Micro-ring heat regulator with square root compression characteristic
By introducing a square root compression module and closed-loop control into the micro-ring thermal regulator, the nonlinearity problem of the micro-ring thermal regulator is solved, achieving high-precision and stable linear control, and improving the robustness and regulation accuracy of the system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-15
- Publication Date
- 2026-03-31
AI Technical Summary
The control and gain of existing micro-ring thermal regulators exhibit a nonlinear relationship, resulting in reduced regulation accuracy and insufficient system robustness.
A micro-ring thermal regulator with square root compression characteristics is adopted. By combining a digital-to-analog conversion module, a square root compression module, a drive module and a heating module, and using a negative feedback framework and a closed-loop control mechanism, a strict square root relationship between the output signal and the input signal is established to achieve linear control.
It significantly improves the adjustment accuracy and system robustness of the micro-ring thermal regulator, reduces dependence on the process, enhances the process consistency and overall stability of the circuit, and ensures the linear relationship between heating power and control signal.
Smart Images
Figure CN121763597A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of optoelectronic integrated circuit technology, and more specifically, relates to a micro-ring thermal regulator with square root compression characteristics. Background Technology
[0002] In the field of optoelectronic fusion and fully integrated technology, the microring resonator, as a core component, relies heavily on precise resonant wavelength alignment to achieve its function. However, the resonant wavelength is susceptible to drift due to factors such as ambient temperature fluctuations, manufacturing tolerances, and device aging, causing the open-loop system to malfunction.
[0003] The current mainstream approach applies regulating power through a micro-ring thermal regulator, utilizing the thermo-optical effect to compensate for wavelength drift. For example... Figure 1 The diagram shows the architecture of a conventional micro-ring thermal regulator, which consists of two main parts. The first part is a digital-to-analog conversion module (...). ), to realize control signals ( The second part is the driver module (digital-to-analog conversion). This amplifies the power of the control signal and outputs a large current. Heating resistors utilize the thermo-optic effect to support a wide range of resonant wavelength adjustment. However, in practical applications, a key challenge lies in the significant nonlinear relationship between the control signal output by the digital-to-analog converter module and the change in resonant wavelength, such as... Figure 2 As shown, the resonant wavelength in the microring ( The offset will depend on the power output from the drive module to the thermal resistor. The control signal output from the digital-to-analog converter exhibits a significant nonlinear relationship with the control signal output from the analog-to-digital converter. This results in a significantly higher regulation gain of the thermal regulator when the common-mode point is high, reducing regulation accuracy and compromising the robustness of the entire system. Summary of the Invention
[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a micro-ring thermal regulator with square root compression characteristics, which aims to solve the technical problem that the control and gain of the existing micro-ring thermal regulator are nonlinear.
[0005] This application relates to a micro-ring thermal regulator with square root compression characteristics, comprising a digital-to-analog converter module, a square root compression module, a drive module, and a heating module; the digital-to-analog converter module is used to convert received digital control signals into analog control signals and output them to the square root compression module; the square root compression module is used to solve for the square root of the analog control signal and output the square root as a square root signal to the drive module; the drive module is used to amplify the power based on the square root signal and drive the heating module to heat up; the heating module is used to heat the micro-ring waveguide.
[0006] Preferably, the square root compression module is based on a negative feedback architecture and uses a closed-loop control mechanism to make the output signal equal to the square root of the input signal.
[0007] Preferably, the square root compression module includes a comparator, a multiplier, and a closed-loop controller; The multiplier is used to calculate the square of the input signal X to obtain the signal Y, and outputs the signal Y to the comparator; The comparator is used to compare the magnitudes of the analog control signal and the signal Y, and sends the comparison result to the closed-loop controller; The closed-loop controller performs subsequent actions based on the comparison result: If the analog control signal is equal to signal Y, then signal X is output to the drive module as the square root signal; If the analog control signal is greater than signal Y, then signal X is added and the signal is output to the multiplier. If the analog control signal is less than signal Y, then the signal X is reduced and output to the multiplier.
[0008] Preferably, the multiplier is based on a cascaded dual digital-to-analog converter architecture.
[0009] Preferably, the multiplier includes an amplifier unit, a first digital-to-analog converter unit, and a second digital-to-analog converter unit; The digital signal input terminals of the first digital-to-analog converter and the second digital-to-analog converter are connected; the analog output terminal of the first digital-to-analog converter is connected to the input terminal of the amplifier unit, and the output terminal of the amplifier unit is connected to the reference level input terminal of the second digital-to-analog converter.
