A high-compatibility optical power sampling monitoring circuit and method

Abstract

The present invention discloses a high-compatibility optical power sampling monitoring circuit and method, the circuit includes a controller, a driver, a laser, a PNP tube mirror circuit, an NPN tube mirror circuit, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor and a sixth resistor; the controller is connected to the first end of the driver; the second end of the driver is connected to the first end of the laser through the fourth resistor, and the fourth end of the driver is connected to the first end of the PNP tube mirror circuit through the first resistor; the second end of the PNP tube mirror circuit is connected to the third end of the laser through the fifth resistor; the first end of the NPN tube mirror circuit is connected between the driver and the PNP tube mirror circuit through the second resistor, and is connected between the PNP tube mirror circuit and the laser through the third resistor; the second end of the NPN tube mirror circuit is connected to the third end of the laser through the sixth resistor. The present invention realizes current sampling solutions of different modes, increases product compatibility, and reduces development costs.

Description

Technical Field

[0001] The present invention relates to the field of optical fiber communication technology, and in particular to a high-compatibility optical power sampling monitoring circuit and method. Background Art

[0002] PD (Photo-Diode) is mainly used in optical modules to monitor the size of the transmitted optical power, realize the APC (Automatic Optical Power Control) function and provide the DDMI (Digital Diagnostic Monitoring Interface) of the transmitted optical power. Among them, the APC function maintains the stability of the transmitted optical power by setting the target monitoring current, and then dynamically adjusts the bias current of the LD (Laser Diode) according to the backlight current of the PD obtained by sampling to control the light emission size, so that the sampling current is close to the target monitoring current. The transmitted optical power monitoring is to read the size of the driver chip (driver) ADC value through the MCU (Micro Controller Unit) through the IIC (Inter-Integrated Circuit), and then update and store it in the corresponding protocol area in real time after conversion by the MCU.

[0003] At present, in the application of optical modules, firstly, different device manufacturers have different definitions of PD pins. There are two common wiring methods, one of which is to connect the PD anode to GND, and the other is to connect the PD cathode to GND. Different circuit designs are required to drive, resulting in repeated board making, which greatly increases product development costs. Secondly, although the driver chips provided by most manufacturers support both Sink and Source current sampling modes, there are still a few manufacturers whose driver chips only support Sink current sampling mode, and the common design is to achieve optical power monitoring through ADC voltage sampling. This method cannot achieve the APC function to control optical power.

[0004] In view of this, it is necessary to design a high compatibility circuit to solve the defects in the prior art. Summary of the invention

[0005] The present invention provides a high-compatibility optical power sampling monitoring circuit and method to solve the deficiencies of the prior art.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a high-compatibility optical power sampling and monitoring circuit, including a controller, a driver, a laser, a PNP tube mirror circuit, an NPN tube mirror circuit, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor;

[0008] The controller is connected to the first end of the driver;

[0009] The second end of the driver is connected to the first end of the laser through the fourth resistor, the third end of the driver is connected to the second end of the laser, and the fourth end of the driver is connected to the first end of the PNP tube mirror circuit through the first resistor;

[0010] The second end of the PNP tube mirror circuit is connected to the third end of the laser through the fifth resistor;

[0011] The first end of the NPN tube mirror circuit is connected between the driver and the PNP tube mirror circuit through the second resistor, and is connected between the PNP tube mirror circuit and the laser through the third resistor; the second end of the NPN tube mirror circuit is connected to the third end of the laser through the sixth resistor.

[0012] Further, in the high-compatibility optical power sampling and monitoring circuit, the PNP tube mirror circuit includes a first PNP tube and a second PNP tube;

[0013] The emitter of the first PNP tube and the emitter of the second PNP tube are connected in parallel and then connected to the positive electrode of the power supply;

[0014] The collector and base of the first PNP tube are respectively connected to the fifth resistor;

[0015] The collector of the second PNP tube is connected to the second resistor, and the base of the second PNP tube is connected to the fifth resistor.

