Optimized MIPI camera and electronic equipment with same
By using flexible printed circuits and shared circuit components in the MIPI camera, combined with flexible flat cables and IO extenders, the problems of high cost and thick shaft design of the MIPI camera are solved, and the lightness and signal transmission efficiency of the equipment are improved.
Patent Information
- Application Number
- CN202420611534.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-27
- Publication Date
- 2025-03-04
- Estimated Expiration
- 2034-03-27
AI Technical Summary
Since the MIPI camera requires up to a dozen data cables to connect to the motherboard CPU, the cost is high and the shaft design is thick, which affects the lightness and thinness of the equipment. At the same time, high-speed signal transmission is limited.
Flexible printed circuit (FPC) is used as the control circuit, and equipment cost and signal transmission complexity are reduced through shared oscillators, shared I2C buses, shared voltage regulators and IO extenders. Meanwhile, a flexible flat cable (FFC) is used to replace part of the FPC, reducing the material cost of the connector and reducing the number of IO signals through the rotary shaft through the IO extender.
It realizes the reduction of the material cost of MIPI camera and the thickness of the shaft design, and improves the lightness and signal transmission efficiency of the equipment.
Smart Images
Figure CN222563872U_ABST
Abstract
Description
Technical Field
[0001] The utility model generally relates to a MIPI camera, and more specifically, to a MIPI camera capable of reducing material cost and realizing a light and thin roller design. Background Art
[0002] Most of the notebooks on the market currently use USB (Universal Serial Bus) cameras that can be connected to the motherboard CPU with only two wires. The collected image data is processed in the camera module, and then the processed image data is transmitted to the motherboard CPU for display. Unlike USB cameras, MIPI (Mobile Industry Processor Interface) cameras are only responsible for collecting images. The collected image data is transmitted to the motherboard CPU via the interface circuit, and then various processes are performed in the image processor integrated into the motherboard CPU.
[0003] Although MIPI cameras are known to reduce system power consumption and improve image quality, they require more than a dozen data cables to connect to the motherboard CPU, which is costly and makes the hinge between the laptop screen and the motherboard thicker. In addition, the distance for transmitting the collected image data from the camera module at the top of the laptop screen to the motherboard CPU via the hinge is as long as (for example) tens of centimeters, and such a long transmission distance limits the transmission of high-speed signals.
[0004] Although MIPI cameras have the above-mentioned shortcomings, due to the limited bandwidth of USB cameras, MIPI cameras are still needed for cameras above 5M. Therefore, it is desirable to provide a MIPI camera that can overcome the above-mentioned cost and shaft design challenges. Utility Model Content
[0005] According to an embodiment of the utility model, a MIPI camera is provided, comprising: a camera module, the camera module comprising two cameras; a control circuit based on the MIPI camera, the control circuit being a flexible printed circuit (FPC) and the camera module being embedded in the control circuit; and a signal transmission cable based on the MIPI camera, the signal transmission cable being connected to the control circuit, characterized in that the control circuit comprises one or more of an oscillator shared by the two cameras, a shared I2C bus, a shared voltage regulator and an IO expander, and the signal transmission cable comprises a flexible flat cable (FFC).
[0006] In some embodiments, the two cameras include one or both of an RGB MIPI camera and an infrared (IR) MIPI camera.
[0007] In some embodiments, the oscillator and the camera have a daisy chain topology.
[0008] In some embodiments, the voltage regulator provides at least one of 2.8V, 1.8V and 1.2V to the camera.
[0009] In some embodiments, when one of the two cameras is not working, a control signal is applied to the non-working camera to make it work in a low power consumption mode.
[0010] In some embodiments, when the camera comprises an IR MIPI camera, voltage is applied directly to an IR LED driver of the IR MIPI camera through an independent path.
[0011] In some embodiments, a voltage of 3.3V is directly applied to the IR LED driver.
[0012] In some embodiments, the IO expander enables only I2C bus signals to be transmitted to the mainboard.
[0013] In some embodiments, the signal transmission cable is connected to the control circuit by a connector-free soldering technique.