[0010] Preferably, the amplification gain of the amplifier unit satisfy:
[0011] in, The reference level is input to the reference level input terminal of the first digital-to-analog converter unit; The signal output from the analog output terminal of the second digital-to-analog converter unit satisfy:
[0012] in, This is the signal output from the analog output terminal of the first digital-to-analog converter unit.
[0013] Preferably, the comparator is a rail-to-rail input comparator.
[0014] Preferably, the driving module is a non-inverting proportional operational circuit based on a rail-to-rail operational amplifier.
[0015] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art: (1) The square root compression circuit constructed based on the negative feedback principle in this application establishes a strict mathematical square root relationship between the output and input through a closed-loop control mechanism, thereby fundamentally solving the nonlinearity problem of control signal and output power of traditional micro-ring thermal regulators from the system architecture level. Compared with the existing technical solutions, the square root compression method in this application has extremely high mathematical accuracy. As a result, when driving the heating module, the output heating power and the input control signal exhibit a highly linear relationship, providing an ideal linear control basis for the thermal tuning of the micro-ring waveguide.
[0016] (2) The square root compression circuit in this application is not sensitive to the specific parameters of the components due to its feedback mechanism, which significantly improves the process consistency and overall robustness of the circuit and gets rid of the dependence on specific processes.
[0017] (3) The square root compression circuit of this application adopts a multiplier with a dual DAC cascade architecture. Compared with the Girbert multiplier, it can guarantee a larger input / output dynamic range and give full play to the high linear output characteristics of the DAC, thereby ensuring the accuracy of the square root compression characteristics of the entire circuit at the system level. Compared with a purely digital multiplier, it also takes advantage of the analog output characteristics of the DAC, reducing the quantization error in the digital operation process.
[0018] (4) The rail-to-rail input comparator and rail-to-rail operational amplifier used in this application can support a wider input and output dynamic range. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of a traditional micro-ring thermal regulator.
[0020] Figure 2 This is a schematic diagram illustrating the nonlinearity introduced when using a traditional micro-ring thermal regulator for thermal coordination.
[0021] Figure 3 This is a schematic diagram of a micro-ring regulator with high-precision square root compression characteristics provided in Embodiment 1 of this application.
[0022] Figure 4 This is a schematic diagram of a micro-ring regulator with high-precision square root compression characteristics provided in Embodiment 2 of this application.
[0023] Figure 5 This is a diagram of a multiplier architecture with a dual DAC cascade structure provided in an embodiment of this application.
[0024] Figure 6This is a circuit test simulation diagram of the square root compression circuit provided in the embodiments of this application. Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0026] In this application, the terms "first" and "second," etc., are used to distinguish different objects, not to describe a specific order of objects. For example, "first digital-to-analog conversion unit" and "second digital-to-analog conversion unit," etc., are used to distinguish different digital-to-analog conversion units, not to describe a specific order of digital-to-analog conversion units.
[0027] In this application, the term "electrical connection" can refer to a direct circuit connection or a signal transmission via a communication protocol.
[0028] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.
[0029] In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more, for example, multiple processing units means two or more processing units, multiple elements means two or more elements, etc.
[0030] The embodiments of this application are described below with reference to the accompanying drawings.
[0031] like Figure 3 The image shows Embodiment 1 of this application. Embodiment 1 provides a micro-ring regulator with high-precision square root compression characteristics, which is used to drive the heating module to heat up according to the received digital control signal, thereby heating the micro-ring waveguide and compensating for wavelength drift.
[0032] Specifically, this includes: cascaded digital-to-analog conversion modules ( ), square root compression module, driver module ( ) and heating module.
[0033] The digital-to-analog converter module is used to convert the received digital control signals ( The digital-to-analog converter (DAC) converts the received digital feedback signal into an analog control signal and outputs it to the square root compression module. The DAC can employ a traditional architecture to achieve an optimal balance between adjustment accuracy and hardware overhead. In this embodiment, a current-steering DAC is selected to perform the digital-to-analog conversion, generating the corresponding analog control signal based on the received digital feedback signal.
[0034] The square root compression module is used to calculate the square root of the analog control signal and outputs it as the square root signal to the driver module. The square root compression module should have a wide input dynamic range to fully cover the output signal range of the digital-to-analog converter module, ensuring the system's applicability under all operating conditions. The square root compression module should also consider low power consumption and small area characteristics to meet the energy efficiency and size requirements of highly integrated optoelectronic fusion chips. In this embodiment, the square root compression module uses a square root compression circuit based on a negative feedback architecture. Through a closed-loop control mechanism, its output signal is mathematically strictly equal to the square root of the input signal, thereby achieving precise shaping of the output signal of the pre-amplifier DAC.