[0016] Furthermore, in the high-compatibility optical power sampling and monitoring circuit, the characteristics of the first PNP tube and the second PNP tube are consistent.

[0017] Further, in the high-compatibility optical power sampling and monitoring circuit, the NPN tube mirror circuit includes a first NPN tube and a second NPN tube;

[0018] The emitter of the first NPN tube and the emitter of the second NPN tube are connected in parallel to a negative voltage conversion circuit; the negative voltage conversion circuit is used to generate a negative power supply voltage;

[0019] The collector of the first NPN transistor is connected to the third resistor, and the base of the first NPN transistor is connected to the sixth resistor;

[0020] The collector and the base of the second NPN tube are respectively connected to the sixth resistor.

[0021] Furthermore, in the high-compatibility optical power sampling and monitoring circuit, the first NPN transistor and the second NPN transistor have the same characteristics.

[0022] Further, in the high-compatibility optical power sampling and monitoring circuit, the driver includes a laser diode and a photodiode;

[0023] One end of the photodiode is grounded, and the other end is connected to the fifth resistor and the sixth resistor respectively;

[0024] The cathode of the laser diode is connected between the photodiode and the ground, and the anode of the laser diode is connected to the driver.

[0025] Furthermore, in the high-compatibility optical power sampling and monitoring circuit, the controller and the driver are connected via an I2C bus.

[0026] Furthermore, the high-compatibility optical power sampling and monitoring circuit further includes two pull-up resistors, namely a seventh resistor and an eighth resistor;

[0027] A first end of the seventh resistor is connected to the serial clock line in the I2C bus, and a second end thereof is connected to a positive power supply voltage;

[0028] A first end of the eighth resistor is connected to a serial data line in the I2C bus, and a second end of the eighth resistor is connected to a positive power supply voltage.

[0029] In a second aspect, an embodiment of the present invention provides a high-compatibility optical power sampling and monitoring method, which is performed by the high-compatibility optical power sampling and monitoring circuit as described in the first aspect above, and the method includes:

[0030] Determine whether the photodiode in the laser is anode-grounded or cathode-grounded, and determine whether the driver is in Sink current sampling mode or Source current sampling mode;

[0031] When the anode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the third resistor, the fourth resistor and the sixth resistor are disconnected, and the PNP tube mirror circuit works to support the Sink current sampling mode of the driver;

[0032] When the anode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the second resistor, the third resistor, the fifth resistor and the sixth resistor are disconnected, and the mPD is directly driven by the Source current sampling mode of the driver;

[0033] When the cathode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the third resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Source current sampling mode of the driver;

[0034] When the cathode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Sink current sampling mode of the driver.

[0035] The embodiments of the present invention provide a highly compatible optical power sampling monitoring circuit and method, which has a simple circuit design structure, takes into account the functional matching of different laser pin modes and drivers, and implements current sampling solutions in different modes. It does not require repeated board making, increases the compatibility of product development platforms, and reduces product development costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0037] Figure 1 It is a structural schematic diagram of a high-compatibility optical power sampling and monitoring circuit provided by an embodiment of the present invention;

[0038] Figure 2 It is a specific structural diagram of a high-compatibility optical power sampling and monitoring circuit provided by an embodiment of the present invention;

[0039] Figure 3 It is a flow chart of a high-compatibility optical power sampling and monitoring method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the description of the present invention, it is to be understood that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally disposed component. When a component is considered to be "disposed on" another component, it may be directly disposed on the other component or there may be a centrally disposed component.

[0042] In addition, terms such as "long", "short", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings and are only used to facilitate the description of the present invention. They do not indicate or imply that the device or component referred to must have this specific direction or operate with a specific direction structure, and should not be understood as a limitation of the present invention.