[0014] According to another embodiment of the utility model, a MIPI camera is provided, comprising: a camera module including a single camera; a control circuit based on the MIPI camera; and a signal transmission cable based on the MIPI camera, wherein the signal transmission cable is connected to the control circuit, characterized in that the control circuit is a flexible printed circuit and the camera module is embedded in the control circuit, and the signal transmission cable comprises a flexible flat cable.
[0015] In some embodiments, the single camera is an RGB MIPI camera or a USB camera.
[0016] In some embodiments, the signal transmission cable is connected to the control circuit by a connector-free soldering technique.
[0017] According to yet another embodiment of the present invention, an electronic device is provided, which includes the MIPI camera according to the present invention.
[0018] In some embodiments, the electronic device includes any one of a laptop computer, a tablet computer, and a mobile phone. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The accompanying drawings are incorporated herein and form a part of the specification, illustrating embodiments of the present invention and together with the description further serve to explain the principles of the present invention and enable those skilled in the relevant art to make and use the present invention.
[0020] Figure 1 A schematic plan view of a conventional laptop camera is shown;
[0021] FIG2(a) shows a block diagram of a conventional MCLK and I2C (Inter-Integrated Circuit) bus design, where there is no shared oscillator and I2C bus in the FPC of a MIPI camera;
[0022] FIG2( b ) shows a block diagram of an MCLK and I2C bus design according to an embodiment of the present invention, wherein a shared oscillator and I2C bus are provided in the FPC of a MIPI camera;
[0023] FIG3( a ) shows a conventional RGB&IR camera power design block diagram, in which there is no shared voltage regulator VR (Voltage regulators) in the FPC of the MIPI camera;
[0024] FIG3( b ) shows a block diagram of an RGB&IR camera power design according to an embodiment of the present invention, wherein a shared voltage regulator VR is provided in the FPC of the MIPI camera;
[0025] FIG4( a ) shows a conventional IR LED power design block diagram, in which a linear voltage regulator and a buck voltage regulator are used to apply voltages to a camera sensor and an IR LED driver, respectively;
[0026] FIG4( b ) shows a block diagram of an IR LED power design according to an embodiment of the present invention, wherein a voltage is applied directly from a mainboard to an IR LED driver through an independent current transmission path to remove a step-down voltage regulator for the IR LED driver;
[0027] FIG5( a ) shows a conventional RGB&IR camera control block diagram;
[0028] FIG5( b ) shows a control block diagram of an RGB & IR camera according to an embodiment of the present invention, wherein an IO expander is applied on the FPC to reduce the number of IO signals passing through the shaft; and
[0029] Figure 6 A schematic diagram showing changing the FPC pattern and applying the FFC / FPC hybrid technology according to an embodiment of the utility model is shown.
[0030] Various embodiments will be described with reference to the accompanying drawings. DETAILED DESCRIPTION
[0031] The subject matter described herein will now be discussed with reference to example implementations. It should be understood that the discussion of these implementations is only intended to enable those skilled in the art to better understand and implement the subject matter described herein, and is not intended to limit the scope of protection, applicability, or examples set forth in the claims. The functions and arrangements of the elements discussed may be changed without departing from the scope of protection of the present specification. Various examples may omit, replace, or add various processes or components as needed. In addition, the features described relative to some examples may also be combined in other examples.
[0032] It should be noted that the references to "one embodiment", "embodiment", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, such expressions do not necessarily refer to the same embodiment. In addition, when specific features, structures or characteristics are described in conjunction with an embodiment, it should be within the knowledge of technicians in the relevant field to implement such features, structures or characteristics in conjunction with other embodiments that are explicitly or not explicitly described.
[0033] The embodiments of the present invention may be described with reference to the accompanying drawings. Unless explicitly stated, the dimensions of the accompanying drawings are intended to simplify the examples rather than to describe relative dimensions. For example, the various lengths / widths / heights of the elements in the accompanying drawings may not be drawn to scale unless otherwise indicated.
[0034] An embodiment of a MIPI camera according to the present invention will now be described with reference to the accompanying drawings.
