WO2024066953A1

WO2024066953A1 - Ppg module, manufacturing method therefor, and electronic device

Info

Publication number: WO2024066953A1
Application number: PCT/CN2023/116959
Authority: WO
Inventors: 王雅楠; 丁才华; 郭学平; 白亮; 朱建伟
Original assignee: 荣耀终端有限公司
Priority date: 2022-09-30
Filing date: 2023-09-05
Publication date: 2024-04-04
Also published as: CN117838073A

Abstract

Embodiments of the present application relate to the technical field of electronic devices, and provide a PPG module, a manufacturing method therefor, and an electronic device, which can solve the problem that the number of devices capable of being arranged in a PPG module in related technologies is limited. The PPG module comprises: a circuit board, as well as a light-emitting element, a photoelectric sensor, a first device and a blocking part which are arranged on a first surface of the circuit board. The blocking part is configured for shielding light. At least a portion of the blocking part is located between the light-emitting element and the photoelectric sensor. The first device is embedded inside the blocking part. The present application can be applied to an electronic device such as a smartwatch.

Description

A PPG module and its manufacturing method, and electronic equipment

This application claims the priority of the Chinese patent application filed with the State Intellectual Property Office on September 30, 2022, with application number 202211213008.7 and application name “A PPG module, its manufacturing method, and electronic device”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the technical field of electronic equipment, and in particular to a PPG module and a manufacturing method thereof, and an electronic device.

Background technique

PPG (Photoplethysmography) technology is a non-invasive detection method that uses photoelectric means to detect changes in blood volume in living tissues. It can be used to detect target parameters such as heart rate, blood pressure, and blood oxygen saturation. At present, PPG modules made based on PPG technology have been integrated into electronic devices such as smart watches and wristbands to achieve the purpose of continuous monitoring. Among them, how to design and make PPG modules has become an important topic in the industry.

The PPG module in the related art includes a first sub-board, a second sub-board, a light-emitting element, a photoelectric sensor, a barrier and a device, wherein the light-emitting element, the photoelectric sensor and the barrier are arranged on the first sub-board, and the barrier is arranged between the light-emitting element and the photoelectric sensor. The second sub-board is stacked with the first sub-board, and the device is arranged on the second sub-board.

In the related art, the PPG module occupies a certain area because the barrier portion is disposed on the first sub-board, which squeezes the layout space of other devices, resulting in low area utilization on the first sub-board, thereby limiting the number of devices that can be arranged in the PPG module.

Summary of the invention

The embodiments of the present application provide a PPG module and a manufacturing method thereof, and an electronic device, which are used to solve the problem that the number of devices that can be arranged in the PPG module of the related art is limited.

To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

In a first aspect, an embodiment of the present application provides a PPG module, comprising: a circuit board, and a light-emitting element, a photoelectric sensor, a first device and a barrier portion arranged on a first surface of the circuit board, the barrier portion being used to block light and at least partially located between the light-emitting element and the photoelectric sensor, and the first device being embedded in the interior of the barrier portion.

By adopting the above technical solution, by embedding the first device inside the barrier portion, the first device can make full use of the area on the first surface of the circuit board covered by the barrier portion, thereby helping to improve the area utilization rate of the first surface of the circuit board, so that more area can be freed up on the circuit board to arrange more devices, thereby increasing the number of devices that can be arranged in the PPG module.

In some embodiments, the first device includes at least one of a first chip, a first passive device, and a magnetic member capable of generating magnetic attraction; wherein the first passive device includes at least one of an inductor, a resistor, and a capacitor.

By adopting the above technical solution, the area of the first surface covered by the barrier portion can be utilized to the maximum extent, so that more space can be freed up on the second surface of the circuit board to arrange more devices.

In some embodiments, the first device includes a plurality of first chips, and at least a portion of the first chips are bare chips.

By adopting the above technical solution, the barrier portion can protect the bare chip, and the bare chip does not need to be packaged, which is beneficial to reducing costs.

In some embodiments, the first chip and the first passive component are disposed in an edge region of the first surface.

By adopting the above technical solution, the probability of position interference between the first chip, the first passive component and the light-emitting element or the photoelectric sensor in the central area of the first surface is reduced.

In some embodiments, the magnetic member is disposed in a central area of the first surface.

By adopting the above technical solution, electronic devices can be more easily balanced during wireless charging and are less likely to deflect.

In some embodiments, there are multiple photoelectric sensors and multiple light-emitting elements, and the multiple light-emitting elements and the multiple photoelectric sensors are alternately arranged along the circumference of the circuit board to form a first array; one photoelectric sensor and multiple magnetic members are provided on the inner side of the first array, and the multiple magnetic members are arranged around the photoelectric sensor located on the inner side of the first array.

By adopting the above technical solution, the magnetic member can more fully utilize the gap between the photoelectric sensor located on the inner side of the first array and the first array, and also make it easier for the electronic device to maintain balance during wireless charging.

In some embodiments, at least one of the first chips is an analog front-end processing chip, which is electrically connected to the light-emitting element and the photoelectric sensor, and is used to drive the light-emitting element to emit light and convert the photocurrent signal emitted by the photoelectric sensor into a voltage signal.

By adopting the above technical solution, the length of the path for electrically connecting the analog front-end processing chip with the light-emitting element and the photoelectric sensor can be shortened.

In some embodiments, a height of the first component is smaller than a height of the barrier portion.

By adopting the above technical solution, the first device can be completely embedded in the interior of the barrier portion, thereby avoiding the increase in the thickness of the PPG module caused by the first device extending out of the upper surface of the barrier portion (the side surface close to the back cover).

In some embodiments, the PPG module further includes a second device, the height of the second device is less than the thickness of the circuit board, and the second device is embedded in the interior of the circuit board.

By adopting the above technical solution, the second device can be completely embedded in the interior of the circuit board, thereby reducing the surface space occupied by the second device on the circuit board, and avoiding the increase in the thickness of the PPG module caused by the second device extending out of the surface of the circuit board.

In some embodiments, the second device is an analog front-end processing chip, which is electrically connected to the light-emitting element and the photoelectric sensor and is used to drive the light-emitting element to emit light and convert the photocurrent signal emitted by the photoelectric sensor into a voltage signal.

In some embodiments, the second device and the first device are disposed on the same circuit board.

By adopting the above technical solution, the structure of the circuit board can be made more compact, which is beneficial to reduce PPG The thickness of the module.

In some embodiments, the material of the barrier portion is epoxy molding compound.

By adopting the above technical solution, the heat dissipation effect of embedding the first device in the baffle is better than air heat dissipation, so that the temperature of the first device can be effectively controlled not to be too high.

In a second aspect, an embodiment of the present application provides an electronic device, comprising a housing, and the PPG module described in the first aspect, wherein the PPG module is disposed in the housing.

The electronic device in the embodiment of the present application has the same technical effect as that achieved by the PPG module in the first aspect, which will not be repeated here.

In a third aspect, an embodiment of the present application provides a method for manufacturing a PPG module, comprising: setting a first device on a first surface of a circuit board; setting a barrier portion for blocking light on the first surface, so that the first device is embedded in the interior of the barrier portion, and at least a portion of the barrier portion is located between a first area and a second area of the first surface; setting a light-emitting element in the first area, and setting a photoelectric sensor in the second area.