[0043] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0044] Embodiment 1

[0045] Please refer to Figure 1 and 2 , an embodiment of the present invention provides a high-compatibility optical power sampling and monitoring circuit, including a controller, a driver, a laser, a PNP tube mirror circuit, an NPN tube mirror circuit, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor and a sixth resistor;

[0046] The controller is connected to the first end of the driver;

[0047] The second end of the driver is connected to the first end of the laser through the fourth resistor, the third end of the driver is connected to the second end of the laser, and the fourth end of the driver is connected to the first end of the PNP tube mirror circuit through the first resistor;

[0048] The second end of the PNP tube mirror circuit is connected to the third end of the laser through the fifth resistor;

[0049] The first end of the NPN tube mirror circuit is connected between the driver and the PNP tube mirror circuit through the second resistor, and is connected between the PNP tube mirror circuit and the laser through the third resistor; the second end of the NPN tube mirror circuit is connected to the third end of the laser through the sixth resistor.

[0050] Wherein, the controller and the driver are connected via an I2C bus.

[0051] The driver includes a laser diode and a photodiode;

[0052] One end of the photodiode is grounded, and the other end is connected to the fifth resistor and the sixth resistor respectively;

[0053] The cathode of the laser diode is connected between the photodiode and the ground, and the anode of the laser diode is connected to the driver.

[0054] It should be noted that one of the functions of the present invention, namely the optical power monitoring function, is realized by the controller (referring to MCU, i.e. Figure 2 U4 in the figure) configures the driver (referring to Driver, i.e. Figure 2 The output bias current is controlled by the U3 register in the laser (J1) to drive the laser (J1) to emit light. The optical power is sampled by the photodiode (PD, specifically the backlight photodiode in this embodiment, MPD for short) and input to the driver's ADC. Then the MCU reads the driver's ADC register in real time through I2C, and stores it in the protocol storage address after conversion. When the transmitter is working normally, the test value of the optical power meter is Po, with K as a fixed coefficient that takes into account all other factors such as the backlight current conversion efficiency. Then the optical power is P O =I monitor K;

[0055] The optical transmitter manufacturer can obtain the K value through software calibration once during production. After the system is networked, there is no need to cut off the optical path for measurement to monitor the optical power in real time.

[0056] Another function is to constitute the APC function. The stability of the emitted light power is maintained by setting the target monitoring current. According to the backlight current of the sampled PD, the laser diode (LD) bias current is dynamically adjusted to control the light emission size, so that the sampling current is close to the target monitoring current.

[0057] Since the I2C drain is open-circuited, preferably, the high-compatibility optical power sampling and monitoring circuit must be provided with two pull-up resistors for realizing level inversion, which are the seventh resistor (R7) and the eighth resistor (R8);

[0058] A first end of the seventh resistor is connected to a serial clock line in the I2C bus, and a second end thereof is connected to a positive power supply voltage referenced to GND;

[0059] A first end of the eighth resistor is connected to a serial data line in the I2C bus, and a second end of the eighth resistor is connected to a positive power supply voltage referenced to GND.

[0060] In this embodiment, the PNP tube mirror circuit (i.e. Figure 2 U1) in the embodiment includes a first PNP transistor and a second PNP transistor;

[0061] The emitter of the first PNP tube and the emitter of the second PNP tube are connected in parallel and then connected to the positive electrode of the power supply;

[0062] The collector and base of the first PNP tube are respectively connected to the fifth resistor;

[0063] The collector of the second PNP tube is connected to the second resistor, and the base of the second PNP tube is connected to the fifth resistor.

[0064] The first PNP transistor and the second PNP transistor have the same characteristics.

[0065] In this embodiment, the NPN tube mirror circuit (i.e. Figure 2 U2) includes a first NPN tube and a second NPN tube;

[0066] The emitter of the first NPN tube and the emitter of the second NPN tube are connected in parallel and then connected to a negative voltage conversion circuit; the negative voltage conversion circuit is used to generate a negative power supply voltage (i.e., generate a negative power supply voltage such as Figure 2 The -Vcc voltage in the negative voltage conversion circuit Figure 2 Not shown); specifically, the positive voltage is converted into a negative voltage through a charge pump chip; the potential of the positive pole of the DC power supply is high, and the potential of the negative pole is low, and the current flows from the high potential to the low potential; the positive and negative power supplies are relative values, generally with the earth as the 0 point reference, the potential above this point is positive, and below this point is negative.