[0035] Figure 1 FIG. 1 shows a plan view of a conventional laptop camera. Figure 1 As shown in the figure, the camera module 12 located on the upper part of the screen 11 of the notebook 10 includes two MIPI cameras. In one embodiment, the two MIPI cameras can be, for example, an RGB MIPI camera and an infrared (IR) MIPI camera for video conferencing and face recognition, respectively, but the present disclosure is not limited thereto. For example, in one embodiment, the two MIPI cameras in the camera module 12 can both be RGB MIPI cameras.
[0036] like Figure 1 As shown in FIG. 1 , the camera module 12 is embedded in a control circuit 13 based on a MIPI camera and is connected to the electronic circuit in the control circuit 13 through a connector (not shown). In one embodiment, the control circuit 13 may be, for example, a flexible printed circuit, but the present disclosure is not limited thereto. Figure 1As shown in , the control circuit 13 based on the MIPI camera includes a first part 13-1 extending in the horizontal direction and a second part 13-2 extending in the vertical direction. In one embodiment, the control circuit 13 may include various components, such as an oscillator, a voltage regulator, an IR LED driver, a TOF sensor, a digital microphone, and a color ambient light sensor.
[0037] like Figure 1 As shown in FIG. 1 , the second part 13-2 of the control circuit 13 is connected to the cable 14 through a connector (not shown), and the cable 14 then passes through the shaft 15 and bypasses the fan 18 to connect to the connector 17 in the motherboard 16. When the notebook is working, the image data collected by the camera module 12 can be transmitted to the image processor in the motherboard 16 through the first part 13-1 and the second part 13-2 of the control circuit 13, the cable 14, and the connector 17. Similarly, various command signals issued from the motherboard 16 can be transmitted to the camera module 12 via the connector 17, the cable 14, the first part 13-1 and the second part 13-2 of the control circuit 13 to control the image acquisition of the camera module 12.
[0038] exist Figure 1 In the notebook shown, in addition to the image data from the camera module 12, signals from some components of the control circuit 13 (e.g., digital microphone, color ambient light sensor, etc.) are also transmitted to the mainboard 16 via the cable 14. In some embodiments, the cable 14 may, for example, include a Teflon wire composed of a single electronic wire and a plurality of coaxial wires each composed of two electronic wires wound together, wherein the Teflon wire may, for example, be used to transmit low-speed signals or power signals, and the coaxial wire may, for example, be used to transmit high-speed signals from the camera module 12. Since there are many signals to be transmitted, the cable 14 usually includes a plurality of electronic wires, which makes the shaft 15 located between the laptop screen 11 and the mainboard 16 often thicker.
[0039] In some cases, since the second portion 13-2 of the control circuit 13 is usually long, the signal passing through the second portion 13-2 may not meet the requirements if it is further transmitted through the Teflon wire in the cable 14. In this case, the cable 14 may need to include only a coaxial line with a higher cost, thereby increasing the material cost.
[0040] In addition, Figure 1 In the notebook shown in the figure, the control circuit 13 as a flexible printed circuit needs to be manufactured by a raw material having a rectangular shape consisting of a first portion 13-1 and a second portion 13-2. Since the cost of the raw material for manufacturing the flexible printed circuit is high, it is desirable to reduce the cost as much as possible. Figure 1Manufacturing costs of MIPI cameras shown.
[0041] Typically, a notebook motherboard has a platform controller hub (PCH) for providing a clock signal to a camera sensor. However, the driving length of the PCH signal in many notebooks is limited. For example, in many cases, if a clock signal is provided to a camera sensor through a PCH located in the motherboard 16, then the PCH signal is transmitted through the PCH. Figure 1 The total routing length of the cable 14 and the clock signal of the control circuit 13 (eg, FPC) may exceed the length specification that the PCH can drive (eg, more than 300 mm). Figure 1 In the control circuit 13 of the notebook 10 shown in the figure, an oscillator is separately provided as a clock source for the camera sensor. Figure 1 In the case where the camera module 12 shown has two MIPI cameras, as shown in FIG. 2( a ), two oscillators 21 , 22 are provided in the FPC, which provide clock signals MCLK for the RGB camera and the IR camera respectively.