The manufacturing method of the PPG module in the embodiment of the present application has the same technical effect as that achieved by the PPG module in the first aspect, and will not be repeated here.

In some embodiments, a blocking portion for blocking light is provided on the first surface so that the first device is embedded in the interior of the blocking portion, including: placing the circuit board in the mold cavity of the lower mold; closing the upper mold with the lower mold to form a accommodating cavity for accommodating the first device between the upper mold and the circuit board; injecting a light-shielding material into the accommodating cavity to cover the first device, and demolding the light-shielding material after it is cooled to form the blocking portion.

By adopting the above technical solution, the barrier part can be made into various shapes by adjusting the shape of the cavity of the upper mold to meet the requirements of embedding first devices of different shapes. At the same time, after the barrier part is formed, it is not necessary to process the barrier part extensively, thus reducing the damage to the circuit board caused by subsequent processing.

In some embodiments, after placing the circuit board in the mold cavity of the lower mold and before closing the upper mold with the lower mold, it also includes: covering the first area and the second area with a protective layer for contacting the upper mold.

By adopting the above technical solution, it is possible to avoid direct contact between the upper mold and the first area and the second area of the circuit board to damage the circuit board.

In some embodiments, before arranging the first device on the first surface of the circuit board, the method further includes: embedding a second device inside the circuit board; wherein the height of the second device is less than the thickness of the circuit board.

In some embodiments, embedding a second device inside the circuit board includes: embedding the second device on a first dielectric layer so that a conductive portion of the second device is exposed from a surface of the first dielectric layer; stacking a second dielectric layer on the first dielectric layer so that the second dielectric layer covers the second device, and making a circuit electrically connected to the conductive portion on the second dielectric layer; wherein the circuit board includes the first dielectric layer and the second dielectric layer.

By adopting the above technical solution, the impact on the circuits inside the circuit board is relatively small.

In some embodiments, the second device is embedded in the first dielectric layer so that the conductive portion of the second device is exposed from the surface of the first dielectric layer, including: opening a receiving groove on the first dielectric layer that penetrates the first dielectric layer; stacking a carrier film bonded with the second device on the first dielectric layer so that the second device is located in the receiving groove; wherein a side of the second device provided with the conductive portion is bonded to the carrier film; filling the receiving groove with insulating material from a notch on a side of the receiving groove away from the carrier film; and separating the carrier film from the second device so that the conductive portion of the second device is exposed from the surface of the first dielectric layer.

By adopting the above technical solution, the gap between the receiving groove and the second device can be eliminated by filling the insulating material in the receiving groove, thereby preventing the second device from shaking in the receiving groove. The carrier film bonded with the second device is stacked on the first dielectric layer, so that the conductive part of the second device can be located at the notch of the receiving groove, so as to facilitate the subsequent electrical connection between the circuit on the second dielectric layer and the conductive part.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of a PPG module in the related art;

FIG2 is a schematic diagram of the structure of a smart watch in some embodiments of the present application;

FIG3 is a schematic diagram of the connection between the PPG module and the back cover in the first embodiment of the present application;

FIG4 is a structural block diagram of a PPG module in some embodiments of the present application;

Fig. 5 is a cross-sectional view taken along line A-A of Fig. 3;

FIG6 is a top view of FIG3 without the rear cover and the baffle;

FIG7 is a schematic diagram of the connection between the PPG module and the back cover in the second embodiment of the present application;

FIG8 is a top view of FIG7 after removing the rear cover and the barrier portion;

FIG9A is a schematic diagram of the connection between the PPG module and the back cover in the third embodiment of the present application;

FIG9B is a top view of FIG9A after removing the rear cover and the barrier portion;

FIG10 is a flowchart of manufacturing a PPG module in some embodiments of the present application;

FIG. 11A is a first schematic diagram of a manufacturing process of a PPG module in some embodiments of the present application;

FIG. 11B is a second schematic diagram of the manufacturing process of the PPG module in some embodiments of the present application;

FIG11C is a third schematic diagram of the manufacturing process of the PPG module in some embodiments of the present application;

FIG11D is a fourth schematic diagram of the manufacturing process of the PPG module in some embodiments of the present application;

FIG11E is a fifth schematic diagram of the manufacturing process of the PPG module in some embodiments of the present application;

FIG11F is a sixth schematic diagram of the manufacturing process of the PPG module in some embodiments of the present application;

FIG11G is a seventh schematic diagram of the manufacturing process of the PPG module in some embodiments of the present application;

FIG12A is a schematic diagram 1 of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12B is a second schematic diagram of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12C is a third schematic diagram of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12D is a fourth schematic diagram of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12E is a fifth schematic diagram of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12F is a sixth schematic diagram of the manufacturing process of the PPG module in other embodiments of the present application;

FIG12G is a seventh schematic diagram of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12H is a schematic diagram 8 of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12I is a ninth schematic diagram of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12J is a schematic diagram 10 of the manufacturing process of the PPG module in some other embodiments of the present application;

FIG12K is a schematic diagram 11 of the manufacturing process of the PPG module in other embodiments of the present application.

Detailed ways

In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

Heart function can reveal a lot of valuable information about the human body, including health status, lifestyle, even emotional state and early onset of heart disease. In traditional medical equipment, monitoring heart rate and heart activity is done by measuring electrophysiological signals and electrocardiogram (ECG). Electrodes need to be connected to the body to measure the signals of electrical activity caused by heart tissue. Monitoring is inconvenient and the cost of monitoring equipment is high. Therefore, PPG technology came into being.

PPG technology is a non-invasive detection method that uses photoelectric means to detect changes in blood volume in living tissues. Its principle is: when the light-emitting element emits a light beam of a certain wavelength to illuminate the skin surface of the measured part (such as the wrist), the contraction and expansion of the blood vessels will affect the transmission of light every time the heart beats. When the light passes through the skin tissue and then reflects to the photoelectric sensor, the light will be attenuated to a certain extent. The absorption of light by muscles, bones, veins and other connecting tissues is basically unchanged (provided that the measured part does not move significantly), but arteries are different. Since there is blood pulsation in the arteries, the absorption of light will naturally change. When the photoelectric sensor converts light into an electrical signal, it is precisely because the absorption of light by the artery changes while the absorption of light by other tissues remains basically unchanged that the obtained signal can be divided into a direct current (DC) signal and an alternating current (AC) signal. By extracting the AC signal and combining it with a certain algorithm, the characteristics of human blood flow can be obtained, so that target parameters such as heart rate, blood pressure, and blood oxygen saturation can be obtained.

PPG technology measures target parameters such as heart rate, blood pressure, and blood oxygen saturation through PPG modules. Currently, PPG modules have been integrated into electronic devices such as smart watches and wristbands to achieve the purpose of continuous monitoring. Among them, how to design and make PPG modules has become an important topic in the industry.

As shown in FIG. 1 , FIG. 1 is a schematic diagram of the structure of a PPG module in the related art. The PPG module in the related art includes a first sub-board 101 , a second sub-board 102 , a light-emitting element 21 , a photoelectric sensor 22 , a barrier portion 3 and a device 23 .

The first sub-board 101 and the second sub-board 102 are stacked and electrically connected through solder joints. The first sub-board 101 is arranged on a side of the second sub-board 102 close to the back cover 220 of the electronic device housing, that is, the first sub-board 101 is located on the upper side of the second sub-board 102 in Figure 1.