[0067] The collector of the first NPN transistor is connected to the third resistor, and the base of the first NPN transistor is connected to the sixth resistor;

[0068] The collector and the base of the second NPN tube are respectively connected to the sixth resistor.

[0069] The first NPN transistor and the second NPN transistor have the same characteristics.

[0070] The monitoring circuit design provided by the present invention first outputs through the NPN negative voltage pair tube mirror image, and then outputs through the PNP pair tube mirror image. It needs to go through two mirror images to achieve the purpose of changing the current direction. The specific principle is described as follows:

[0071] (1) When the PD anode is connected to GND and the cathode is used as the lead-out pin, it is input to the driver sampling ADC through the current mirror Sink. At this time, the circuit configuration is that the second resistor (R2), the third resistor (R3), the fourth resistor (R4) and the sixth resistor (R6) are disconnected, and the PNP tube mirror circuit works, supporting the driver current sampling Sink mode.

[0072] The circuit principle analysis and calculation are as follows:

[0073] Since the two PNP tubes (the first PNP tube and the second PNP tube) have the same characteristics, the voltage drop U EBO and U ECOThe first PNP tube always works in the amplification region. EBO Equal, so the base current and collector current of the first PNP tube and the second PNP tube are equal.

[0074]

[0075] When β>>2, I monitor =I MPD =I C .

[0076] (2) When the anode of the PD is connected to GND and the cathode is used as the lead-out pin, if the driver supports the Source current mode, the bias voltage can be directly provided to the PD. At this time, the peripheral circuit is the simplest. The circuit configuration is that the first resistor (R1), the second resistor (R2), the third resistor (R3), the fifth resistor (R5) and the sixth resistor (R6) are disconnected, and the mPD is directly driven through the driver current Source mode;

[0077] (3) When the cathode of the PD is connected to GND and the anode is used as the lead pin, a negative bias voltage needs to be provided to enable the PD to work normally. If the driver supports Source output current ADC sampling, the circuit configuration is that the first resistor (R1), the third resistor (R3), the fourth resistor (R4) and the fifth resistor (R5) are disconnected, and the negative voltage NPN tube mirror circuit works, supporting the driver current sampling Source mode;

[0078] The circuit principle analysis and calculation are as follows:

[0079] Since the two NPN tubes (the first NPN tube and the second NPN tube) have the same characteristics, the voltage drop U EBO and U ECO The first NPN tube always works in the amplification region. EBO Equal, so the base current and collector current of the first NPN tube and the second NPN tube are equal.

[0080]

[0081] When β>>2, I monitor =I MPD =I C .

[0082] (3) When the cathode of the PD is connected to GND and the anode is used as the lead pin, a negative bias voltage needs to be provided to enable the PD to work normally. If the driver supports Sink input current ADC sampling, the second resistor (R2), the fourth resistor (R4) and the fifth resistor (R5) are disconnected, the negative voltage NPN tube mirror circuit and the PNP tube mirror circuit work, and the driver current sampling Sink mode is supported.

[0083] An embodiment of the present invention provides a highly compatible optical power sampling and monitoring circuit with a simple circuit design structure. It takes into account the functional matching of different laser pin modes and drivers, realizes current sampling solutions in different modes, does not require repeated board making, increases the compatibility of product development platforms, and reduces product development costs.

[0084] Embodiment 2

[0085] Please refer to Figure 3 The embodiment of the present invention provides a high-compatibility optical power sampling and monitoring method, which is performed by the high-compatibility optical power sampling and monitoring circuit as described in the first embodiment. The method includes:

[0086] S201, determining whether the photodiode in the laser is anode-grounded or cathode-grounded, and determining whether the driver is in Sink current sampling mode or Source current sampling mode;

[0087] S202, when the anode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the third resistor, the fourth resistor and the sixth resistor are disconnected, and the PNP tube mirror circuit works to support the Sink current sampling mode of the driver;

[0088] S203, when the anode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the second resistor, the third resistor, the fifth resistor and the sixth resistor are disconnected, and the mPD is directly driven by the Source current sampling mode of the driver;

[0089] S204, when the cathode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the third resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Source current sampling mode of the driver;

[0090] S205. When the cathode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Sink current sampling mode of the driver.