[0042] According to an embodiment of the present invention, as shown in FIG2( b ), a single oscillator 23 is provided in the control circuit 13 , which can provide a clock signal MCLK for both the RGB camera and the IR camera. By providing a shared oscillator for the RGB camera and the IR camera, the cost can be reduced.
[0043] In addition, as shown in FIG. 2( b ), in order to reduce signal interference between the RGB camera sensor and the IR camera sensor, the oscillator 23 and the RGB camera and the IR camera may have a daisy chain topology, for example.
[0044] When the camera module 12 is working, various control signals need to be transmitted from the mainboard 16 to the camera module 12, such as a signal for identifying the camera type in the camera module 12, a signal for configuring the working parameters of the camera module 12, etc. Although it is known that the I2C bus can support the topological logic between a single master device and multiple slave devices, due to complex timing control, two I2C buses are still set in FIG. 2(a) to transmit control signals from the SoC to the corresponding camera sensors (e.g., the RGB camera sensor and the IR camera sensor) in the camera module 12, respectively.
[0045] According to an embodiment of the present invention, by analyzing and optimizing the I2C bus workload, controlling delay sensitivity and timing adjustment, Figure 1An I2C bus is set in the control circuit 13, that is, the RGB camera and the IR camera in the camera module 12 share an I2C bus, so that an I2C bus extending from the mainboard 16 to the camera module 12 can be reduced, thereby reducing the cost.
[0046] exist Figure 1 When the camera module 12 shown is working, it is necessary to provide voltage to the RGB camera and the IR camera. As shown in FIG3(a), separate voltage regulators VR1-VR6 are provided for the RGB camera and the IR camera, respectively. In one embodiment, the voltage regulators VR1-VR3 provide voltages of 2.8V, 1.8V and 1.2V for the RGB camera, respectively, and the voltage regulators VR4-VR6 provide voltages of 2.8V, 1.8V and 1.2V for the IR camera, respectively. For those skilled in the art, the voltages provided by the voltage regulators VR1-VR6 are not limited to this.
[0047] According to one embodiment of the present invention, as shown in FIG. 3( b), a shared voltage regulator VR7-VR9 is provided for the RGB camera and the IR camera, wherein the voltage regulator VR7 provides a voltage of 2.8V for the RGB camera and the IR camera, the voltage regulator VR8 provides a voltage of 1.8V for the RGB camera and the IR camera, and the voltage regulator VR9 provides a voltage of 1.2V for the RGB camera and the IR camera.
[0048] In the power design shown in FIG3( b ), when only one of the RGB camera and the IR camera is working and the other camera is not working, the non-working camera is still supplied with voltage due to the shared voltage regulator VR design. In this case, a control signal (not shown in FIG3( b )) can be provided to the non-working camera to make it work in a low power consumption mode. In one embodiment, by providing a control signal, the non-working camera of the RGB camera and the IR camera can have a power consumption of only, for example, <20 uW.
[0049] By designing a shared voltage regulator VR, the power-on and power-off timing and output voltage tolerance of the voltage regulator VR can meet the requirements of both the RGB camera and the IR camera. In addition, the shared voltage regulator VR design shown in FIG3( b ) can further reduce costs.
[0050] exist Figure 1In the case where the camera module shown includes an IR camera, the camera module includes an IR LED driver, which has a relatively large operating current. If the voltage output from the mainboard is 3.3V, a large voltage drop may occur in the current transmission path due to the long path of the cable and the control circuit (e.g., the FPC in FIG. 4(a)) and the relatively large operating current of the IR LED driver. For example, the 3.3V voltage output from the mainboard may drop to (e.g.) 2.9V. Although the 2.9V voltage enables the IR LED driver to operate normally, the voltage difference between the input and the output is too small, and the 2.8V voltage required for the camera sensor to operate may not be provided through the voltage regulator VR shown in FIG. 3(b).
