera 22 is as Figure 11 shown;

[0062] S8. After aligning the assembled camera module 12 with the camera opening area 16 on the display panel 2, fix them. The installation structure on the back of the display screen is as Figure 12 shown, and the installation structure on the front of the display panel 2 is as Figure 13 shown; through the CTDDI driving chip 19 and the newly designed COF flexible packaging substrate 13, the display touch control and the integrated driving of the front camera of the smartphone screen can be realized.

[0063] Embodiment 2

[0064] Take the installation method of the present invention for the front camera and the rear camera of a smartphone as an example.

[0065] An installation method of a display driving packaging substrate integrated with a camera function includes the following steps:

[0066] 1) Newly design a COF flexible packaging substrate with two camera driving pins, and set the camera driving pin 18, the camera driving pin 23, and the display touch control driving pin 17 in different regions on the COF flexible packaging substrate 13 to prevent driving signal crosstalk. Carry out line forming and print the solder mask protection ink 7, expose the input and output pins set at the driving chip bonding area and both ends of the product, and bond and connect the CTDDI driving chip 19 with the pins on the COF flexible packaging substrate 13 product. The structural design of the COF flexible packaging substrate 13 integrating the two camera driving pins and the display touch control driving pin 17 is as Figure 14 shown;

[0067] 2) Repeat steps S4 to S8 in Embodiment 1 to assemble the COF flexible packaging substrate 13 with the cut-out product shape and bonded to the display panel 2 with the front camera 22 and the rear camera 24, where the front camera 22 is assembled and connected to the camera driving pin 18, and the rear camera 24 is assembled and connected to the camera driving pin 23, and fix the position after bending. The structural state of the COF flexible packaging substrate after completing the camera assembly is as Figure 15 shown.

[0068] Embodiment 3

[0069] Take the installation method of the present invention for the front camera and the rear dual cameras of a smartphone as an example.

[0070] An installation method of a display driving packaging substrate integrated with a camera function includes the following steps:

[0071] 1) A novel COF flexible packaging substrate with three camera driving pins is designed. The camera driving pin 18, camera driving pin 23, camera driving pin 25, and display touch driving pin 17 are set in different regions on the COF flexible packaging substrate 13 to prevent driving signal crosstalk. Circuit forming is carried out and solder mask protection ink 7 is printed. The input and output pins set are exposed at the driving chip bonding region and both ends of the product. The CTDDI driving chip 19 is bonded to the pins on the COF flexible packaging substrate 13 product. The structural design of the COF flexible packaging substrate 13 integrating three camera driving pins and the display touch driving pin 17 is as Figure 16 shown;

[0072] 2) Repeat steps S4 to S8 in Example 1 to assemble the COF flexible packaging substrate 13 with the product shape blanked and bonded to the display panel 2 with a front camera 22 and two rear cameras 24. Among them, the front camera 22 is assembled and connected to the camera driving pin 18, one rear camera 24 is assembled with the camera driving pin 23, and the other rear camera 24 is assembled and connected to the camera driving pin 25, and the position is fixed after bending. The structural state of the COF flexible packaging substrate after camera assembly is as Figure 17 shown.

[0073] The present invention adopts a display touch driving chip integrating a camera function, and matches and designs a flexible packaging substrate integrating camera driving pins and display touch driving pins. The camera driving pins and display touch driving pins are set in different regions on the packaging substrate. After the flexible packaging substrate and the driving chip are packaged, a flexible reinforcing sheet with enhanced heat dissipation ability is attached to the back; then the outer shape of the packaging substrate is blanked and positioning holes for camera module assembly are punched out. The position of the display touch driving pins on the packaging substrate is bonded to the ITO pins on the display panel. The position of the display touch driving pins on the flexible packaging substrate is bent and then the camera module is assembled, and the assembled camera is fixed at the front camera opening position on the display screen. After the flexible packaging substrate is connected to the main control board, the display touch driving of the display screen and the driving connection of the front camera can be completed through the CTDDI driving chip.

[0074] The packaging substrate of the present invention, in cooperation with the new CTDDI chip, can realize the driving of camera, display, and touch signals for terminal products, reduce the crosstalk between camera driving signals, and improve the display accuracy of the captured images. The solution in the present invention can drive one to multiple camera modules simultaneously, replacing two types of devices, namely the COF flexible packaging substrate for display touch and the flexible packaging substrate for camera connection in the original, saving the motherboard space and the internal space of the terminal product, and effectively reducing the overall cost of the product.

[0075] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for packaging a display driving chip integrated with a camera function and a substrate, characterized in that, It includes the following steps: S1. Set the camera opening area (16) on the same side of the ITO pins (1) on the display panel (2); S2. Integrate the camera driving function in a traditional TDDI driving chip and set camera driving pads to form a CTDDI driving chip (19). At the same time, design a COF flexible packaging substrate (13) with camera driving pins, and set the camera driving pins and the display touch driving pins (17) in separate areas on the COF flexible packaging substrate (13). Conduct circuit forming and print solder mask protection ink (7). Expose the input and output pins set at the bonding area of the CTDDI driving chip and both ends of the product. Bond and connect the pins of the CTDDI driving chip (19) and the CTDDI driving chip bonding area pins on the COF flexible packaging substrate (13) of the product; S3. Attach a heat dissipation and reinforcement sheet (20) to the base material surface of the COF flexible packaging substrate (13) after the driving chip bonding is completed, and the attachment area covers the back of the CTDDI driving chip; S4. Punch the shape of the COF flexible packaging substrate (13), and the punching positions include the product shape and the positioning holes (21) near the camera driving pins; among them, the camera driving pin area and the display touch driving pin area are punched into a separated state; S5. Connect the display touch driving pins (17) of the COF flexible packaging substrate (13) to the ITO pins (1) on the display panel (2), and bend one side of the input pins (9) of the COF flexible packaging substrate (13) to the back of the display panel glass; S6. After bending the part of the camera driving pin area of the COF flexible packaging substrate (13), use the punched positioning holes (21) to align and assemble with the camera module (12); S7. Align the assembled camera module (12) with the camera opening area (16) on the display panel (2) and then fix it.

2. A method for packaging a display driver chip integrated with a camera function and a substrate, characterized in that, In the step S2, the number of camera driving pins on the COF flexible packaging substrate (13) is 1 - 3.

3. A method for packaging a display driver chip integrated with a camera function and a substrate, characterized in that, In the step S3, the attachment area of the heat dissipation and reinforcement sheet (20) also includes the back of the camera driving pins.

4. A method for packaging a display driving chip integrated with a camera function and a substrate, characterized in that In the step S5, the display touch driving pins (17) and the ITO pins (1) are connected by pressure bonding.

5. A structure of an integrated camera function display driving chip and substrate packaging obtained by the method according to any one of claims 1 - 4.

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