NPO light engine

Abstract

The invention provides an NPO light engine, and belongs to the technical field of photoelectric integrated devices. The NPO light engine includes: an electrical interface connector; a micro-control circuit; the optical transceiving assembly comprises an optical transmitting array, an optical receiving array and an optical fiber array assembly connected with the optical transmitting array and the optical receiving array respectively; the metal heat sink comprises a transmitting end metal heat sink on which a light transmitting array is placed and a receiving end metal heat sink on which a light receiving array is placed; a transmitting end metal heat sink and a receiving end metal heat sink are arranged on the upper surface of the PCB, and a micro-control circuit and an electrical interface connector are arranged on the lower surface of the PCB. Devices on the NPO light engine are compact in layout, and the laser light source of the light emitting array is arranged in the NPO light engine, so that the NPO light engine has the advantages of being high in bandwidth density, high in integration degree, small in size, convenient to use, high in heat dissipation efficiency, low in cost and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic integrated devices, and in particular to a NPO light engine. Background Art

[0002] From the perspective of the common external electrical interface forms of optical modules, there are mainly pluggable gold fingers, LGA spring pin connectors, FPC soft boards, etc.

[0003] Pluggable optical modules are the mainstream form at present. Their electrical interface is a gold finger pad, which can be used by plugging into the connector. This type of optical engine usually designs the loading slot of the optical component into a through-slot structure, that is, the PCB board is dug through in the thickness direction, and the metal heat sink is extended to the bottom of the PCB board to make a larger heat dissipation structure for heat dissipation, and the optical transceiver component is placed on it. However, the wiring space left in the width direction after the groove is dug is too small, and the number of stacked PCB boards needs to be increased.

[0004] The gold finger pads are usually long, with large spacing, and the board thickness is fixed. For example, the OSFP standard pad spacing is 0.65mm, and the board thickness is 1.0mm, which makes the optical engine size usually large, which is not conducive to the miniaturization of the optical engine. The size of the docking board connector is usually large, which increases the transmission distance of the receiving and sending signals, resulting in increased attenuation of high-speed receiving and sending signals. The long-distance transmission path also leads to increased power consumption.

[0005] The LGA spring pin connector is connected to the LGA pad through the deformation of the spring pin, which is a crimping connection method. At the same time, the LGA pad at the bottom of such an optical module almost covers the entire lower surface of the PCB board, and the components can only be arranged on the upper surface of the PCB board, with little layout space. Since the PCB board cannot be dug through in the thickness direction, the loading slot of the optical component of such an optical engine can only be designed as a blind slot structure, with a metal heat sink placed above the blind slot and the optical component placed above the metal heat sink.

[0006] Since the relative placement height of each device in the optical transceiver assembly is strictly required, there is less space left for the metal heat sink, and the heat is more concentrated in a single-sided layout. For small-sized optical engines, this interface method usually only allows the laser light source with higher heat in the optical transceiver assembly to be externalized. Currently, CPO (Co-package optics) optoelectronic co-packaging technology uses this LGA pin interface. CPO technology has the advantages of low power consumption, high performance, high quality, and high transmission.

[0007] In addition, the FPC soft board interface generally needs to be welded by hot pressing, using a fixture to weld one by one, which is not conducive to mass production. The spacing between FPC pads is generally more than 0.5mm. Summary of the invention

[0008] The purpose of the present invention is to at least partially solve the above-mentioned technical problems, and aims to provide a NPO light engine, wherein the device layout on the NPO light engine is compact, and the laser light source of the NPO light engine is built-in. Therefore, the NPO light engine has the characteristics of high bandwidth density, high integration, small size, easy use, high heat dissipation efficiency, low cost, etc.

[0009] In one aspect of the present invention, there is provided a NPO light engine, the NPO light engine comprising:

[0010] Electrical interface connector;

[0011] Microcontroller circuits;

[0012] An optical transceiver assembly, the optical transceiver assembly comprising an optical transmitting array, an optical receiving array and optical fiber array assemblies respectively connected thereto;

[0013] A metal heat sink, wherein the metal heat sink comprises a transmitting end metal heat sink on which a light transmitting array is placed and a receiving end metal heat sink on which a light receiving array is placed;

[0014] A PCB board, wherein a transmitting end metal heat sink and a receiving end metal heat sink are arranged on the upper surface of the PCB board, and a microcontroller circuit and an electrical interface connector are arranged on the lower surface of the PCB board.

[0015] In some embodiments of the present invention, the upper surface of the PCB board is provided with a blind groove for accommodating a metal heat sink, and the metal heat sink is provided with a plurality of loading steps of different heights, and each loading step is placed on each device of the optical transmitting and receiving assembly.