[0051] To solve this problem, as shown in FIG4( a ), a 5 V voltage is output from the main board and a linear voltage regulator VR for the camera sensor is provided in the FPC. camera And a step-down voltage regulator VR for IR LED driver IR RED Even though the cable and FPC cause the voltage output from the motherboard to drop from 5V to 3.3V, it is still possible to use the voltage regulator VR camera and VR IR RED The camera sensor and IR LED driver are provided with appropriate operating voltages respectively. However, in this case, the 5V voltage output from the mainboard causes the system power consumption to increase and the voltage regulator VR IR RED The existence of will also lead to increased costs.
[0052] According to an embodiment of the present invention, as shown in FIG. 4(b), a 3.3V voltage is output from the mainboard, but unlike FIG. 4(a), voltages are provided to the camera sensor and the IR LED driver respectively through different paths. As shown in FIG. 4(b), voltage is provided directly from the mainboard to the IR LED driver through an independent current transmission path. Even if the 3.3V voltage output from the mainboard drops to, for example, 2.9V due to the large operating current of the IR LED driver, the 2.9V voltage can still enable the IR LED driver to operate normally. In addition, since the operating current of the camera sensor is small, the 3.3V voltage output through the independent current path only causes a small voltage drop in the camera sensor current transmission path, for example, down to 3.2V. In this case, through the linear voltage regulator VR for the camera sensor camera , which can provide the camera sensor with the 2.8V voltage required for its operation.
[0053] As shown in FIG4(b), the operating voltage required for the IR LED driver is directly provided from the mainboard through an independent current transmission path, and the step-down voltage regulator VR shown in FIG4(a) can be omitted. IR RED , thus reducing costs. In addition, since only 3.3V voltage is provided from the motherboard, the system power consumption can be greatly reduced.
[0054] FIG5(a) shows a conventional RGB&IR camera control block diagram, which shows some low-speed control signals transmitted between the mainboard and the camera sensor, such as RGB_Xshutdown signal, RGB_I2C_Bus signal, RGB_VR_EN signal for the RGB camera, IR_Xshutdown signal, IR_I2C_Bus signal, IR_VR_EN signal for the IR camera, IR_Strobe signal for the IR LED driver, and Indicator_CTRL signal for the indicator LED. In the case where the I2C_Bus is usually two signal lines, the method shown in FIG5(a) requires 10 electronic wires to transmit these low-speed control signals between the mainboard and the camera sensor through the shaft.
[0055] FIG5(b) shows a control block diagram of an RGB&IR camera according to an embodiment of the present invention, wherein an IO expander is applied on the FPC to reduce the number of IO signals passing through the shaft. As shown in FIG5(b), in addition to the RGB_I2C_Bus signal for the RGB camera and the IR_I2C_Bus signal for the IR camera, the other low-speed control signals shown in FIG5(a) are input to an IO expander and the output of the IO expander is also connected to the mainboard via the IO Expender_I2C_Bus bus. In addition, as shown in FIG5(b), the RGB camera and the IR camera can utilize the shared I2C bus as shown in FIG2(b) and the IO Expender_I2C_Bus bus connected to the IO expander also reuses the shared I2C bus.
[0056] In this way, while the I2C_Bus usually has two signal lines, the design shown in Figure 5(b) only needs two electronic wires to transmit the low-speed control signal between the motherboard and the camera sensor through the hinge, thereby realizing a light and thin hinge design.
[0057] Figure 6 A schematic diagram showing changing the FPC pattern and applying the FFC / FPC hybrid technology according to an embodiment of the utility model is shown. Figure 6, a conventional FPC design having an L shape and a T shape is shown in FIG. In the case where the FPC has an L shape and a T shape, the manufacturing cost of the FPC will be determined by the raw material having a rectangular shape covering the L shape and the T shape. Due to this low area utilization, the FPC cost is very high.
[0058] According to an embodiment of the present invention, the use of FFC / FPC hybrid technology can greatly reduce costs. Figure 6 As shown in the figure, the part extending in the vertical direction in the L-shape and T-shape shown on the left is replaced by FFC. Since the cost of FFC is much lower than that of FPC, the hybrid FFC / FPC solution will greatly reduce the cost. In the FFC / FPC hybrid technology, although the shape of the FPC extending in the horizontal direction is still rectangular, since it only needs to cover a rectangular shape of raw materials extending in the horizontal direction, its area utilization is much higher than the design on the left.