[0035] The driver module is used to amplify the power of the square root signal before outputting ( The heating module is heated to the required temperature. In this embodiment, a high-current output stage driving module is selected, and a high-current driving circuit is constructed using an operational amplifier to ensure that the output driving capability meets the power requirements of the micro-ring thermal tuner over a wide dynamic range.
[0036] The heating module is used to heat the microring waveguide.
[0037] The above multi-level structure works together to effectively solve the nonlinearity problem of traditional micro-ring regulators in thermal tuning applications while maintaining system stability.
[0038] like Figure 4 The image shows Embodiment 2 of this application, which also provides a micro-ring regulator with high-precision square root compression characteristics. It includes: a 10-bit current-type digital-to-analog converter module (…). ), square root compression module ( ), op-amp-based driver module ( ) and heating module.
[0039] The digital-to-analog converter module is used to convert the received digital control signals ( The digital-to-analog converter (DAC) converts the input signal into an analog control signal and outputs it to the square root compression module. In this embodiment, the DAC uses a traditional current-controlled DAC with a 4+4+2 architecture to implement segmented decoding. It converts the 10-bit digital input signal into the corresponding analog output to complete the digital-to-analog conversion function.
[0040] The square root compression module is used to acquire the square root of the analog control signal and output it to the drive module. Specifically, it is based on a negative feedback architecture, using a closed-loop control mechanism to make the output signal equal to the square root of the input signal. This includes a comparator, a multiplier, and a closed-loop controller. The multiplier calculates the square of the input signal X to obtain the signal Y, that is:
[0041] Then output signal Y to the comparator; The comparator compares the magnitudes of the analog control signal Vin and the signal Y, and sends the comparison result to the closed-loop controller. The closed-loop controller performs subsequent operations based on the comparison results: If the analog control signal Vin is equal to the signal Y, then the signal X will be output to the drive module as the square root signal; If the analog control signal Vin is greater than the signal Y, then the signal X is added and the signal is output to the multiplier. If the analog control signal Vin is less than the signal Y, then the signal X is reduced and output to the multiplier.
[0042] Based on the above process, the control signal X is gradually controlled to approach the square root of the analog control signal Vin before being output. This achieves the goal that the output signal of the square root compression module is mathematically exactly equal to the square root of the input signal.
[0043] The multiplier is based on a dual-DAC cascaded architecture. Compared to traditional Girbert multipliers, this multiplier guarantees a large input / output dynamic range and fully utilizes the high linearity of the DAC output, thus ensuring the accuracy of the square root compression characteristic of the entire loop at the system level. Compared to purely digital multipliers, it also leverages the analog output characteristics of the DAC, reducing quantization errors during digital computation.
[0044] like Figure 5 As shown, the multiplier includes an amplifier unit ( The system comprises a first DAC unit and a second DAC unit; the digital signal input terminals of the first DAC unit and the second DAC unit are connected; the analog output terminal of the first DAC unit is connected to the input terminal of the amplifier unit, and the output terminal of the amplifier unit is connected to the reference level input terminal of the second DAC unit.
[0045] Both the first and second DAC units are 10-bit to match the resolution of the digital-to-analog converter module. An amplifier unit is cascaded between the first and second DAC units. Its gain is... Let the reference level of the first DAC unit be... The digital input signals of the entire multiplier are Therefore, the output signal of the first DAC unit is:
[0046] The output of the first DAC unit will be used as the reference input of the second DAC unit; therefore, the output signal of the second DAC unit is:
[0047] Will Substituting will yield:
[0048] Note and The relationship, after substitution, is as follows:
[0049] Reasonable settings enable ,get:
[0050] Due to the approximation function of the comparator, we obtain
[0051] Will As the output signal of this square root compression module, it establishes its relationship with the input signal. There is a strict square root compression relationship between them. At this time, the analog control voltage signal output by the digital-to-analog converter module... After shaping by the square root compression module, the result will be
[0052]
[0053] Subsequently The output is sent to the driver module to achieve a large current output characteristic.
[0054] The driver module is used to amplify the power based on the square root signal, driving the heating module to heat up. Specifically, the driver module is a non-inverting proportional amplifier based on a rail-to-rail operational amplifier (the amplification ratio is set to 1 in the figure, i.e., a voltage follower), thereby achieving output power amplification. The rail-to-rail input-output characteristics can provide a large input dynamic range for the front-end circuit.