[0016] In some embodiments of the present invention, the blind slot includes a transmitting end loading slot and a receiving end loading slot disposed on the upper surface of the PCB board for accommodating the transmitting end metal heat sink and the receiving end metal heat sink, respectively;

[0017] Edge copper leakage is arranged at the edge of the upper surface of the PCB board, and bottom copper leakage is arranged at the bottom of the transmitting end loading slot and the receiving end loading slot.

[0018] In some embodiments of the present invention, a light emitting end metal heat sink and a light emitting component located on the light emitting end metal heat sink are disposed in the light emitting end loading slot;

[0019] A receiving end metal heat sink and a light receiving component located on the receiving end metal heat sink are arranged in the receiving end loading slot.

[0020] In some embodiments of the present invention, the transmitting-end metal heat sink and the receiving-end metal heat sink are respectively provided with a transmitting-end heat conduction step and a receiving-end heat conduction step;

[0021] In addition to the emitting end heat conduction step, the emitting end metal heat sink also includes a laser light source loading step, a silicon-based modulator loading step and a driver loading step arranged in sequence at different heights;

[0022] In addition to the receiving end heat conduction step, the receiving end metal heat sink also includes a detector loading step and a transimpedance amplifier loading step.

[0023] In some embodiments of the present invention, the light emitting assembly includes: a laser light source, a silicon-based modulator, and a driver, which are respectively located on the laser light source loading step, the silicon-based modulator loading step, and the driver loading step;

[0024] The laser light source comprises: a laser, a first lens, an optical isolator and a second lens which are sequentially arranged on the upper surface of a PCB board and are respectively located on a laser loading step, a first lens loading step, an optical isolator loading step and a second lens loading step of different heights.

[0025] In some embodiments of the present invention, one end of the driver is connected to the silicon-based modulator through a gold wire, the other end of the driver is bonded to a wire bonding pad on a PCB board through a gold wire, and the silicon-based modulator is connected to a laser light source.

[0026] The microcontrol circuit is also connected to the silicon-based modulator, the driver, the transimpedance amplifier, the laser and the female connector respectively;

[0027] One end of the laser is bonded to a wire bonding pad of a PCB board through a gold wire.

[0028] In some embodiments of the present invention, the light receiving component includes a detector and a transimpedance amplifier, which are respectively arranged on the detector loading step and the transimpedance amplifier loading step. One end of the transimpedance amplifier is connected to the detector gold wire, and the other end is bonded to the wire bonding pad on the PCB board through the gold wire.

[0029] In some embodiments of the present invention, the gold wires between the driver and the silicon-based modulator, the gold wires between the driver and the PCB board, the gold wires between the transimpedance amplifier and the detector, and the gold wires between the transimpedance amplifier and the PCB board are configured for high-speed signal transmission and reception.

[0030] In some embodiments of the present invention, the upper surface of the driver is flush with the upper surface of the silicon-based modulator, and the upper surface of the detector is flush with the upper surface of the transimpedance amplifier.

[0031] In some embodiments of the present invention, the NPO light engine further comprises a metal housing;

[0032] The heat conduction steps of the transmitting end metal heat sink and the receiving end metal heat sink extend upward from the blind groove of the PCB board to the upper surface of the PCB board, the bottom surface of the heat conduction step is bonded to the upper surface of the PCB board, the PCB board at the bonding position is provided with an upper surface copper leak, and a heat conduction gel is placed on the top of the heat conduction step, the heat conduction gel is connected to the inner side of the metal shell, and the heat is dissipated from the top of the metal shell of the NPO light engine through the metal shell;

[0033] At least one of the edge copper leakage, the upper surface copper leakage and the bottom surface copper leakage is provided with a thermal conductive via hole, and the thermal conductive via hole is formed by a copper paste plugging process.

[0034] In some embodiments of the present invention, the PCB board has a 6-layer stacked structure.

[0035] The PCB board adopts a first-order HDI drilling method to form a blind groove;

[0036] The via holes in the area below the blind slot are processed by back drilling process;

[0037] The high-speed signal line is the first layer of the 6-layer stacked structure from the top;

[0038] The reference layer is the second layer from the top of the 6-layer stacked structure;

[0039] The low-speed signal lines are the third to sixth layers from the top of the six-layer stacked structure.

[0040] In some embodiments of the present invention, the electrical interface connector includes a male connector for connecting high-speed transceiver signals and a female connector for connecting power and control and debugging signals, and the male connector and the female connector are arranged side by side on both sides of one end of the lower surface of the PCB board;

[0041] The micro-control circuit is located between the male connector and the female connector.