[0091] The embodiment of the present invention provides a highly compatible optical power sampling and monitoring method, which has a simple circuit design structure, takes into account the functional matching of different laser pin modes and drivers, realizes current sampling solutions in different modes, does not require repeated board making, increases the compatibility of product development platforms, and reduces product development costs.

[0092] Thus far, the description of the above-described embodiments is provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the present disclosure. The individual elements or features of a specific embodiment are generally not subject to the limitations of the specific embodiment, but when applicable, they can be interchanged and used for selected embodiments even if not specifically shown or described. In many respects, the same element or feature also can be changed. This variation is not considered to be a departure from the present disclosure, and all such modifications are intended to be included in the scope of the present disclosure.

[0093] Example embodiments are provided so that the present disclosure will be thorough and the scope will be fully conveyed to those skilled in the art. In order to thoroughly understand the embodiments of the present disclosure, numerous details are set forth, such as examples of specific parts, devices, and methods. Obviously, for those skilled in the art, it is not necessary to use specific details, the example embodiments can be implemented in many different forms, and neither should be construed as limiting the scope of the present disclosure. In certain example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0094] Here, specialized vocabulary is used only for the purpose of describing specific example embodiments, and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "a" and "the" used herein may be intended to include plural forms as well. The terms "including" and "having" are inclusive, and therefore specify the presence of the claimed features, wholes, steps, operations, elements and / or components, but do not exclude the presence or additional presence of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof. Unless the order of execution is clearly indicated, the method steps, processing and operations described herein are not interpreted as necessarily needing to be performed in the specific order discussed and shown. It should also be understood that additional or optional steps may be adopted.

[0095] When an element or layer is referred to as being "on ...", "engaged with ...", "connected to" or "coupled to" another element or layer, it may be directly on another element or layer, engaged with another element or layer, connected to or coupled to another element or layer, or there may be an intervening element or layer. In contrast, when an element or layer is referred to as being "directly on ...", "directly engaged with ...", "directly connected to" or "directly coupled to" another element or layer, there may be no intervening element or layer. Other words used to describe element relationships should be interpreted in a similar manner (e.g., "between ..." and "directly between ...", "adjacent" and "directly adjacent", etc.). The term "and / or" used herein includes any and all combinations of one or more of the associated listed items. Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts are not limited by these terms. These terms may only be used to distinguish one element, component, region or part from another element, component, region or part. Unless clearly indicated by the context, the use of terms such as "first", "second" and other numerical terms herein does not imply sequence or order. Therefore, the first element, component, region, layer or part discussed below can adopt the terminology of the second element, component, region, layer or part without departing from the teaching of the exemplary embodiment.

[0096] Spatially relative terms, such as "inside", "outside", "below", "below...", "lower", "above", "upper", etc., may be used herein for ease of description to describe the relationship between one element or feature and one or more other elements or features as shown in the figure. Spatially relative terms may be meant to include different orientations of the device in addition to the orientation depicted in the figure. For example, if the device in the figure is flipped, the elements described as "below other elements or features" or "below elements or features" will be oriented as "above other elements or features". Therefore, the example term "below..." may include both upward and downward orientations. The device can be oriented in other ways (rotated 90 degrees or other orientations) and interpreted with the spatially relative descriptions herein.