The light-emitting element 21 and the photoelectric sensor 22 are arranged on the upper surface of the first sub-board 101 (that is, the side surface close to the back cover 220), and the barrier part 3 is bonded to the upper surface of the first sub-board 101 and the back cover 220 through an adhesive layer. The barrier part 3 is arranged between the light-emitting element 21 and the photoelectric sensor 22 to block light, thereby preventing light from leaking between the light-emitting element 21 and the photoelectric sensor 22.

The device 23 is arranged on the lower surface of the second sub-board 102 (that is, the side surface of the second sub-board 102 facing away from the back cover 220), wherein the device 23 includes a chip 231, a protective cover 232, a passive device 233, a magnetic component 234 (such as a magnet), and an elevated board 235 (for connecting a flexible circuit board), etc.

This PPG module in the related art will occupy a certain area because the barrier part 3 is set on the first sub-board 101, which will squeeze the layout space of other devices 23, making the area utilization rate of the side surface of the first sub-board 101 close to the back cover 220 low, thereby limiting the number of devices 23 that can be arranged in the PPG module.

In order to solve the above technical problems, the present application provides a PPG module and a manufacturing method thereof, and an electronic device. By embedding some devices on the circuit board 1 into the interior of the barrier part 3, the area utilization rate of the first surface (the side surface close to the back cover) of the circuit board 1 is improved.

The electronic device in the embodiment of the present application can be an electronic device with a PPG module, such as a smart watch and a smart bracelet. The following takes a smart watch as an example to specifically introduce the structure of the electronic device in the embodiment of the present application and its internal PPG module. Other electronic devices can be specifically set with reference to the structure of the PPG module in the embodiment of the smart watch, which will not be repeated here.

As shown in FIG. 2 , FIG. 2 is a schematic diagram of the structure of a smart watch in some embodiments of the present application. The smart watch includes a housing 200, a wrist band 300 connected to the housing 200, and a PPG module 100, a battery assembly 410, a circuit board 420 (also referred to as a main board), and a display panel 430 disposed in the housing 200. Along the thickness direction Z of the housing 200, the PPG module 100 and the circuit board 420 are respectively disposed on opposite sides of the battery assembly 410, and the display panel 430 is disposed on a side of the circuit board 420 away from the battery assembly 410.

The display panel 430 is used to display images, videos, etc. The display panel 430 may be a liquid crystal display (LCD) display panel, an organic light emitting diode (OLED) display panel, a flexible light emitting diode (FLED) display panel, a quantum dot light emitting diode (QLED) display panel, etc., which are not specifically limited here.

In some embodiments, as shown in FIG. 2 , the housing 200 is in the shape of a circular frame, and a matching structure (not shown in the figure) for installing the wrist strap 300 is provided on the side of the housing 200. The wrist strap 300 can be reliably connected with the housing 200 through the matching structure on the side wall of the housing 200, so that the smart watch can be reliably worn on the user's hand. Of course, the housing 200 is not limited to being in the shape of a circular frame. In other embodiments, the housing 200 is roughly in the shape of a rectangular frame, and the four corners of the housing 200 are provided with rounded corners, so that the smart watch has better appearance characteristics.

In some embodiments, the wrist band 300 is detachably connected to the housing 200. This allows the user to easily replace the wrist band 300. For example, the user can purchase multiple styles of wrist bands 300 and replace the wrist band 300 according to the usage scenario to improve the convenience of use. For example, the user can use a more formal wrist band 300 in formal occasions and a casual style wrist band 300 in leisure and entertainment occasions.

In some embodiments, as shown in Figure 2, the shell 200 includes a front shell 210 and a back cover 220, the back cover 220 and the front shell 210 are detachably connected, the PPG module 100 is fixedly connected to the back cover 220, and the battery assembly 410, the circuit board 420 and the display panel 430 are fixed in the front shell 210.

When assembling the smart watch, the PPG module 100 and the back cover 220 can be assembled together to form the back cover 220 assembly; the battery assembly 410, the circuit board 420 and the display panel 430 can be assembled together with the front shell 210 to form the front shell 210 assembly; and then the back cover 220 assembly can be assembled with the front shell 210 assembly to complete the assembly of the smart watch. By separating the smart watch into the back cover 220 assembly and the front shell 210 assembly, the disassembly and maintenance of the internal components in the smart watch, such as the PPG module 100 and the battery assembly 410, can be greatly facilitated.

As shown in FIG. 2 , the wrist strap 300 is connected to the side wall of the front shell 210 , but it is not limited thereto. If there is enough space on the side wall of the rear cover 220 , the wrist strap 300 may also be connected to the side wall of the rear cover 220 .

In some embodiments, as shown in FIG. 2 , a motor 440 is further provided in the housing 200, and the motor 440 is disposed between the side wall of the housing 200 (such as the side wall of the front housing 210) and the battery assembly 410. Of course, the position of the motor 440 is not limited to being disposed between the side wall of the housing 200 and the battery assembly 410, and can also be disposed at other locations of the housing 200. In the space, no specific limitation is made here.

Motor 440 is used to generate vibration prompts. Specifically, motor 440 can be used for incoming call vibration prompts, and can also be used for touch vibration feedback. For example, touch operations acting on different applications (such as taking pictures, audio playback, etc.) can correspond to different vibration feedback effects. For touch operations acting on different areas of the display panel 430, motor 440 can also correspond to different vibration feedback effects. Different application scenarios (for example: time reminders, receiving information, alarm clocks, games, etc.) can also correspond to different vibration feedback effects.

As shown in FIG3 , FIG3 is a schematic diagram of the connection between the PPG module 100 and the back cover 220 in the first embodiment of the present application, and FIG3 is a B-B cross-sectional view of FIG6 when the barrier 3 and the back cover 220 are provided. The PPG module 100 includes a circuit board 1, and a light emitting element 21, a photoelectric sensor 22, a first device 4, and a barrier 3 provided on a first surface 11 of the circuit board 1 (the upper surface of the circuit board 1 shown in the figure).

As shown in FIG3 , the light-emitting element 21 may be an LED (Light-Emitting Diode). Specifically, the light-emitting element 21 may be one of a red LED, an infrared LED, a blue LED, and a green LED. The number of the light-emitting elements 21 may be one or more, which is not specifically limited herein.

The photoelectric sensor 22 is a device that converts an optical signal into an electrical signal. The working principle of the photoelectric sensor 22 is that when light irradiates the photoelectric sensor 22 , the photoelectric sensor 22 absorbs the energy of photons and generates photocurrent.

As shown in FIG3 , the photoelectric sensor 22 may be a photodiode (also called a photosensitive diode; English explanation: photodiode; English abbreviation: PD). However, it is not limited thereto, and the photoelectric sensor 22 may also be a phototransistor, etc., depending on the actual situation. The number of the photoelectric sensors 22 may be one or more, which is not specifically limited here.

The barrier 3 is used to block light and at least a portion thereof is located between the light emitting element 21 and the photoelectric sensor 22 to prevent the light emitted by the light emitting element 21 from directly irradiating the photoelectric sensor 22 , thereby preventing light from crossing between the light emitting element 21 and the photoelectric sensor 22 .