[0042] In some embodiments of the present invention, the male connector pair of the NPO light engine is plugged into the female connector of the host end, and the female connector pair of the NPO light engine is plugged into the male connector of the host end; or

[0043] The male connector and the female connector of the NPO light engine are connected to one end of the FPC soft board through a transfer connection.

[0044] In some embodiments of the present invention, the PCB board is fixedly connected to the metal housing through screw holes;

[0045] wherein the optical fiber array assembly extends through a notch in the metal housing;

[0046] The electrical interface connector is a board-to-board plug-in high-density connector;

[0047] The electrical interface connector is soldered to the PCB board using the SMT method.

[0048] The NPO light engine according to the embodiment of the present invention has at least one of the following advantages or at least a part of at least one of the advantages:

[0049] 1) In the NPO light engine, the transmitting end metal heat sink and the light transmitting component are placed together in the transmitting end loading slot of the PCB board, and the receiving end metal heat sink and the light receiving component are placed together in the receiving end loading slot of the PCB board; two electrical interface connectors are placed on both sides of the bottom layer of the PCB board, and the microcontroller circuit is placed in the middle of the two electrical interface connectors. Such a structural layout can reduce the volume and disperse the locations of the components that need heat dissipation;

[0050] 2) In the NPO light engine, a plug-in electrical interface connector is provided at the bottom of the PCB board, so that the thickness of the PCB board is not limited, and the thickness of the metal heat sink at the transmitting end and the metal heat sink at the receiving end can be increased. In addition, an upward heat dissipation method is adopted and multiple copper leakage areas are provided on the PCB board. Heat dissipation vias are added in the copper leakage areas and the copper paste plugging process is used to improve the heat dissipation efficiency, so that the laser light source is built into the NPO light engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] These and / or other aspects and advantages of the present invention will become apparent and readily understood from the following description of the preferred embodiments in conjunction with the accompanying drawings, in which:

[0052] Figure 1 is a schematic diagram of the three-dimensional structure of an NPO light engine according to an embodiment of the present invention;

[0053] Figure 2 yes Figure 1 A side view of the NPO light engine shown;

[0054] Figure 3 yes Figure 1 The schematic diagram of the structure of the NPO light engine without the outer shell is shown;

[0055] Figure 4 yes Figure 2 A bottom view of the NPO light engine shown;

[0056] Figure 5 yes Figure 1 The schematic diagram of the structure of the PCB board of the NPO light engine shown;

[0057] Figure 6 yes Figure 5 A schematic diagram of the structure of the copper leakage area and heat dissipation vias on the PCB board shown;

[0058] Figure 7 yes Figure 3 The schematic diagram of the structure of the metal heat sink at the transmitting end is shown;

[0059] Figure 8 yes Figure 3 The schematic diagram of the structure of the metal heat sink at the receiving end is shown;

[0060] Fig. 9 yes Figure 3 A schematic cross-sectional view of a light emitting component of an NPO light engine shown;

[0061] Fig.10 yes Figure 3 A schematic diagram of the connection relationship of the various components of the NPO light engine shown;

[0062] Fig.11 yes Figure 5 A schematic cross-sectional view of the stack-up of a PCB board is shown. DETAILED DESCRIPTION

[0063] The technical solution of the present invention is further specifically described below by examples and in conjunction with the accompanying drawings. In the specification, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the overall inventive concept of the present invention and should not be construed as a limitation of the present invention.

[0064] In view of the technical problems raised in the background technology section, the purpose of the present invention is to provide an NPO optical engine. First of all, the meaning of NPO (Near package optics) in the NPO optical engine is explained here: near package optics, the electrical interface connector for external connection is placed at the bottom of the optical engine, and the electrical interface connector uses a high-density board-to-board plug-in connector. The NPO optical engine has the advantages of short transmission and transmission signal link distance of the CPO packaging method, and also has the advantages of pluggable gold fingers that can be disassembled and assembled at any time.

[0065] See also Figures 1 to 4 , shows a schematic diagram of the structure of an NPO light engine according to an embodiment of the present invention. Specifically, the NPO light engine 100 includes five main components, namely, an electrical interface connector 10, a microcontroller circuit 20, an optical transceiver assembly 30, a metal heat sink 40, and a PCB board 50. It can be understood that the NPO light engine may also include a metal housing 60, which is configured to have a function of preventing EMI electromagnetic wave leakage or shielding it.

[0066] Further, see Figure 2The electrical interface connector 10 includes a male connector 11 for connecting high-speed transceiver signals and a female connector 12 for connecting power and control and debugging signals. The male connector 11 and the female connector 12 are arranged side by side on both sides of one end of the lower surface of the PCB board 50; the microcontroller circuit 20 is located between the male connector 11 and the female connector 12. Such an arrangement can reduce the interference of power and low-frequency control signals on high-speed transceiver signals.

