CN113985537A

CN113985537A - Optical module

Info

Publication number: CN113985537A
Application number: CN202111273691.9A
Authority: CN
Inventors: 丁翔宇; 王凤来; �田�浩
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2021-10-29
Filing date: 2021-10-29
Publication date: 2022-01-28
Anticipated expiration: 2041-10-29
Also published as: CN113985537B

Abstract

The application discloses optical module includes: an upper housing; the lower shell is covered with the upper shell to form a wrapping cavity; the circuit board is arranged inside the wrapping cavity. And the laser bias circuit is arranged on the circuit board, one end of the laser bias circuit is connected with the laser, and the laser bias circuit is used for controlling the driving of the laser. And the MCU is arranged on the circuit board, and one end of the MCU is connected with the laser bias circuit and is used for controlling the output current of the laser bias circuit. Laser bias circuit is connected with MCU in this application, utilizes MCU control laser bias circuit's output current, carries out direct drive to the laser instrument through laser bias circuit. On the basis of the existing optical module hardware, an independently designed laser bias circuit is used for replacing an integrated laser driving chip, so that the circuit design is simplified, the module cost is reduced, and the dependence on the laser driving chip is eliminated.

Description

Optical module

Technical Field

The application relates to the technical field of communication, in particular to an optical module.

Background

With the development of new services and application modes such as cloud computing, mobile internet, video and the like, the development and progress of the optical communication technology become increasingly important. In the optical communication technology, an optical module is a tool for realizing the interconversion of optical signals and is one of key devices in optical communication equipment, and the transmission rate of the optical module is continuously increased along with the development requirement of the optical communication technology.

With the increase of communication speed, the speed requirement of the optical module is higher and higher, and especially in recent years, the optical module has a stricter limitation on the occupied space size, and it is required to implement more control schemes in a space range as small as possible.

Disclosure of Invention

The application provides an optical module to improve and reduce circuit board space.

In order to solve the technical problem, the embodiment of the application discloses the following technical scheme:

the embodiment of the application discloses an optical module, includes: an upper housing;

the lower shell is covered with the upper shell to form a wrapping cavity;

the circuit board set up in inside the parcel cavity:

the laser bias circuit is arranged on the circuit board, one end of the laser bias circuit is connected with the laser, and the laser bias circuit is used for controlling the driving of the laser;

and the MCU is arranged on the circuit board, and one end of the MCU is connected with the laser bias circuit and is used for controlling the output current of the laser bias circuit.

Compared with the prior art, the beneficial effects of the application are that:

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a diagram of an optical communication system connection according to some embodiments;

figure 2 is a block diagram of an optical network terminal according to some embodiments;

FIG. 3 is a patterning of a light module provided according to some embodiments;

FIG. 4 is an exploded block diagram of a light module according to some embodiments;

fig. 5 is a schematic diagram of a partial structure of an optical module used in the embodiment of the present application;

FIG. 6 is a partial signal flow diagram of an optical module for use in embodiments of the present application;

fig. 7 is a schematic diagram of a laser bias circuit according to the present application.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

In the optical communication technology, light is used to carry information to be transmitted, and an optical signal carrying the information is transmitted to information processing equipment such as a computer through information transmission equipment such as an optical fiber or an optical waveguide, so that the transmission of the information is completed. Because the optical signal has the passive transmission characteristic when being transmitted through the optical fiber or the optical waveguide, the information transmission with low cost and low loss can be realized. Further, since a signal transmitted by an information transmission device such as an optical fiber or an optical waveguide is an optical signal and a signal that can be recognized and processed by an information processing device such as a computer is an electrical signal, it is necessary to perform interconversion between the electrical signal and the optical signal in order to establish an information connection between the information transmission device such as an optical fiber or an optical waveguide and the information processing device such as a computer.

The optical module realizes the function of interconversion between the optical signal and the electrical signal in the technical field of optical fiber communication. The optical module comprises an optical port and an electrical port, the optical module realizes optical communication with information transmission equipment such as optical fibers or optical waveguides and the like through the optical port, realizes electrical connection with an optical network terminal (such as an optical modem) through the electrical port, and the electrical connection is mainly used for realizing power supply, I2C signal transmission, data signal transmission, grounding and the like; the optical network terminal transmits the electric signal to the computer and other information processing equipment through a network cable or a wireless fidelity (Wi-Fi).