Among them, the barrier 3 can be partially located between the light emitting element 21 and the photoelectric sensor 22, for example, as shown in FIG5, FIG5 is an A-A cross-sectional view of FIG3, the barrier 3 covers the first surface 11, and leaves an opening at the position corresponding to the light emitting element 21 and the photoelectric sensor 22. Of course, the barrier 3 can also be completely located between the light emitting element 21 and the photoelectric sensor 22, that is, the barrier 3 forming the periphery of the array of the light emitting element 21 and the photoelectric sensor 22 in FIG5 is removed.

As shown in FIG. 3 , the barrier portion 3 is bonded to the rear cover 220 , but the present invention is not limited thereto. The barrier portion 3 and the rear cover 220 may also be connected together by snapping, plugging, or the like.

The back cover 220 is provided with light windows at positions corresponding to the light emitting element 21 and the photoelectric sensor 22. The back cover 220 can be partially transparent at the light windows, and the light windows can allow light to pass through. Of course, it is not limited to this, and the back cover 220 can also be transparent as a whole. With such a design, the light emitted by the light emitting element 21 can be emitted outside the housing 200 through the light windows, and the light outside the housing 200 can be emitted to the photoelectric sensor 22 through the light windows.

The first device 4 is embedded in the interior of the barrier 3. As shown in FIG3 , the first device 4 can be completely embedded in the interior of the barrier 3. However, it is not limited thereto, and the first device 4 can also be partially embedded in the interior of the barrier 3, which can be determined according to actual conditions.

As shown in Figure 3, the PPG module 100 also includes an elevated board 6 arranged on the second surface 12 of the circuit board 1, and the elevated board 6 is welded together with the circuit board 1, wherein the second surface 12 (that is, the lower surface of the circuit board 1 in the figure) is arranged opposite to the first surface 11.

The elevated board 6 is electrically connected to the battery assembly 410 and the circuit board 420 through the flexible circuit board 420 (not shown in the figure), thereby realizing the electrical connection between the PPG module 100 and the battery assembly 410 and the circuit board 420. Of course, the elevated board 6 may not be provided according to actual conditions, and the second surface 12 of the circuit board 1 may be directly electrically connected to the battery assembly 410 and the circuit board 420 through the flexible circuit board 420.

The PPG module 100 in the embodiment of the present application embeds the first device 4 into the interior of the barrier portion 3, so that the first device 4 can fully utilize the area covered by the barrier portion 3 on the first surface 11 of the circuit board 1, thereby facilitating the improvement of the area utilization rate of the first surface 11 of the circuit board 1, so that more area can be freed up on the circuit board 1 to arrange more devices, thereby increasing the number of devices that can be arranged in the PPG module 100.

The type of the first device 4 is not unique. In some embodiments, as shown in FIG3 , the first device 4 includes a first chip 41. Since the first chip 41 is usually designed in a sheet shape, the first chip 41 occupies a relatively large area on the circuit board 1 compared to a columnar device. By embedding the first chip 41 inside the barrier 3, the area of the first surface 11 covered by the barrier 3 can be maximized. At the same time, the first chip 41 is embedded inside the barrier 3, which can reduce the number of other types of chips arranged on the second surface 12 of the circuit board 1, so that more space can be freed up on the second surface 12 of the circuit board 1 to arrange more devices.

The first chip 41 included in the first device 4 may be one of a wireless charging chip, a capacitive sensor, an accelerometer, an analog front-end processing chip, an operational amplifier, an ADC converter, and an analog switch.

As shown in FIG. 4 , FIG. 4 is a block diagram of the structure of the PPG module 100 in some embodiments of the present application. The analog front-end processing chip (Analog Front End, AFE for short) includes a first terminal L1, a second terminal L2, a third terminal L3 and a fourth terminal L4. The first terminal L1 is connected to the light-emitting element 21, the second terminal L2 is connected to the main control unit (Micro Control Unit, MCU for short), the third terminal L3 is connected to the photoelectric sensor 22, and the fourth terminal L4 is connected to the operational amplifier through an analog switch. An ADC converter is connected between the operational amplifier and the main control unit. The main control unit is arranged on a circuit board 420.

In some embodiments, as shown in FIG4 , the analog front-end processing chip is used to drive the light-emitting element 21 to emit light, and convert the photocurrent signal emitted by the photoelectric sensor 22 into a voltage signal. The analog front-end processing chip includes a driver, a transimpedance amplifier (Trans-Impedance Amplifier, TIA for short) and a filter. The driver is connected between the first terminal L1 and the second terminal L2, and the trans-group amplifier and the filter are connected between the third terminal L3 and the fourth terminal L4. The driver is used to drive the light-emitting element 21 to emit light, the transimpedance amplifier is used to convert the photocurrent signal emitted by the photoelectric sensor 22 into a voltage signal, and the filter is used to filter out the noise in the above voltage signal.

The analog switch is used to switch and connect the two lines between the filter and the operational amplifier. The operational amplifier is used to amplify the voltage signal output by the analog front-end processing chip. The ADC converter is used to convert the analog signal output by the operational amplifier into a digital signal; the main control unit obtains the target detection parameters according to the input digital signal.

The accelerometer is connected to the main control unit and is used to detect the motion state of the user wearing the smart watch and the posture of the smart watch. The capacitive sensor is connected to the main control unit and is used to detect whether the smart watch is worn. The wireless charging chip is connected to the main control unit and the battery assembly 410. The wireless charging chip is used to charge the battery assembly 410. The main control unit can control the charging state of the wireless charging chip. For example, after the battery assembly 410 is fully charged, the main control unit can cut off the connection between the battery assembly 410 and the wireless charging chip to stop charging.

In some embodiments, as shown in FIG. 5 and FIG. 6 , FIG. 6 is a diagram of FIG. 3 after removing the back cover 220 and the barrier 3 The first device 4 includes a plurality of first chips 41, and a portion of the first chips 41 are bare chips (DIE for short).

For example, as shown in FIG6 , the first device 4 includes three first chips 41 , namely a first chip 41 a , a first chip 41 b , and a first chip 41 c , wherein the first chip 41 b and the first chip 41 c are bare chips.

Of course, each first chip 41 embedded in the barrier portion 3 may also be configured as a bare chip, that is, the first chip 41a, the first chip 41b, and the first chip 41c in FIG. 6 are all bare chips.

By setting at least a portion of the first chips 41 embedded in the barrier portion 3 as bare chips, the barrier portion 3 can protect the bare chips, and the bare chips do not need to be packaged, which is beneficial to reducing costs.

In some embodiments, as shown in FIG3 and FIG6 , at least one of the multiple first chips 41 included in the first device 4 is an analog front-end processing chip, that is, the analog front-end processing chip is arranged on the first surface 11 and embedded in the interior of the barrier 3. Compared with arranging the analog front-end processing chip on the second surface 12, arranging the analog front-end processing chip on the first surface 11 and embedded in the interior of the barrier 3 can make the analog front-end processing chip and the light-emitting element 21 and the photoelectric sensor 22 all arranged on the same surface of the circuit board 1, so that the path length of the electrical connection between the analog front-end processing chip and the light-emitting element 21 and the photoelectric sensor 22 can be shortened, thereby making the connection between the analog front-end processing chip and the light-emitting element 21 and the photoelectric sensor 22 more convenient and saving the length of the line.

For example, as shown in FIG6 , the first device 4 includes three first chips 41, namely, a first chip 41a, a first chip 41b, and a first chip 41c, wherein the first chip 41a is an analog front-end processing chip. Of course, two of the first chips 41a, 41b, and 41c may be analog front-end processing chips, for example, the first chip 41a and the first chip 41b are both analog front-end processing chips, and the number of analog front-end processing chips may be set according to the actual solution.