[0067] In one embodiment, see Figure 3 The optical transceiver assembly 30 includes an optical transmitting array 31, an optical receiving array 32 and an optical fiber array assembly 33 respectively connected thereto. A microcontroller circuit 20 and an electrical interface connector 10 are disposed on the lower surface of the PCB board 50.

[0068] It should be noted that the optical transmitting component 31 includes: a laser light source 312, a silicon-based modulator 313 and a driver 314. The laser light source 312 includes a laser 312a, a first lens 312b, an optical isolator 312c and a second lens 312d arranged in sequence on the upper surface of the PCB board 50. The optical receiving component 32 includes a detector 321 and a transimpedance amplifier 322.

[0069] As described above, in the device layout of the NPO optical engine of the present invention, the optical transceiver assembly 30 and the metal heat sink 40 are arranged on the upper surface of the PCB board 50, and the electrical interface connector 10 and the microcontroller circuit 20 are arranged on the lower surface of the PCB board 50.

[0070] See also Figure 4 Regarding the structural arrangement of the lower surface of the PCB board 50, a fully shielded shell 61 and 62 may be arranged around the male connector 11 and the female connector 12 to prevent EMI electromagnetic wave leakage as much as possible. That is to say, in the embodiment of the present invention, the shape and material of the metal shell 60 are not limited as long as they can play the above-mentioned functional role.

[0071] In an alternative embodiment, the lower surface of the PCB board 50 may not be provided with a mechanical structural component such as the metal shell 60 , that is, it is provided in an open form.

[0072] The electrical interface connector 10 of the NPO light engine adopts a board-to-board plug-in high-density connector, and the pad spacing thereon is only 0.35 mm. The electrical interface connector 10 is vertically oriented and is placed at both sides of the bottom of the PCB board 50. The electrical interface connector 10 adopts a bottom plug-in method so that the thickness of the PCB board 50 is not limited.

[0073] The male connector 11 and the female connector 12 in the two electrical interface connectors 10 can be used for connecting PCB boards to each other, and can also be used for connecting PCB boards to FPC soft boards, and are soldered to the PCB boards using the SMT method.

[0074] In the present invention, there are two external connection modes for the electrical interface connector 10 of the NPO light engine 100.

[0075] The first connection method is to directly vertically insert the NPO light engine 100 into the host end, that is, the male connector 11 of the NPO light engine 100 is plugged into the female connector of the host end, and the female connector 12 of the NPO light engine 100 is plugged into the male connector of the host end. The height of the connector after plugging is about 1.8mm. Since two connectors with different structures, the male connector and the female connector, are used, the light engine can be prevented from being plugged in reverse.

[0076] The second connection method is to use an FPC board adapter to connect, that is, to design another FPC board, one side of the FPC board has an interface corresponding to the electrical interface connector 10, and the other side of the FPC board can be designed according to specific needs. Since the high-speed receiving and transmitting signals and the power supply and control signals use two different types of connectors, such as a male connector and a female connector, different forms of connectors and different shapes of soft boards can be used in different stages of product design and development, such as firmware debugging, optical device coupling, power-on aging, bandwidth testing, eye diagram testing, etc.

[0077] In the NPO light engine provided in the embodiment of the present invention, a bottom plug-in packaging method is adopted, and a high-density plug-in connector is used for the electrical interface.

[0078] See also Figure 5 The upper surface of the PCB board 50 is provided with a blind groove for accommodating the metal heat sink 40. The metal heat sink 40 is provided with a plurality of loading steps of different heights, and each loading step is placed on the corresponding components of the optical transmitting and receiving assembly 30.

[0079] The blind grooves include a transmitting end loading groove 51 and a receiving end loading groove 52, which are arranged on the upper surface of the PCB board 50 and are used to accommodate the transmitting end metal heat sink 41 and the receiving end metal heat sink 42. That is, a groove is dug downward from the upper surface of the PCB board 50 by controlling the depth of the groove milling, and the depth of the groove is, for example, 0.8±0.1mm, and the remaining board thickness after the groove is not less than 0.5mm. By setting the blind groove, the required components can be placed on the entire lower surface of the PCB board 50. Generally, the total thickness of the PCB board 50 is set to 1.4mm. When a blind groove with a thickness of 0.8mm is set, the PCB board below the blind groove still has a remaining thickness of about 0.6mm, so it can be used for wiring.