Fig. 1 is a diagram of optical communication system connections according to some embodiments. As shown in fig. 1, the optical communication system mainly includes a remote server 1000, a local information processing device 2000, an optical network terminal 100, an optical module 200, an optical fiber 101, and a network cable 103;

one end of the optical fiber 101 is connected to the remote server 1000, and the other end is connected to the optical network terminal 100 through the optical module 200. The optical fiber itself can support long-distance signal transmission, for example, signal transmission of several kilometers (6 kilometers to 8 kilometers), on the basis of which if a repeater is used, ultra-long-distance transmission can be theoretically achieved. Therefore, in a typical optical communication system, the distance between the remote server 1000 and the optical network terminal 100 may be several kilometers, tens of kilometers, or hundreds of kilometers.

One end of the network cable 103 is connected to the local information processing device 2000, and the other end is connected to the optical network terminal 100. The local information processing apparatus 2000 may be any one or several of the following apparatuses: router, switch, computer, cell-phone, panel computer, TV set etc..

The physical distance between the remote server 1000 and the optical network terminal 100 is greater than the physical distance between the local information processing apparatus 2000 and the optical network terminal 100. The connection between the local information processing device 2000 and the remote server 1000 is completed by the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is completed by the optical module 200 and the optical network terminal 100.

The optical module 200 includes an optical port and an electrical port. The optical port is configured to connect with the optical fiber 101, so that the optical module 200 establishes a bidirectional optical signal connection with the optical fiber 101; the electrical port is configured to be accessed into the optical network terminal 100, so that the optical module 200 establishes a bidirectional electrical signal connection with the optical network terminal 100. The optical module 200 converts an optical signal and an electrical signal to each other, so that a connection is established between the optical fiber 101 and the optical network terminal 100. For example, an optical signal from the optical fiber 101 is converted into an electrical signal by the optical module 200 and then input to the optical network terminal 100, and an electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module 200 and input to the optical fiber 101.

The optical network terminal 100 includes a housing (housing) having a substantially rectangular parallelepiped shape, and an optical module interface 102 and a network cable interface 104 provided on the housing. The optical module interface 102 is configured to access the optical module 200, so that the optical network terminal 100 establishes a bidirectional electrical signal connection with the optical module 200; the network cable interface 104 is configured to access the network cable 103 such that the optical network terminal 100 establishes a bi-directional electrical signal connection with the network cable 103. The optical module 200 is connected to the network cable 103 via the optical network terminal 100. For example, the optical network terminal 100 transmits an electrical signal from the optical module 200 to the network cable 103, and transmits a signal from the network cable 103 to the optical module 200, so that the optical network terminal 100 can monitor the operation of the optical module 200 as an upper computer of the optical module 200. The upper computer of the Optical module 200 may include an Optical Line Terminal (OLT) and the like in addition to the Optical network Terminal 100.

The remote server 1000 establishes a bidirectional signal transmission channel with the local information processing device 2000 through the optical fiber 101, the optical module 200, the optical network terminal 100, and the network cable 103.

Fig. 2 is a structure diagram of an optical network terminal according to some embodiments, and fig. 2 only shows the structure of the optical module 200 of the optical network terminal 100 in order to clearly show the connection relationship between the optical module 200 and the optical network terminal 100. As shown in fig. 2, the optical network terminal 100 further includes a PCB circuit board 105 disposed in the housing, a cage 106 disposed on a surface of the PCB circuit board 105, and an electrical connector disposed inside the cage 106. The electrical connector is configured to access an electrical port of the optical module 200; the heat sink 107 has a projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into a cage 106 of the optical network terminal 100, the cage 106 holds the optical module 200, and heat generated by the optical module 200 is conducted to the cage 106 and then diffused by a heat sink 107. After the optical module 200 is inserted into the cage 106, an electrical port of the optical module 200 is connected to an electrical connector inside the cage 106, and thus the optical module 200 establishes a bidirectional electrical signal connection with the optical network terminal 100. Further, the optical port of the optical module 200 is connected to the optical fiber 101, and the optical module 200 establishes bidirectional electrical signal connection with the optical fiber 100.

Fig. 3 is a diagram of an optical module provided according to some embodiments, and fig. 4 is an exploded structural view of an optical module according to some embodiments. As shown in fig. 3 and 4, the optical module 200 includes a housing, a circuit board 300 disposed in the housing, and an optical transceiver;

the shell comprises an upper shell 201 and a lower shell 202, wherein the upper shell 201 is covered on the lower shell 202 to form the shell with two

openings

204 and 205; the outer contour of the housing generally appears square.

In some embodiments, the lower housing 202 includes a bottom plate and two lower side plates disposed at both sides of the bottom plate and perpendicular to the bottom plate; the upper housing 201 includes a cover plate, and two upper side plates disposed on two sides of the cover plate and perpendicular to the cover plate, and is combined with the two side plates by two side walls to cover the upper housing 201 on the lower housing 202.