In some embodiments, as shown in FIG6 , the first chip 41 is disposed at the edge region of the first surface 11. In this way, the occupation of the central region of the first surface 11 by the first chip 41 can be reduced, and the probability of positional interference between the first chip 41 and the light emitting element 21 or the photoelectric sensor 22 in the central region of the first surface 11 is reduced, thereby facilitating the optimized layout of the light emitting element 21 and the photoelectric sensor 22.

Among them, the light-emitting element 21 and the photoelectric sensor 22 can adopt the following layout, as shown in Figure 6, the number of photoelectric sensors 22 and the number of light-emitting elements 21 are both multiple, and the multiple light-emitting elements 21 and the multiple photoelectric sensors 22 are alternately arranged along the circumference of the circuit board 1 to form a first array, and a photoelectric sensor 22 is provided on the inner side of the first array.

For example, as shown in Figure 6, the photoelectric sensor 22 is a photodiode, the number of the photoelectric sensors 22 is four, namely PD1, PD2, PD3 and PD4, the light-emitting element 21 is an LED, the number of the light-emitting element 21 is three, namely LED1, LED2 and LED3, PD1 is arranged at the center of the first surface 11, PD2, PD3, PD4, and LED1, LED2 and LED3 are alternately arranged around PD1 to form a first array, specifically, two adjacent ones of PD2, PD3, PD4 are separated by 120° in the circumferential direction of the circuit board 1, and two adjacent ones of LED1, LED2, LED3 are also separated by 120° in the circumferential direction of the circuit board 1, and LED1 is arranged between PD2 and PD3, LED2 is arranged between PD3 and PD4, and LED3 is arranged between PD2 and PD4.

In some embodiments, as shown in FIG3 and FIG6 , the first device 4 includes a first passive device 42, and the first passive device 42 includes at least one of an inductor, a resistor, and a capacitor. Since the number of the first passive devices 42 in the circuit of the PPG module 100 is relatively large, by embedding a large number of the first passive devices 42 in the barrier 3, the number of other passive devices arranged on the second surface 12 of the circuit board 1 can be reduced, so that the second surface 12 of the circuit board 1 can free up more space to arrange more devices.

In some embodiments, as shown in FIG6 , the first passive device 42 is disposed at the edge region of the first surface 11. In this way, the occupation of the central region of the first surface 11 by the first passive device 42 can be reduced, and the probability of positional interference between the first passive device 42 and the light emitting element 21 or the photoelectric sensor 22 in the central region of the first surface 11 is reduced, thereby facilitating the optimized layout of the light emitting element 21 and the photoelectric sensor 22.

In some embodiments, as shown in FIG. 3 and FIG. 6 , the first device 4 includes a magnetic member 43 that can generate magnetic attraction, such as a magnet. The magnetic member 43 can be attracted to the charging base of the smart watch to charge and position the smart watch. Since the magnetic member 43 is arranged on the first surface 11 and embedded in the barrier 3, the magnetic member 43 is closer to the back cover 220, and then the magnetic member 43 is closer to the charging base, thereby ensuring the effect of magnetic attraction between the magnetic member 43 and the smart watch.

In some embodiments, as shown in FIG6 , the magnetic member 43 is disposed in the central area of the first surface 11. With such a design, the magnetic force received by the smart watch during charging acts on the central area of the smart watch, making it easier for the smart watch to maintain balance and less prone to deflection.

In some embodiments, as shown in FIG6 , a plurality of magnetic members 43 (four in the figure) are provided in the first array, and the plurality of magnetic members 43 are arranged around the photoelectric sensor 22 (that is, PD1 in the figure) located inside the first array. With such a design, not only can the magnetic member 43 more fully utilize the gap between the photoelectric sensor 22 located inside the first array and the first array, and not easily interfere with the photoelectric sensor 22 and the light-emitting element 21, but also the magnetic force received by the smart watch during wireless charging is more uniform, so that the smart watch is easier to keep balanced.

It should be noted that the first device 4 can include the first chip 41, the first passive device 42 and the magnetic component 43 (as shown in FIG6 ). In this way, the first device 4 is embedded in the interior of the barrier 3, so that the circuit board 1 can free up more area for device layout, so that the effective layout area of the circuit board 1 is greater than 200 mm ² . Of course, the first device 4 can also include only one of the first chip 41, the first passive device 42 and the magnetic component 43, or any two of the first chip 41, the first passive device 42 and the magnetic component 43, which is not specifically limited here.

In some embodiments, as shown in FIG3 , the height of the first device 4 is less than the height of the barrier 3. With such a design, the first device 4 can be completely embedded in the barrier 3, thereby preventing the first device 4 from extending out of the upper surface of the barrier 3 (the side surface close to the back cover 220) and causing the thickness of the PPG module 100 to increase.

In some embodiments, as shown in FIG3 , the material of the barrier portion 3 is epoxy molding compound. Since the thermal conductivity of the epoxy molding compound (about 0.97 W/m·K) is greater than the thermal conductivity of air (0.023-0.26 W/m·K), the heat dissipation effect of embedding the first device 4 in the barrier portion 3 is better than that of air, so that the temperature of the first device 4 can be effectively controlled from being too high.

As shown in Figures 7 and 8, Figure 7 is a schematic diagram of the connection between the PPG module 100 and the back cover 220 in the second embodiment of the present application, Figure 7 is a C-C cross-sectional view of Figure 8 when the barrier 3 and the back cover 220 are set, and Figure 8 is a top view of Figure 7 after the back cover 220 and the barrier 3 are removed. The main difference between the structure of the PPG module 100 in the second embodiment and the structure of the PPG module 100 in the first embodiment is that in addition to the elevated plate 6, the second surface 12 of the circuit board 1 is also provided with some devices, such as the second chip 71, and the second chip 71 can be one of a wireless charging chip, a capacitive sensor, an accelerometer, an analog front-end processing chip, an operational amplifier, an ADC converter, and an analog switch. When the second chip 71 is a wireless charging chip, the second chip 71 is encapsulated by an encapsulation layer 72, and the material of the encapsulation layer 72 can be an epoxy molding compound to ensure the heat dissipation of the wireless charging chip (the second chip 71) and not being interfered by surrounding devices.

As for the arrangement of the barrier 3, the first device 4, the light emitting element 21, and the photoelectric sensor 22 in the second embodiment, For details, please refer to the settings in the first embodiment, which will not be described in detail here.

As shown in Fig. 9A and Fig. 9B, Fig. 9A is a schematic diagram of the connection between the PPG module 100 and the back cover 220 in the third embodiment of the present application, Fig. 9A is a D-D cross-sectional view of Fig. 9B when the baffle 3 and the back cover 220 are provided, and Fig. 9B is a top view of Fig. 9A after the back cover 220 and the baffle 3 are removed. The main difference in structure between the PPG module 100 in the third embodiment and the PPG module 100 in the first embodiment is that the PPG module 100 in the third embodiment further includes a second device 5, the height of the second device 5 is less than the thickness of the circuit board 1, and the second device 5 is embedded in the inside of the circuit board 1.