[0080] The light emitting array 31 is placed on the transmitting end metal heat sink 41, and the light receiving array 32 is placed on the receiving end metal heat sink 42. The transmitting end loading slot 51 and the receiving end loading slot 52 are provided on the upper surface of the PCB board 50. The transmitting end metal heat sink 41 and the light emitting component 31 placed thereon are placed together in the transmitting end loading slot 51. Similarly, the receiving end metal heat sink 42 and the light receiving component 32 placed thereon are placed together in the receiving end loading slot 52.

[0081] Furthermore, edge copper leakage 55 is provided at the edge of the upper surface of the PCB board, and bottom surface copper leakage 53, 54 is provided at the bottom of the transmitting end loading slot 51 and the receiving end loading slot 51. Similarly, upper surface copper leakage 56, 57 is provided at the position where the bottom of the heat conduction steps 411, 421 of the transmitting end metal heat sink 41 and the receiving end metal heat sink 42 contact the upper surface of the PCB board 50.

[0082] As shown in the figure, three screw holes 58 are provided on both sides of the PCB board 50 for fixed connection with the metal housing 60. Specifically, one screw hole 58 is provided on the right side as shown in the figure, and two spaced screw holes 58 are provided on the left side. Of course, those skilled in the art can select a suitable number of screw holes 58 and a suitable fixing method according to needs, and are not limited to the specific method described in the present invention.

[0083] In this embodiment, the structural layout of the NPO light engine 100 is as follows: the light emitting component 31 is placed on the metal heat sink 41 at the transmitting end, the light receiving component 32 is placed on the metal heat sink 42 at the receiving end, the metal heat sink 41 at the transmitting end and the light emitting component 31 are placed together in the transmitting end loading slot 51 of the PCB board 50, and the metal heat sink 42 at the receiving end and the light receiving component 32 are placed together in the receiving end loading slot 52 of the PCB board 50. Two electrical interface connectors (i.e., male connector 11 and female connector 12) are placed on both sides of the bottom layer of the PCB board 50, and the microcontroller circuit 20 is placed in the middle of the two electrical interface connectors.

[0084] Such a structural layout can reduce the volume, and the locations of the components that need heat dissipation are dispersed. Above the optical transceiver assembly 30 is the metal shell 60 of the NPO light engine 100. Except for the optical fiber array assembly 33 extending through the notch of the metal shell 60, the other optical components are sealed in the metal shell 60 for protection. The metal shell 60 is fixed to the PCB board 50 using three screws 58.

[0085] See also Figure 6, upper surface copper leakage 56 and 57 may be provided on the upper surface of the PCB board corresponding to the edge copper leakage 55 of the PCB board 50, the transmitting end thermal conductive step 411 and the receiving end thermal conductive step 421, and multiple thermal conductive vias 59 may be provided. The thermal conductive vias 59 are formed by a copper paste plugging process, which can increase the heat transfer efficiency between the layers of the PCB board.

[0086] See also Figure 7 , shows a schematic diagram of the structure of a transmitter metal heat sink 41 according to an embodiment of the present invention. A transmitter heat conduction step 411 is provided on one side (e.g., the upper side shown in the figure) of the transmitter metal heat sink 41. In addition to the transmitter heat conduction step 411, the transmitter metal heat sink 41 also includes a laser light source loading step 412, a silicon-based modulator loading step 413, and a driver loading step 414 arranged in sequence at different heights.

[0087] Further, the laser light source loading step 412 also includes a laser loading step 412a, a first lens loading step 412b, an optical isolator loading step 412c and a second lens loading step 412d of different heights. As shown in the figure, the first lens loading step 412b and the second lens loading step 412d can be set to the same step or different steps with the same height.

[0088] In addition, a thermally conductive gel 411a may be provided on the emitting end thermally conductive step 411, for example, the thermally conductive gel 411a is provided in the middle position of the emitting end thermally conductive step 411, and of course, it may also be arranged at other positions or on the entire surface of the emitting end thermally conductive step 411 as required.

[0089] See also Figure 8 , shows a schematic diagram of the structure of a receiving end metal heat sink 42 according to an embodiment of the present invention. A receiving end thermal conductive step 421 is provided on one side (e.g., the upper side shown in the figure) of the receiving end metal heat sink 42. In addition to the receiving end thermal conductive step 421, the receiving end metal heat sink 42 also includes a detector loading step 422 and a transimpedance amplifier loading step 423. Of course, if the height of the detector 321 and the transimpedance amplifier 322 are the same, the detector loading step 422 and the transimpedance amplifier loading step 423 can also be set to the same loading step with the same height. That is, those skilled in the art can make a choice according to their needs.