[0059] For high-speed signal transmission, FFC has better electrical signal insertion loss. With the same length, the insertion loss of FFC is only one-third of that of FPC, which can support longer high-speed signal trace lengths or obtain higher signal insertion loss margins. In addition, FFC can be connected to FPC or cables through connector-free welding technology, thus eliminating the material cost of the connector.
[0060] According to the MIPI camera of the utility model, the cost of the device can be greatly reduced by using one or more of a shared oscillator, a shared I2C bus, a shared voltage regulator, and an IO expander for two cameras, and replacing part of the FPC with an FFC. In addition, the use of the IO expander greatly reduces the number of signals transmitted between the camera module and the mainboard through the shaft, thereby achieving a light and thin shaft design.
[0061] It should be noted that not all units in the above-mentioned devices are necessary, and some units may be ignored according to actual needs. The device structure described in the above-mentioned embodiments may be a physical structure or a logical structure, that is, some units may be implemented by the same physical entity, or some units may be implemented by multiple physical entities, or may be implemented by some components in multiple independent devices.
[0062] The above description of the utility model is provided to enable any person of ordinary skill in the art to implement or use the disclosure. Various modifications to the utility model will be apparent to those of ordinary skill in the art, and the general principles defined in the utility model may be applied to other variations without departing from the scope of protection of the utility model. Therefore, the utility model is not limited to the examples and designs described herein, but is consistent with the widest range of principles and novel features disclosed herein.
Claims
1. A MIPI camera, comprising: A camera module, wherein the camera module includes two cameras; A control circuit based on a MIPI camera, wherein the control circuit is a flexible printed circuit and the camera module is embedded in the control circuit; as well as A signal transmission cable based on a MIPI camera, wherein the signal transmission cable is connected to the control circuit, It is characterized in that the control circuit includes one or more of a shared oscillator, a shared I2C bus, a shared voltage regulator and an IO expander for the two cameras, and the signal transmission cable includes a flexible flat cable.
2. The MIPI camera according to claim 1, characterized in that: The two cameras include one or both of an RGB MIPI camera and an infrared (IR) MIPI camera.
3. The MIPI camera according to claim 1, characterized in that: The oscillator and the camera have a daisy chain topology.
4. The MIPI camera according to claim 1, characterized in that: The voltage regulator provides at least one of voltages of 2.8V, 1.8V, and 1.2V to the camera.
5. The MIPI camera according to claim 4, characterized in that: When one of the two cameras is not working, a control signal is applied to the non-working camera to make it work in a low power consumption mode.
6. The MIPI camera according to claim 1, characterized in that: When the camera includes an IR MIPI camera, a voltage is directly applied to an IR LED driver of the IR MIPI camera through an independent path.
7. The MIPI camera according to claim 6, characterized in that: A voltage of 3.3V is applied directly to the IR LED driver.
8. The MIPI camera according to claim 1, characterized in that: The IO expander enables only the I2C bus signals to be transmitted to the main board.
9. The MIPI camera according to claim 1, characterized in that: The signal transmission cable is connected to the control circuit by a connector-free welding technique.
10. A MIPI camera, comprising: A camera module including a single camera; Control circuit based on MIPI camera; as well as A signal transmission cable based on a MIPI camera, wherein the signal transmission cable is connected to the control circuit, It is characterized in that the control circuit is a flexible printed circuit and the camera module is embedded in the control circuit, and the signal transmission cable includes a flexible flat cable.
11. The MIPI camera according to claim 10, characterized in that: The single camera is an RGB MIPI camera or a USB camera.
12. The MIPI camera according to claim 10, characterized in that: The signal transmission cable is connected to the control circuit by a connector-free welding technique.
13. An electronic device comprising the MIPI camera according to any one of claims 1-12.
14. The electronic device according to claim 13, characterized in that: The electronic device includes any one of a notebook computer, a tablet computer, and a mobile phone.