By making the height of the second device 5 smaller than the thickness of the circuit board 1, the second device 5 can be completely embedded in the interior of the circuit board 1, which not only avoids the increase in the thickness of the PPG module 100 caused by the second device 5 extending out of the surface of the circuit board 1 (such as the second surface 12), but also makes full use of the space inside the circuit board 1, thereby reducing the surface space occupied by the second device 5 on the circuit board 1. In this way, more area on the surface of the circuit board 1 can be freed up (for example, the second surface 12 of the circuit board 1 can be completely freed up) to arrange more devices.

In addition, if the first surface 11 of the circuit board 1 and the interior of the circuit board 1 are sufficient to arrange the devices of the PPG module 100, then, as shown in Figure 9A, the second surface 12 of the circuit board 1 may not need to be arranged with devices. This can avoid the devices arranged on the second surface 12 of the circuit board 1 increasing the thickness of the PPG module 100, thereby helping to reduce the thickness of the PPG module 100.

In some embodiments, as shown in FIG9A , the second device 5 is an analog front-end processing chip, that is, the analog front-end processing chip is embedded in the circuit board 1. Compared with setting the analog front-end processing chip on the second surface 12, embedding the analog front-end processing chip in the circuit board 1 makes the distance between the analog front-end processing chip and the first surface 11 closer, thereby shortening the path length of the electrical connection between the analog front-end processing chip and the light-emitting element 21 and the photoelectric sensor 22, thereby facilitating the electrical connection between the analog front-end processing chip and the light-emitting element 21 and the photoelectric sensor 22, and saving the length of the line.

Among them, one analog front-end processing chip can be embedded in the inside of the circuit board 1, or multiple analog front-end processing chips (two analog front-end processing chips shown in Figure 9A) can be embedded in the inside of the circuit board 1, depending on the actual situation.

In some embodiments, as shown in FIG9A , the second device 5 and the first device 4 are disposed on the same circuit board 1. Compared with disposing the second device 5 and the first device 4 on two stacked circuit boards 1 respectively, disposing the second device 5 and the first device 4 on the same circuit board 1 can make the structure of the circuit board 1 more compact, and eliminate the solder joint structure between the two stacked circuit boards 1, thereby facilitating the reduction of the thickness of the PPG module 100.

As for the arrangement of the barrier 3, the first device 4, the light emitting element 21, and the photoelectric sensor 22 in the third embodiment, specific reference may be made to the arrangement in the first embodiment, and no further details will be given here.

In order to better illustrate that the thickness of the PPG module 100 in the embodiment of the present application is relatively thin, the thickness of the PPG module 100 in the second embodiment and the third embodiment of the present application is compared with the thickness of the PPG module in the related art:

As shown in FIG1 , the dimension h1=0.58 mm from the top of the barrier portion 3 to the bottom of the first sub-board 101, the thickness of the second sub-board h2=0.6 mm, the height of the protective cover 232 h3=0.4 mm, and since the solder joint between the first sub-board 101 and the second sub-board 102 also has a certain height, the thickness of the entire PPG module is greater than 1.58 mm.

As shown in FIG7 , the height H1 of the baffle 3 is 0.4 mm, the thickness H2 of the circuit board 1 is 0.4 mm, and the height H3 of the elevated board 6 is 0.6 mm. The thickness of the PPG module 100 in the second embodiment of the present application is 1.4 mm, which is The thickness of the PPG module in this technology has been reduced by at least 0.18mm.

As shown in FIG9A , the height H1 of the barrier 3 is 0.4 mm, the thickness H2 of the circuit board 1 is 0.4 mm, and when the second surface 12 of the circuit board 1 is connected to the flexible circuit board, the height of the solder joints set on the second surface 12 is 0.2 mm. The thickness of the PPG module 100 in the third embodiment of the present application is 1 mm, which is at least 0.58 mm thinner than the thickness of the PPG module in the related art. When the height of the solder joints is not calculated, the thickness of the PPG module 100 in the third embodiment of the present application is 0.8 mm, which is less than 1 mm.

As shown in FIG. 10 and FIG. 11A to FIG. 11G, FIG. 10 is a manufacturing flow chart of the PPG module 100 in some embodiments of the present application, and FIG. 11A to FIG. 11G are schematic diagrams of the manufacturing process of the PPG module 100 in some embodiments of the present application. The manufacturing method of the PPG module 100 includes:

S1. As shown in FIG. 11A and FIG. 11B , a first device 4 is disposed on a first surface 11 of a wiring board 1 (the upper surface of the wiring board 1 shown in the figures).

As shown in FIG11A , the first surface 11 of the circuit board 1 is provided with a solder pad at a corresponding position, and as shown in FIG11B , the first device 4 can be electrically connected to the solder pad on the first surface 11 through a surface mounting process (surface mounted technology, SMT for short).

S2. As shown in FIG. 11C and FIG. 11D , a blocking portion 3 for blocking light is provided on the first surface 11 so that the first device 4 is embedded in the inside of the blocking portion 3 , and at least a portion of the blocking portion 3 is located between the first area 111 and the second area 112 of the first surface 11 .

The first area 111 and the second area 112 are areas reserved on the circuit board 1 for the light emitting element 21 and the photoelectric sensor 22 .

S3. As shown in FIG. 11E , the light emitting element 21 is disposed in the first region 111 , and the photoelectric sensor 22 is disposed in the second region 112 .

As shown in FIG11E , the light-emitting element 21 may be first bonded to the first region 111 and then electrically connected to the pad on the first surface 11 by wire bonding; similarly, the photoelectric sensor 22 may be first bonded to the second region 112 and then electrically connected to the pad on the first surface 11 by wire bonding.

In addition to electrically connecting the light emitting element 21 and the photoelectric sensor 22 to the circuit board 1 in the above manner, the light emitting element 21 and the photoelectric sensor 22 may also be electrically connected to the pads on the first surface 11 by surface mounting technology.

In some embodiments, after S3 , the process further includes: S4 , as shown in FIG. 11F , disposing devices such as a raised board 6 and a second chip 71 on the second surface 12 of the circuit board 1 to fully utilize the space on the circuit board 1 .

In some embodiments, after S4, the process further includes: S5, as shown in FIG11G , bonding the barrier 3 to the back cover 220. In this way, the PPG module 100 and the back cover 220 form a back cover 220 assembly, so as to be combined with the front shell 210 assembly to form a smart watch.

The manufacturing method of the PPG module 100 in the embodiment of the present application is to set a barrier portion 3 on the first surface 11 so that the first device 4 is embedded in the barrier portion 3, so that the first device 4 can fully utilize the area covered by the barrier portion 3 on the first surface 11 of the circuit board 1, thereby facilitating the improvement of the area utilization rate of the first surface 11 of the circuit board 1, so that more space can be freed up on the second surface 12 of the circuit board 1 to arrange more devices, thereby increasing the number of devices that can be arranged in the PPG module 100. In this way, the devices in the PPG module 100 can be arranged on the same circuit board 1. Since the structure of a circuit board 1 is relatively compact, the solder joints for soldering multiple sub-boards together are omitted, so that the thickness of the entire PPG module 100 can be reduced, which is beneficial to the PPG module 100. Lightness and thinness.

There is no unique way to embed the first device 4 into the interior of the barrier portion 3 in S2. In some embodiments, the barrier portion 3 can be formed by a mold so that the first device 4 is embedded into the interior of the barrier portion 3. Specifically, a barrier portion 3 for blocking light is provided on the first surface 11 so that the first device 4 is embedded into the interior of the barrier portion 3, including:

S21 , as shown in FIG. 11C , placing the circuit board 1 in the mold cavity of the lower mold 510 .