[0090] In addition, a thermally conductive gel 421a may be provided on the receiving end thermally conductive step 421, for example, the thermally conductive gel 421a is provided in the middle position of the transmitting end thermally conductive step 421, and of course, it may also be arranged at other positions or on the entire surface of the transmitting end thermally conductive step 421 as required.

[0091] Return to Combine Figure 3As shown, the laser light source 312, the silicon-based modulator 313 and the driver 314 are respectively located on the laser light source loading step 412, the silicon-based modulator loading step 413 and the driver loading step 414. Further, the laser 312a, the first lens 312b, the optical isolator 312c and the second lens 312d arranged in sequence on the upper surface of the PCB board 50 are respectively located on the laser loading step 412a, the first lens loading step 412b, the optical isolator loading step 412c and the second lens loading step 412d of different heights. Generally, since the relative height between the various components in the laser light source 312 has strict requirements, this height requirement can be easily met by setting a plurality of different loading steps on the laser light source loading step 412.

[0092] Similarly, the light receiving assembly 32 includes a detector 321 and a transimpedance amplifier 322 , which are respectively disposed on a detector loading step 422 and a transimpedance amplifier loading step 423 .

[0093] As mentioned above, see Fig. 9 By digging blind grooves on the upper surface of the PCB board 50, the various devices thereon are sunk, and by setting the silicon-based modulator loading step 413 and the driver loading step 414 at different heights, the upper surfaces of the silicon-based modulator 313 and the driver 314 installed thereon can be made flush, and the heights of the detector loading step 422 and the transimpedance amplifier loading step 423 are set so that the upper surfaces of the detector 321 and the transimpedance amplifier 322 thereon are flush.

[0094] See also Fig. 9 and Fig.10 One end of the driver 314 is connected to the silicon-based modulator 313 through a gold wire 70, and the other end of the driver 314 is bonded to the wire bonding pad of the PCB board 50 through a gold wire. One end of the laser 312a is bonded to the wire bonding pad of the PCB board 50 through a gold wire 70. One end of the transimpedance amplifier 322 is connected to the detector 321 through a gold wire 70, and the other end is bonded to the wire bonding pad on the PCB board 50 through a gold wire 70.

[0095] In addition, the silicon-based modulator 313 is connected to the laser light source 312, and the microcontroller circuit 20 is also connected to the silicon-based modulator 313, the driver 314, the transimpedance amplifier 322, the laser light source 312 and the female connector 12 respectively.

[0096] In this embodiment, the gold wire 70 between the driver 314 and the silicon-based modulator 313, the gold wire 70 between the driver 314 and the PCB board 50, the gold wire 70 between the transimpedance amplifier 322 and the detector 321, and the gold wire 70 between the transimpedance amplifier 321 and the PCB board 50 are configured for high-speed signal transmission and reception.

[0097] Since the gold wire 70 cannot control the impedance and is an impedance discontinuity point for the entire high-speed transceiver link, the length of the gold wire 70 should be shortened as much as possible. The length of the gold wire 70 is the shortest only when the driver 314 is at the same height as the upper surface of the silicon-based modulator 313 and the driver 314 is at the same height as the wire bonding pad surface of the PCB board 50.

[0098] See also Fig.11 , shows a schematic cross-sectional view of a stack of layers of a PCB board 50 according to an embodiment of the present invention. The PCB board 50 is a stacked structure of 6 layers.

[0099] The transmitter loading slot 51 and the receiver loading slot 52 on the PCB board 50 are opened as blind slots, and the buried hole 805 in the area below the blind slot is processed by back drilling process. The high-speed signal line is the first layer L1 of the 6-layer stacking structure from the top; the reference layer is the second layer L2 of the 6-layer stacking structure from the top; the low-speed signal line is the third to sixth layers L3-L6 of the 6-layer stacking structure from the top.

[0100] By arranging the high-speed signal lines and the low-speed signal lines in layers, mutual interference is avoided. The vias 80 include four types: through holes 801 from the first layer to the sixth layer L1-L6, blind holes 802 from the first layer to the second layer L1-L2, blind holes 803 from the fifth layer to the sixth layer L5-L6, and buried holes 804 from the second layer to the fifth layer L2-L5. Since the surface of the PCB board 50 is provided with a transmitter loading slot 51 and a receiver loading slot 52, the buried holes 805 below the transmitter loading slot 51 and the receiver loading slot 52 need to be removed by back drilling process, and only the parts of the L4 and L5 layers and a little stump upward are retained.

[0101] The stacked 6-layer structure of the PCB board 50 increases the layout and wiring space of the PCB board 50 , simplifies the stacked structure of the PCB board 50 , and reduces the cost.