Claims

1. A high-compatibility optical power sampling and monitoring circuit, characterized in that: It includes a controller, a driver, a laser, a PNP tube mirror circuit, an NPN tube mirror circuit, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor and a sixth resistor; The controller is connected to the first end of the driver; The second end of the driver is connected to the first end of the laser through the fourth resistor, the third end of the driver is connected to the second end of the laser, and the fourth end of the driver is connected to the first end of the PNP tube mirror circuit through the first resistor; The second end of the PNP tube mirror circuit is connected to the third end of the laser through the fifth resistor; The first end of the NPN tube mirror circuit is connected between the driver and the PNP tube mirror circuit through the second resistor, and is connected between the PNP tube mirror circuit and the laser through the third resistor; the second end of the NPN tube mirror circuit is connected to the third end of the laser through the sixth resistor; The laser includes a laser diode and a photodiode; One end of the photodiode is grounded, and the other end is connected to the fifth resistor and the sixth resistor respectively; The cathode of the laser diode is connected between the photodiode and the ground, and the anode of the laser diode is connected to the driver; The method performed by the high-compatibility optical power sampling and monitoring circuit includes: Determine whether the photodiode in the laser is anode-grounded or cathode-grounded, and determine whether the driver is in Sink current sampling mode or Source current sampling mode; When the anode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the third resistor, the fourth resistor and the sixth resistor are disconnected, and the PNP tube mirror circuit works to support the Sink current sampling mode of the driver; When the anode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the second resistor, the third resistor, the fifth resistor and the sixth resistor are disconnected, and the mPD is directly driven by the Source current sampling mode of the driver; When the cathode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the third resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Source current sampling mode of the driver; When the cathode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Sink current sampling mode of the driver.

2. The high-compatibility optical power sampling and monitoring circuit according to claim 1, characterized in that: The PNP tube mirror circuit includes a first PNP tube and a second PNP tube; The emitter of the first PNP tube and the emitter of the second PNP tube are connected in parallel and then connected to the positive electrode of the power supply; The collector and base of the first PNP tube are respectively connected to the fifth resistor; The collector of the second PNP tube is connected to the second resistor, and the base of the second PNP tube is connected to the fifth resistor.

3. The high-compatibility optical power sampling and monitoring circuit according to claim 2, characterized in that: The first PNP transistor and the second PNP transistor have the same characteristics.

4. The high-compatibility optical power sampling and monitoring circuit according to claim 2, characterized in that: The NPN tube mirror circuit includes a first NPN tube and a second NPN tube; The emitter of the first NPN tube and the emitter of the second NPN tube are connected in parallel to a negative voltage conversion circuit; the negative voltage conversion circuit is used to generate a negative power supply voltage; The collector of the first NPN transistor is connected to the third resistor, and the base of the first NPN transistor is connected to the sixth resistor; The collector and the base of the second NPN tube are respectively connected to the sixth resistor.

5. The high-compatibility optical power sampling and monitoring circuit according to claim 4, characterized in that: The first NPN transistor and the second NPN transistor have the same characteristics.

6. The high-compatibility optical power sampling and monitoring circuit according to claim 1, characterized in that: The controller and the driver are connected via an I2C bus.

7. The high-compatibility optical power sampling and monitoring circuit according to claim 6, characterized in that: Also included are two pull-up resistors, namely a seventh resistor and an eighth resistor; A first end of the seventh resistor is connected to the serial clock line in the I2C bus, and a second end thereof is connected to a positive power supply voltage; A first end of the eighth resistor is connected to a serial data line in the I2C bus, and a second end of the eighth resistor is connected to a positive power supply voltage.

8. A high-compatibility optical power sampling and monitoring method, implemented by the high-compatibility optical power sampling and monitoring circuit according to any one of claims 1 to 7, characterized in that: The method comprises: Determine whether the photodiode in the laser is anode-grounded or cathode-grounded, and determine whether the driver is in Sink current sampling mode or Source current sampling mode; When the anode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the third resistor, the fourth resistor and the sixth resistor are disconnected, and the PNP tube mirror circuit works to support the Sink current sampling mode of the driver; When the anode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the second resistor, the third resistor, the fifth resistor and the sixth resistor are disconnected, and the mPD is directly driven by the Source current sampling mode of the driver; When the cathode of the photodiode is grounded and the driver is in Source current sampling mode, the first resistor, the third resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Source current sampling mode of the driver; When the cathode of the photodiode is grounded and the driver is in the Sink current sampling mode, the second resistor, the fourth resistor and the fifth resistor are disconnected, and the NPN tube mirror circuit works to support the Sink current sampling mode of the driver.

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