S22 , as shown in FIG. 11C , the upper mold 520 and the lower mold 510 are molded together to form a receiving cavity 521 for receiving the first device 4 between the upper mold 520 and the circuit board 1 .

As shown in FIG11C , an injection channel 522 and an exhaust channel 523 are provided on the upper mold 520. The injection channel 522 allows the material to be injected into the accommodating cavity 521. The exhaust channel 523 is used to exhaust the gas in the accommodating cavity 521. The number of the accommodating cavities 521 corresponds to the number of the first devices 4, and the multiple accommodating cavities 521 are interconnected, so that the subsequent light-shielding material can fill the multiple accommodating cavities 521.

S23, injecting a light shielding material into the accommodating cavity 521 to cover the first device 4, and demoulding the light shielding material after it is cooled to form a barrier portion 3 (as shown in FIG11D ).

The barrier portion 3 is formed by a mold so that the first device 4 is embedded in the barrier portion 3. Thus, the barrier portion 3 can be made into various shapes by adjusting the shape of the cavity of the upper mold 520 to meet the requirements of embedding the first device 4 of different shapes. At the same time, after the barrier portion 3 is formed, there is no need to perform extensive processing on the barrier portion 3, which reduces the damage to the circuit board 1 caused by subsequent processing.

In some embodiments, after placing the circuit board 1 in the mold cavity of the lower mold 510 and before closing the upper mold 520 with the lower mold 510, as shown in FIG11C, it further includes: covering the first area 111 and the second area 112 with a protective layer 530 for contacting the upper mold 520. In this way, it is possible to avoid direct contact between the upper mold 520 and the first area 111 and the second area 112 of the circuit board 1 to damage the circuit board 1, thereby ensuring that the subsequent light-emitting element 21 and the photoelectric sensor 22 can be smoothly installed in the first area 111 and the second area 112.

As shown in FIG. 11C , the protective layer 530 may be an elastic protective pad, such as a rubber pad, a silicone pad, etc. In addition, the protective layer 530 may also be a protective rubber layer.

In addition to being formed by a mold, the barrier portion 3 can also be formed by the following method: a light shielding layer is provided on the first surface 11 of the circuit board 1 to cover the first device 4. A clearance opening is provided at the position of the light shielding layer corresponding to the first area 111 and the second area 112 to form the barrier portion 3. The clearance opening can be formed by laser cutting or by photolithography, which is not specifically limited here.

As shown in Figures 12A to 12K, Figures 12A to 12K are schematic diagrams of the manufacturing process of the PPG module 100 in other embodiments of the present application. The main differences between the manufacturing method of the PPG module 100 shown in Figures 12A to 12K and the manufacturing method of the PPG module 100 shown in Figures 11A to 11G are:

Before the first device 4 is arranged on the first surface 11 of the circuit board 1 , the process further includes: S0 , as shown in FIGS. 12A to 12G , embedding the second device 5 inside the circuit board 1 .

The embedding of the second device 5 inside the circuit board 1 may be achieved in the following manner. In some embodiments, the embedding of the second device 5 inside the circuit board 1 includes:

S01. As shown in FIGS. 12A to 12E , a second device 5 is embedded in the first dielectric layer 13 so that the conductive portion 51 of the second device 5 is exposed from the surface of the first dielectric layer 13 (the upper surface of the first dielectric layer 13 shown in FIG. 12E ).

The first dielectric layer 13 may or may not be provided with a circuit, which is not specifically limited here.

When a circuit is arranged on the first dielectric layer 13, the second device 5 can be embedded in a portion of the first dielectric layer 13 where no circuit is arranged. The process of manufacturing the circuit on the first dielectric layer 13 is as follows.

As shown in FIG12A , a first dielectric layer 13 covered with a conductive layer 14 is provided; wherein the conductive layer 14 may cover two opposite surfaces of the first dielectric layer 13 (i.e., the upper surface and the lower surface of the first dielectric layer 13 in the figure), or may cover one surface of the first dielectric layer 13, which is not specifically limited here; the conductive layer 14 may be a copper layer, or may be other conductive metal layers, which is not specifically limited here.

As shown in FIG12B , the conductive layer 14 covered on the first dielectric layer 13 is made into a circuit; wherein the circuit can be formed by a photolithography process or by laser engraving, which is not specifically limited here. As shown in FIG12B , when the two opposite surfaces of the first dielectric layer 13 have circuits, vias can be provided on the first dielectric layer 13 to electrically connect the circuits on the two opposite surfaces of the first dielectric layer 13.

S02, as shown in FIG. 12F and FIG. 12G, a second dielectric layer 15 is stacked on the first dielectric layer 13 so that the second dielectric layer 15 covers the second device 5, and a circuit electrically connected to the conductive part 51 is made on the second circuit board 1 layer.

Among them, the circuit board 1 includes a first dielectric layer 13 and a second dielectric layer 15. The second dielectric layer 15 and the first dielectric layer 13 can be separately provided, as shown in Figures 12F and 12G, or can be integrally formed. For example, the second dielectric layer 15 can be integrally formed with the first dielectric layer 13 by thermal pressing.

The number of the second dielectric layer 15 can be one layer, as shown in FIG12G , or multiple layers, which is not specifically limited here. When the second dielectric layer 15 is multiple layers (such as two layers), the multiple layers of the second dielectric layer 15 can be integrally formed by thermal compression.

In this embodiment, the second device 5 is embedded into the inside of the circuit board 1 by sequentially arranging a plurality of stacked dielectric layers. Compared with the method of directly embedding by making grooves on the circuit board 1, such embedding method has relatively less impact on the circuit inside the circuit board 1. For example, the embedding of the second device 5 in the first dielectric layer 13 has no impact on the circuit layout on the second dielectric layer 15.

In some embodiments, as shown in FIG. 12F and FIG. 12G , after the second dielectric layer 15 is stacked on the first dielectric layer 13, at least one third dielectric layer 16 (two third dielectric layers 16 are shown in FIG. 12G ) is stacked on the side of the first dielectric layer 13 away from the second dielectric layer 15 to meet the needs of circuit layout. The circuit board 1 also includes the third dielectric layer 16, which can be integrally formed with the first dielectric layer 13 by thermal compression.

In some embodiments, embedding the second device 5 on the first dielectric layer 13 so that the conductive portion 51 of the second device 5 is exposed from the surface of the first dielectric layer 13 includes:

S011 . As shown in FIG. 12C , a receiving groove 131 penetrating through the first dielectric layer 13 is opened on the first dielectric layer 13 .

The receiving grooves 131 may be formed by laser cutting or by cutting with a cutter, which is not specifically limited here. The specific number of the receiving grooves 131 may be equal to the number of the second devices 5. For example, if there are two second devices 5, two receiving grooves 131 need to be opened on the first dielectric layer 13.

S012 , as shown in FIG. 12D , the carrier film 600 bonded with the second device 5 is stacked on the first dielectric layer 13 , so that the second device 5 is located in the receiving groove 131 .

The second device 5 has a side with the conductive part 51 bonded to the carrier film 600 , and the carrier film 600 can be bonded to the first dielectric layer 13 , so that the carrier film 600 and the first dielectric layer 13 are connected together and are not easy to move relative to each other.