[0102] Therefore, the overall heat dissipation method of the NPO light engine 100 of the embodiment of the present invention is:

[0103] The thermal conductive steps 411 and 421 of the transmitting end metal heat sink 41 and the receiving end metal heat sink 42 extend upward from the blind groove of the PCB board 50 to the upper surface of the PCB board 50, and the bottom surfaces of the thermal conductive steps 411 and 421 are bonded to the upper surface of the PCB board 50. The upper surface leakage copper 56 and 57 are arranged on the PCB board 50 at the bonding position. Thermal conductive gel 411a and 421a are placed on the top of the thermal conductive steps 411 and 421. The thermal conductive gel 411a and 421a are connected to the inner side of the metal shell 60, and the heat is dissipated from the top of the metal shell 60 of the NPO light engine 100 through the metal shell 60.

[0104] In this embodiment, the thickness of the PCB board is not limited by providing a plug-in electrical interface connector, that is, a male connector 11 and a female connector 12, at the bottom of the PCB board 50. In addition, the thickness of the metal heat sink 41 at the transmitting end and the metal heat sink 42 at the receiving end can be increased, and an upward heat dissipation method is adopted and multiple copper leakage areas are provided on the PCB board 50, heat dissipation vias are added in the copper leakage areas, and copper paste plugging process is used for manufacturing, thereby improving the heat dissipation efficiency and realizing that the laser light source 312 is built into the NPO light engine 100.

[0105] In addition, the plug-in electrical interface connector 10 is easy to use. When in use, it is only necessary to insert the NPO light engine 100 into the corresponding connector, and it can be disassembled and assembled at any time.

[0106] Furthermore, during the development process, the interfaces used are brought out through the bottom high-density connectors such as the male connector 11 and the female connector 12, which facilitates the work of the design and development personnel and shortens the development cycle.

[0107] The NPO light engine according to the embodiment of the present invention has at least one of the following advantages or at least a part of at least one of the advantages:

[0108] 1) In the NPO light engine, the transmitting end metal heat sink 41 and the light transmitting component 31 are placed together in the transmitting end loading slot 51 of the PCB board 50, and the receiving end metal heat sink 42 and the light receiving component 32 are placed together in the receiving end loading slot 52 of the PCB board 50; two electrical interface connectors are placed on both sides of the bottom layer of the PCB board 50, and the microcontroller circuit 20 is placed in the middle of the two electrical interface connectors. Such a structural layout can reduce the volume and disperse the locations of the components that need heat dissipation;

[0109] 2) In the NPO light engine, by arranging a plug-in electrical interface connector, namely a male connector 11 and a female connector 12, at the bottom of the PCB board 50, the thickness of the PCB board is not limited, and the thickness of the metal heat sink 41 at the transmitting end and the metal heat sink 42 at the receiving end can be increased. In addition, an upward heat dissipation method is adopted and a plurality of copper leakage areas are arranged on the PCB board 50. Heat dissipation vias are added in the copper leakage areas and the copper paste plugging process is used for manufacturing, thereby improving the heat dissipation efficiency and realizing that the laser light source 312 is built into the NPO light engine 100.

[0110] Although some embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the present general inventive concept, the scope of which is defined by the claims and their equivalents.

Claims

1. A NPO light engine, characterized in that: The NPO light engine comprises: Electrical interface connector; Microcontroller circuits; An optical transceiver assembly, the optical transceiver assembly comprising an optical transmitting array, an optical receiving array and optical fiber array assemblies respectively connected thereto; A metal heat sink, wherein the metal heat sink comprises a transmitting end metal heat sink on which a light transmitting array is placed and a receiving end metal heat sink on which a light receiving array is placed; A PCB board, wherein a transmitting end metal heat sink and a receiving end metal heat sink are arranged on the upper surface of the PCB board, and a microcontroller circuit and an electrical interface connector are arranged on the lower surface of the PCB board.

2. The NPO light engine according to claim 1, characterized in that: The upper surface of the PCB board is provided with a blind groove for accommodating a metal heat sink. The metal heat sink is provided with a plurality of loading steps of different heights, and each loading step is placed on each of the components of the optical transmitting and receiving assembly.

3. The NPO light engine according to claim 2, characterized in that: The blind slot includes a transmitting end loading slot and a receiving end loading slot which are arranged on the upper surface of the PCB board and are used to accommodate the transmitting end metal heat sink and the receiving end metal heat sink respectively; Edge copper leakage is arranged at the edge of the upper surface of the PCB board, and bottom copper leakage is arranged at the bottom of the transmitting end loading slot and the receiving end loading slot.