The direction of the connecting line of the two

openings

204 and 205 may be the same as the length direction of the optical module 200, or may not be the same as the length direction of the optical module 200. For example, the opening 204 is located at an end (left end in fig. 3) of the optical module 200, and the opening 205 is also located at an end (right end in fig. 3) of the optical module 200. Alternatively, the opening 204 is located at an end of the optical module 200, and the opening 205 is located at a side of the optical module 200. Wherein, the opening 204 is an electrical port, and the gold finger of the circuit board 300 extends out of the electrical port 204 and is inserted into an upper computer (such as the optical network terminal 100); the opening 205 is an optical port configured to receive the external optical fiber 101, so that the optical fiber 101 is connected to an optical transceiver inside the optical module 200.

The upper shell 201 and the lower shell 202 are combined in an assembly mode, so that devices such as the circuit board 300 and the optical transceiver can be conveniently installed in the shells, and the upper shell 201 and the lower shell 202 can form packaging protection for the devices. In addition, when the devices such as the circuit board 300 are assembled, the positioning components, the heat dissipation components and the electromagnetic shielding components of the devices are convenient to arrange, and the automatic implementation production is facilitated.

In some embodiments, the upper housing 201 and the lower housing 202 are generally made of metal materials, which is beneficial to achieve electromagnetic shielding and heat dissipation.

In some embodiments, the optical module 200 further includes an unlocking component 203 located on an outer wall of a housing thereof, and the unlocking component 203 is configured to realize a fixed connection between the optical module 200 and an upper computer or release the fixed connection between the optical module 200 and the upper computer.

Illustratively, the unlocking member 203 is located on the outer wall of the two lower side plates 2022 of the lower housing 202, and includes a snap-fit member that mates with a cage of an upper computer (e.g., the cage 106 of the optical network terminal 100). When the optical module 200 is inserted into the cage of the upper computer, the optical module 200 is fixed in the cage of the upper computer by the engaging member of the unlocking member 203; when the unlocking member 203 is pulled, the engaging member of the unlocking member 203 moves along with the unlocking member, and the connection relationship between the engaging member and the upper computer is changed, so that the engagement relationship between the optical module 200 and the upper computer is released, and the optical module 200 can be drawn out from the cage of the upper computer.

The circuit board 300 includes circuit traces, electronic components (such as capacitors, resistors, triodes, and MOS transistors), and chips (such as MCU, laser driver chip, amplitude limiting amplifier chip, clock data recovery CDR, power management chip, and data processing chip DSP).

The circuit board 300 connects the above devices in the optical module 200 together according to circuit design through circuit routing to implement functions of power supply, electrical signal transmission, grounding, and the like.

The circuit board 300 is generally a rigid circuit board, which can also perform a bearing function due to its relatively rigid material, for example, the rigid circuit board can stably bear a chip; the hard circuit board can also be inserted into an electric connector in the cage of the upper computer, and in some embodiments disclosed in the application, a metal pin/golden finger is formed on the surface of the tail end of one side of the hard circuit board and is used for being connected with the electric connector; these are not easily implemented with flexible circuit boards.

Flexible circuit boards are also used in some optical modules; the flexible circuit board is generally used in combination with the rigid circuit board, and for example, the rigid circuit board may be connected to the optical transceiver device to supplement the rigid circuit board.

The optical transceiver comprises an optical transmitter subassembly and an optical receiver subassembly.

The optical transmitter sub-module is usually provided with a laser, and a laser driving chip is arranged for driving the laser, so that the peripheral power supply and control circuit of the current laser driving chip is complex, the occupied area of a PCB (printed circuit board) is large, and meanwhile, the optical transmitter sub-module has a single function and high cost, and is not beneficial to reducing the space occupancy rate and cost control of an optical module.

Fig. 5 is a schematic diagram of a partial structure of an optical module used in an embodiment of the present application, and fig. 6 is a schematic diagram of a partial signal flow of an optical module used in the embodiment of the present application. In order to solve the above problems, the present application provides an optical module, which has a circuit board with a gold finger at one end thereof, and is connected to an upper computer for receiving an electrical signal from the upper computer. The MCU302 is arranged on the circuit board, is connected with the golden finger, receives an electric signal from the upper computer, processes the electric signal and is used for controlling the data processing chip and the laser bias circuit.