S013 , as shown in FIG. 12E , fill the insulating material into the receiving groove 131 from the groove on one side of the receiving groove 131 away from the carrier film 600 .

The insulating material may be the same as the material of the first dielectric layer 13. For example, when the material of the first dielectric layer 13 is resin, the insulating material is also resin. When the resin fills the receiving groove 131, the resin may flow into the receiving groove 131 by hot pressing, and then the resin is thermally hardened by hot pressing at high temperature to achieve filling of the receiving groove 131.

Of course, the insulating material is not limited to resin, and may also be other insulating materials that can be heated and melted, and no specific limitation is made here.

S014 , as shown in FIG. 12E , separate the carrier film 600 from the second device 5 , so that the conductive portion 51 of the second device 5 is exposed from the surface of the first dielectric layer 13 .

In this embodiment, the receiving groove 131 is filled with insulating material, so that the gap between the receiving groove 131 and the second device 5 can be eliminated, thereby preventing the second device 5 from shaking in the receiving groove 131. By stacking the carrier film 600 bonded with the second device 5 on the first dielectric layer 13, and bonding the side of the second device 5 provided with the conductive part 51 to the carrier film 600, after the insulating material is filled into the receiving groove 131, the conductive part 51 of the second device 5 can be located at the notch of the receiving groove 131, so that the conductive part 51 is exposed from the surface of the first dielectric layer 13, so as to facilitate the subsequent electrical connection between the circuit on the second dielectric layer 15 and the conductive part 51.

Of course, the receiving groove 131 does not need to penetrate the first dielectric layer 13 , and the second device 5 does not need to be bonded to the carrier film 600 . The second device 5 can be directly placed in the receiving groove 131 , thereby embedding the second device 5 in the first dielectric layer 13 .

As for the manufacturing process of the PPG module 100 shown in Figures 12H to 12K, the specific description can be made with reference to the corresponding descriptions of Figures 11B to 11G, and will not be repeated here.

The features that are the same or similar to those in the product embodiment of the PPG module in the manufacturing method embodiment of the PPG module can be specifically referred to the description in the product embodiment of the PPG module, and will not be repeated here. In the description of this specification, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

The different line types of section lines in the drawings of the present application are mainly used to distinguish different components and should not be understood as a limitation on the materials of the components.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

A PPG module, characterized in that it includes: a circuit board, and a light-emitting element, a photoelectric sensor, a first device and a blocking portion arranged on a first surface of the circuit board, the blocking portion is used to block light, and at least a portion of the blocking portion is located between the light-emitting element and the photoelectric sensor, and the first device is embedded in the interior of the blocking portion.
The PPG module according to claim 1, characterized in that:

The first component includes at least one of a first chip, a first passive component, and a magnetic member capable of generating magnetic attraction; wherein the first passive component includes at least one of an inductor, a resistor, and a capacitor.
The PPG module according to claim 2, characterized in that:

The first device includes a plurality of first chips, and at least a portion of the first chips are bare chips.
The PPG module according to claim 2 or 3, characterized in that:

The first chip and the first passive component are arranged in an edge area of the first surface.
The PPG module according to any one of claims 2 to 4, characterized in that:

The magnetic member is disposed in a central area of the first surface.
The PPG module according to claim 5, characterized in that:

The number of the photoelectric sensors and the number of the light-emitting elements are both multiple, and the multiple light-emitting elements and the multiple photoelectric sensors are alternately arranged along the circumference of the circuit board to form a first array;

The photoelectric sensor and a plurality of magnetic members are disposed on the inner side of the first array, and the plurality of magnetic members are arranged around the photoelectric sensor located on the inner side of the first array.
The PPG module according to any one of claims 3 to 6, characterized in that:

At least one of the first chips is an analog front-end processing chip, which is electrically connected to the light-emitting element and the photoelectric sensor and is used to drive the light-emitting element to emit light and convert the photocurrent signal emitted by the photoelectric sensor into a voltage signal.
The PPG module according to any one of claims 1 to 7, characterized in that:

The height of the first component is smaller than the height of the barrier portion.
The PPG module according to any one of claims 1 to 8, characterized in that:

The PPG module also includes a second device, the height of which is smaller than the thickness of the circuit board, and the second device is embedded in the interior of the circuit board.
The PPG module according to claim 9, characterized in that:

The second device is an analog front-end processing chip, which is electrically connected to the light-emitting element and the photoelectric sensor and is used to drive the light-emitting element to emit light and convert the photocurrent signal emitted by the photoelectric sensor into a voltage signal.
The PPG module according to claim 9 or 10, characterized in that:

The second device and the first device are arranged on the same circuit board.
The PPG module according to any one of claims 1 to 11, characterized in that:

The material of the barrier part is epoxy molding compound.
An electronic device, characterized in that it comprises a housing and the PPG module according to any one of claims 1 to 12, wherein the PPG module is arranged in the housing.
A method for manufacturing a PPG module, characterized by comprising:

Disposing a first device on a first surface of the circuit board;

A blocking portion for shielding light is provided on the first surface, so that the first device is embedded in the blocking portion, and at least a portion of the blocking portion is located between the first area and the second area of the first surface;

A light emitting element is disposed in the first region, and a photoelectric sensor is disposed in the second region.
The method for manufacturing a PPG module according to claim 14, characterized in that:

A blocking portion for blocking light is arranged on the first surface so that the first device is embedded in the blocking portion, comprising:

Placing the circuit board in the mold cavity of the lower mold;

The upper mold is molded together with the lower mold, so that a receiving cavity for receiving the first device is formed between the upper mold and the circuit board;

A light shielding material is injected into the accommodating cavity to cover the first device, and the light shielding material is demoulded after being cooled to form the barrier portion.
The method for manufacturing a PPG module according to claim 15, characterized in that:

After placing the circuit board in the mold cavity of the lower mold and before closing the upper mold with the lower mold, the method further includes:

The first region and the second region are respectively covered with a protection layer for contacting the upper mold.
The method for manufacturing a PPG module according to any one of claims 14 to 16, characterized in that:

Before arranging the first device on the first surface of the circuit board, the method further includes: embedding a second device inside the circuit board; wherein the height of the second device is less than the thickness of the circuit board.
The method for manufacturing a PPG module according to claim 17, characterized in that:

Embedding a second device inside the circuit board includes:

embedding the second device on the first dielectric layer so that the conductive portion of the second device is exposed from the surface of the first dielectric layer;

A second dielectric layer is stacked on the first dielectric layer so that the second dielectric layer covers the second device, and a circuit electrically connected to the conductive part is made on the second dielectric layer; wherein the circuit board includes the first dielectric layer and the second dielectric layer.
The method for manufacturing a PPG module according to claim 18, characterized in that:

Embedding the second device on the first dielectric layer so that the conductive portion of the second device is exposed from the surface of the first dielectric layer includes:

A receiving groove is provided on the first dielectric layer and penetrates the first dielectric layer;

The carrier film bonded with the second device is stacked on the first dielectric layer so that the second device is located in the receiving groove; wherein the side of the second device provided with the conductive part is bonded to the carrier film;

Filling the insulating material into the receiving groove from a notch on one side of the receiving groove away from the carrier film;

The carrier film is separated from the second device so that the conductive portion of the second device is exposed from the surface of the first dielectric layer.