4. The NPO light engine according to claim 3, characterized in that: The transmitting end loading slot is provided with a transmitting end metal heat sink and a light emitting component located on the light emitting end metal heat sink; A receiving end metal heat sink and a light receiving component located on the receiving end metal heat sink are arranged in the receiving end loading slot.

5. The NPO light engine according to any one of claims 1 to 4, characterized in that: The transmitting end metal heat sink and the receiving end metal heat sink are respectively provided with a transmitting end heat conduction step and a receiving end heat conduction step; In addition to the emitting end heat conduction step, the emitting end metal heat sink also includes a laser light source loading step, a silicon-based modulator loading step and a driver loading step arranged in sequence at different heights; In addition to the receiving end heat conduction step, the receiving end metal heat sink also includes a detector loading step and a transimpedance amplifier loading step.

6. The NPO light engine according to claim 5, characterized in that: The optical emission assembly comprises: a laser light source, a silicon-based modulator and a driver, which are respectively located on the laser light source loading step, the silicon-based modulator loading step and the driver loading step; The laser light source comprises: a laser, a first lens, an optical isolator and a second lens which are sequentially arranged on the upper surface of a PCB board and are respectively located on a laser loading step, a first lens loading step, an optical isolator loading step and a second lens loading step of different heights.

7. The NPO light engine according to claim 6, characterized in that: One end of the driver is connected to the silicon-based modulator through a gold wire, and the other end of the driver is bonded to the wire bonding pad of the PCB board through a gold wire. The silicon-based modulator is connected to the laser light source. The microcontrol circuit is also connected to the silicon-based modulator, the driver, the transimpedance amplifier, the laser and the female connector respectively; One end of the laser is bonded to a wire bonding pad of a PCB board through a gold wire.

8. The NPO light engine according to claim 7, characterized in that: The light receiving assembly includes a detector and a transimpedance amplifier, which are respectively arranged on the detector loading step and the transimpedance amplifier loading step. One end of the transimpedance amplifier is connected to the detector gold wire, and the other end is bonded to the wire bonding pad on the PCB board through the gold wire.

9. The NPO light engine according to claim 8, characterized in that: The gold wires between the driver and the silicon-based modulator, the gold wires between the driver and the PCB board, the gold wires between the transimpedance amplifier and the detector, and the gold wires between the transimpedance amplifier and the PCB board are arranged for high-speed signal transmission and reception.

10. The NPO light engine according to claim 9, characterized in that: The upper surface of the driver is flush with the upper surface of the silicon-based modulator, and the upper surface of the detector is flush with the upper surface of the transimpedance amplifier.

11. The NPO light engine according to claim 10, characterized in that: The NPO light engine also includes a metal housing; The heat conduction steps of the transmitting end metal heat sink and the receiving end metal heat sink extend upward from the blind groove of the PCB board to the upper surface of the PCB board, the bottom surface of the heat conduction step is bonded to the upper surface of the PCB board, the PCB board at the bonding position is provided with an upper surface copper leak, and a heat conduction gel is placed on the top of the heat conduction step, the heat conduction gel is connected to the inner side of the metal shell, and the heat is dissipated from the top of the metal shell of the NPO light engine through the metal shell; At least one of the edge copper leakage, the upper surface copper leakage and the bottom surface copper leakage is provided with a thermal conductive via hole, and the thermal conductive via hole is formed by a copper paste plugging process.

12. The NPO light engine according to claim 10, characterized in that: The PCB board has a 6-layer stacked structure. The PCB board adopts a first-order HDI drilling method to form a blind groove; The via holes in the area below the blind slot are processed by back drilling process; The high-speed signal line is the first layer of the 6-layer stacked structure from the top; The reference layer is the second layer from the top of the 6-layer stacked structure; The low-speed signal lines are the third to sixth layers from the top of the six-layer stacked structure.

13. The NPO light engine according to claim 11, characterized in that: The electrical interface connector includes a male connector for connecting high-speed transceiver signals and a female connector for connecting power and control and debugging signals, and the male connector and the female connector are arranged side by side on both sides of one end of the lower surface of the PCB board; The micro-control circuit is located between the male connector and the female connector.

14. The NPO light engine according to claim 12, characterized in that: The male connector pair of the NPO light engine is plugged into the female connector of the host end, and the female connector pair of the NPO light engine is plugged into the male connector of the host end; or The male connector and the female connector of the NPO light engine are connected to one end of the FPC soft board through a transfer connection.

15. The NPO light engine according to claim 14, characterized in that: The PCB board is fixedly connected to the metal housing through screw holes; wherein the optical fiber array assembly extends through a notch in the metal housing; The electrical interface connector is a board-to-board plug-in high-density connector; The electrical interface connector is soldered to the PCB board using the SMT method.

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