The laser bias circuit 303 is connected to the MCU302, and receives a control signal from the MCU 302. The MCU302 outputs a signal to the laser bias circuit 303, which controls the magnitude of the output signal of the digital-to-analog converter. The laser bias circuit 303 is connected to the laser 401, and outputs a bias signal to drive the laser.

The laser 401 is an important component of the tosa,

the data processing chip 301 is arranged on the circuit board, is connected with the golden finger, receives the high-speed differential signal from the upper computer, processes the high-speed differential signal, outputs a modulation signal to the laser, and performs amplitude modulation on the laser.

The data processing chip 301 is also connected to the MCU302, and receives a control signal from the MCU 302. The MCU302 outputs a signal to the data processing chip 301 to control the output of the data processing chip 301. In the embodiment of the application, the optical module is connected with the upper computer through the golden finger on the circuit board, and receives the electric signal from the upper computer. The MCU302 is connected to the gold finger, receives the electrical signal, processes the electrical signal, and outputs an amplitude modulation signal and a control signal for controlling the data processing chip 301 and the laser bias circuit 303. The laser bias circuit 303 receives a control signal from the MCU302, outputs a bias signal value, and drives the laser 401. The data processing chip 301 receives the amplitude modulation data signal from the MCU302, performs data processing on the amplitude modulation data signal, outputs a modulation signal corresponding to the amplitude modulation data signal to the laser 401, and performs amplitude modulation on the laser 401. In the application, a laser driving chip which is complex, integrated and expensive is not needed, and the laser 401 is directly driven through the laser bias circuit 303. On the basis of the existing optical module hardware, an integrated laser driving chip is replaced by an independently designed laser biasing circuit 303, so that the circuit design is simplified, the module cost is reduced, and the dependence on the laser driving chip is eliminated.

In the embodiment of the application, the laser bias circuit is controlled by the MCU, and outputs the bias current in a specific range to drive the laser, so that the laser is kept on and works stably.

In some embodiments of the present application, an input end of the MCU302 is connected to the gold finger, and is configured to receive an electrical signal from an upper computer and process the electrical signal.

A first output terminal of the MCU302 is connected to the laser bias circuit 303, and controls an output voltage of the laser bias circuit 303. Specifically, the first output terminal of the MCU302 is a GPIO output terminal, and the output voltage and current of the laser bias circuit 303 are controlled by controlling the high and low levels.

The laser bias circuit 303 is arranged on the circuit board, the input end of the laser bias circuit 303 is connected with the first output end of the MCU302, the output end of the laser bias circuit 303 is connected with the laser 401, the laser 401 is directly driven, the configuration of a common laser driving chip and a related matching circuit of the laser driving chip is reduced, the occupied area of the circuit board space is favorably reduced, and the module integration level is improved.

Specifically, in this embodiment, the laser bias circuit 303 receives a first control signal output by a first output terminal of the MCU302, so as to control the output of the laser driving circuit.

Fig. 7 is a schematic diagram of a laser bias circuit provided in the present application, and as shown in fig. 7, the laser bias circuit includes: and the input end of the digital-to-analog converter (VDAC) is connected with the first output end of the MCU302, and converts the digital signal sent by the MCU into an analog signal. The amplifier Q1 has its non-inverting input terminal connected to the output terminal of the digital-to-analog converter, its inverting input terminal connected to ground, and its output terminal connected to the MOS transistor Q2. The source electrode of the MOS tube is connected with the matching resistor R and then grounded; the grid is connected with the output end of the amplifier Q1 for the input end, and the drain is connected with the laser, so that the laser is driven.

As shown in the figure, the MCU controls the output voltage Vout0 of the VDAC, and the voltage becomes Vout1 after being amplified by the amplifier Q1. Vout1 controls the conduction degree of MOS transistor Q2 and thus the output range of output current Ibias. Wherein, the resistor R is a matching resistor, protects the circuit and controls the maximum output range of Ibias.

In some embodiments of the present application, the first output terminal of the MCU is connected to the input terminal of the digital-to-analog converter, and outputs the digital control signal to the digital-to-analog converter. The digital-analog converter converts the digital control signal into an electric signal, outputs the electric signal to the amplifier, outputs the electric signal to the MOS tube after being amplified by the amplifier, and controls the output of the MOS tube. The drain electrode of the MOS tube is an output end and is connected with the slurry tube device to drive the laser.

Specifically, the laser is an electroabsorption modulated laser, and includes an electroabsorption modulator and a DFB laser, the data processing chip is connected to the electroabsorption modulator, and the laser bias circuit is connected to the DFB laser.