[0055] like Figure 6 As shown, the output characteristic test results of the micro-ring thermal regulator implemented in this application are as follows: When the input digital symbol step increases, under the precise control of the square root compression module, the common-mode level of its analog output signal increases accordingly, while the incremental slope decreases accordingly, which intuitively reflects the compression characteristics. To accurately characterize its linearization effect, the output signal... Perform the squaring operation, and the result is displayed as its square. It exhibits high linearity. This proves that when driving a heating module with a fixed resistance, the heating power of the heating module will have a highly linear relationship with the digital input symbols of the micro-ring thermal regulator, which provides an ideal linear control basis for the wavelength thermal tuning of the micro-ring waveguide.
[0056] It should be understood that expressions such as “comprising” and “may include” used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as “comprising” and / or “having” are to be interpreted as indicating a particular characteristic, number, operation, constituent element, component, or combination thereof, but not to exclude the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.
[0057] Furthermore, in this application, the expression "and / or" includes any and all combinations of the associated listed words. For example, the expression "A and / or B" may include A, may include B, or may include both A and B.
[0058] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. "Fixed connection" refers to a connection where the relative positional relationship remains unchanged after connection. "Rotary connection" refers to a connection where the components can rotate relative to each other after connection. "Sliding connection" refers to a connection where the components can slide relative to each other after connection. The directional terms mentioned in the embodiments of this application, such as "top," "bottom," "inner," "outer," "left," and "right," are only for reference to the directions in the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of this application, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0059] Furthermore, the mathematical concepts mentioned in the embodiments of this application, such as symmetry, equality, parallelism, and perpendicularity, are limitations specific to the current technological level, rather than absolute and strict mathematical definitions. Slight deviations are permissible; approximations of symmetry, equality, parallelism, and perpendicularity are all acceptable. For example, "A and B are parallel" means that A and B are parallel or approximately parallel, and the angle between A and B can be between 0 and 10 degrees. "A and B are perpendicular" means that A and B are perpendicular or approximately perpendicular, and the angle between A and B can be between 80 and 100 degrees.
[0060] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A micro-ring thermal regulator with square root compression characteristics, characterized in that, It includes a digital-to-analog conversion module, a square root compression module, a driving module, and a heating module; the digital-to-analog conversion module is used to convert the received digital control signal into an analog control signal and output it to the square root compression module; the square root compression module is used to solve for the square root of the analog control signal and output the square root as a square root signal to the driving module; the driving module is used to amplify the power based on the square root signal and drive the heating module to heat up; the heating module is used to heat the micro-ring waveguide.
2. The micro-ring thermal regulator according to claim 1, characterized in that, The square root compression module is based on a negative feedback architecture and uses a closed-loop control mechanism to make the output signal equal to the square root of the input signal.
3. The micro-ring thermal regulator according to claim 1 or 2, characterized in that, The square root compression module includes a comparator, a multiplier, and a closed-loop controller; The multiplier is used to calculate the square of the input signal X to obtain the signal Y, and outputs the signal Y to the comparator; The comparator is used to compare the magnitudes of the analog control signal and the signal Y, and sends the comparison result to the closed-loop controller; The closed-loop controller performs subsequent actions based on the comparison result: If the analog control signal is equal to signal Y, then signal X is output to the drive module as the square root signal; If the analog control signal is greater than signal Y, then signal X is added and the signal is output to the multiplier. If the analog control signal is less than signal Y, then the signal X is reduced and output to the multiplier.
4. The micro-ring thermal regulator according to claim 3, characterized in that, The multiplier is based on a cascaded architecture of dual digital-to-analog converters.
5. The micro-ring thermal regulator according to claim 3, characterized in that, The multiplier includes an amplifier unit, a first digital-to-analog converter unit, and a second digital-to-analog converter unit; The digital signal input terminals of the first digital-to-analog converter and the second digital-to-analog converter are connected; the analog output terminal of the first digital-to-analog converter is connected to the input terminal of the amplifier unit, and the output terminal of the amplifier unit is connected to the reference level input terminal of the second digital-to-analog converter.
6. The micro-ring thermal regulator according to claim 5, characterized in that, The amplification gain of the amplifier unit satisfy: in, The reference level is input to the reference level input terminal of the first digital-to-analog converter unit; The signal output from the analog output terminal of the second digital-to-analog converter unit satisfy: in, This is the signal output from the analog output terminal of the first digital-to-analog converter unit.
7. The micro-ring thermal regulator according to claim 3, characterized in that, The comparator is specifically a rail-to-rail input comparator.
8. The micro-ring thermal regulator according to claim 1, characterized in that, The driving module is specifically a non-inverting proportional operational circuit based on a rail-to-rail operational amplifier.