A second output end of the MCU302 is connected to the first input end of the data processing chip 301, and is configured to output a second control signal to the data processing chip 301 to drive the data processing chip 301.

The second input end of the data processing chip 301 is connected with the golden finger, receives the high-speed differential signal from the upper computer, processes the high-speed differential signal, outputs a modulation signal to the laser 401, and performs amplitude modulation on the laser 401.

The MCU302 receives an electric signal of the upper computer and outputs a first control signal and a second control signal, the laser bias circuit 303 receives the first control signal and outputs a laser driving signal to the laser 401, and the laser 401 is driven. The data processing chip 301 receives the second control signal, performs data processing according to the received high-speed differential signal of the upper computer, outputs a modulation signal to the laser 401, and performs amplitude modulation on the light of the laser 401. The laser 401 receives a laser drive signal and a modulation signal and outputs signal light. In the application, a laser bias circuit 303 is connected with an MCU302, the MCU302 is used for controlling the driving of the laser bias circuit 303 and a data processing chip 301, the data processing chip 301 is used for carrying out data processing according to a received high-speed differential signal of an upper computer, and a modulation signal is output to a laser 401; the laser bias circuit 303 controls the determination of the laser without a complicated, integrated and expensive laser driving chip, and the laser 401 is directly driven by the laser bias circuit 303. On the basis of the existing optical module hardware, an integrated laser driving chip is replaced by an independently designed laser biasing circuit 303, so that the circuit design is simplified, the module cost is reduced, and the dependence on the laser driving chip is eliminated.

MCU302 receives the signal of host computer, outputs first control signal and second control signal, and laser bias circuit 303 receives first control signal, outputs laser drive signal to the DFB laser instrument, realizes the drive to the DFB laser instrument, sends the light of not taking the signal. The data processing chip 301 receives the second control signal and starts working, the data processing chip 301 performs data processing according to the received high-speed differential signal of the upper computer, outputs a modulation signal to the electroabsorption modulator, performs amplitude modulation on light emitted by the DFB laser, and outputs signal light. In the application, a laser bias circuit is connected with an MCU302, the MCU302 is used for controlling the driving of the laser bias circuit 303 and a data processing chip 301, the data processing chip 301 is used for carrying out data processing according to a received high-speed differential signal of an upper computer, and a modulation signal is output to a laser; the laser bias circuit controls the determination of the laser, and the laser 401 is directly driven by the laser bias circuit 303 without a complicated, integrated and expensive laser driving chip. On the basis of the existing optical module hardware, an integrated laser driving chip is replaced by an independently designed laser biasing circuit 303, so that the circuit design is simplified, the module cost is reduced, and the dependence on the laser driving chip is eliminated.

Since the above embodiments are all described by referring to and combining with other embodiments, the same portions are provided between different embodiments, and the same and similar portions between the various embodiments in this specification may be referred to each other. And will not be described in detail herein.

It is noted that, in this specification, relational terms such as "first" and "second," and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a circuit structure, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such circuit structure, article, or apparatus. Without further limitation, the presence of an element identified by the phrase "comprising an … …" does not exclude the presence of other like elements in a circuit structure, article or device comprising the element.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the present disclosure. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

The above-described embodiments of the present application do not limit the scope of the present application.

Claims

1. A light module, comprising: an upper housing;

the lower shell is covered with the upper shell to form a wrapping cavity;

the circuit board set up in inside the parcel cavity:

the laser bias circuit is arranged on the circuit board, and one end of the laser bias circuit is connected with the laser to enable the laser to emit light;

the data processing chip is arranged on the circuit board, one end of the data processing chip is connected with the laser, and a modulation signal is output to the laser;

2. The optical module of claim 1, wherein the laser bias circuit is a DAC circuit.

3. The optical module of claim 1, further comprising: and the data processing chip is arranged on the circuit board and connected with the MCU, and the MCU controls the data processing chip.

4. The optical module of claim 1, wherein the laser is an electro-absorption modulated laser comprising an electro-absorption modulator and a DFB laser, the data processing chip is connected to the electro-absorption modulator, and the laser bias circuit is connected to the DFB laser.

5. The optical module of claim 3, wherein the data processing chip is further connected to the laser for amplitude modulating the laser.

6. The optical module according to claim 5, wherein the circuit board is provided with a gold finger for external connection;

the data processing chip is connected with the golden finger and used for receiving the high-speed differential signal, processing the high-speed differential signal and outputting a modulation signal.

7. The optical module of claim 6, wherein the MCU is connected with the laser through a GPIO output port.

8. The optical module of claim 6, wherein the MCU is connected with the data chip through a GPIO output port.