Optical module temperature monitoring and calibration method and device
Through the combination of temperature sensing chip and MCU, the linear relationship between the optical module Case temperature and PCBA temperature is used to realize real-time monitoring and calibration of the optical module temperature, solving the problem of performance deterioration of the optical module under non-standard temperatures and improving the temperature Accuracy and reliability of reporting.
Patent Information
- Application Number
- CN202110558283.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-05-21
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2041-05-21
AI Technical Summary
When the optical module exceeds the operating temperature range of 0℃~70℃, it may lead to performance deterioration and damage to internal components. Real-time monitoring of PCBA temperature and calibration of temperature reporting are required to control errors.
The temperature sensing chip monitors the PCBA temperature inside the optical module, the MCU calculates the PCBA temperature based on the output voltage, and uses the linear relationship between the optical module Case temperature and the PCBA temperature to obtain the final working temperature report, and uses the temperature calibration device to adjust the temperature calibration coefficient and Compensation value to reduce error.
Real-time monitoring and accurate reporting of the optical module temperature is realized, close to the actual working temperature to the maximum extent, and control the temperature error within a certain range, improving the accuracy and reliability of temperature reporting.
Smart Images
Figure CN113503986B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of optical modules, and in particular relates to an optical module temperature monitoring and calibration method and device. Background Art
[0002] The working temperature of the optical module is generally between 0℃ and 70℃. If it exceeds the working temperature range, the working performance and indicators of the optical module may deteriorate, and the internal components of the optical module may be damaged. Therefore, it is necessary to monitor the PCBA temperature inside the optical module in real time. Since the actual working temperature of the optical module is generally based on the case temperature (CaseTemperature) as the standard, it is necessary to measure the Case Temperature of the optical module to calibrate the temperature reported by the GUI software so that the temperature reporting error is controlled within a certain range. Summary of the invention
[0003] The object of the present invention is to provide an optical module temperature monitoring and calibration method and device, aiming to achieve real-time monitoring of the PCBA temperature inside the optical module and calibrate the reported temperature so that the temperature reporting error is controlled within a certain range.
[0004] The present invention is achieved in that:
[0005] In one aspect, the present invention provides a method for monitoring and calibrating the temperature of an optical module, comprising the following steps:
[0006] Get the optical module PCBA temperature and case temperature under different ambient temperatures;
[0007] Obtain the linear relationship between the optical module Case temperature and PCBA temperature according to the optical module PCBA temperature and Case temperature under different ambient temperatures;
[0008] The temperature of the PCBA inside the optical module is monitored through the temperature sensor chip. The MCU calculates the PCBA monitoring temperature based on the output voltage of the temperature sensor chip that changes with the PCBA temperature.
[0009] The optical module case temperature is obtained according to the optical module PCBA monitoring temperature and the linear relationship between the optical module case temperature and the PCBA temperature as the final optical module operating temperature report.
[0010] Furthermore, the linear relationship between the optical module Case temperature and PCBA temperature is as follows:
[0011] Temp=T*slope+offset
[0012] Among them, Temp is the Case temperature, T is the PCBA temperature, slope is the temperature calibration coefficient, and offset is the temperature compensation value.
[0013] On the other hand, the present invention also provides an optical module temperature monitoring and calibration device, including a test optical module, a temperature monitoring device, a temperature calibration device, and a computer with GUI software installed;
[0014] The temperature monitoring device includes a power chip, a temperature sensor chip and an MCU. The power chip is connected to the temperature sensor chip and the MCU to provide working voltage for the temperature sensor chip and the MCU. The temperature sensor chip is connected to the MCU. The output voltage of the temperature sensor chip changes with the temperature of the PCBA inside the test optical module. The MCU samples the output voltage of the temperature sensor chip in real time and calculates the PCBA monitoring temperature according to the output voltage and transmits it to the GUI software.
[0015] The temperature calibration device includes a test circuit board, a temperature-adjustable sealed box, and a spot thermometer, wherein the spot thermometer is fixed on the tube shell of the test optical module and is used to test the case temperature of the optical module, and the test optical module is inserted into the test circuit board and placed in the sealed box;
[0016] The temperature in the sealed box is changed to make the case temperature of the tested optical module vary between 0℃ and 70℃. By comparing the case temperature of the optical module measured by the spot thermometer at different box temperatures and the PCBA temperature obtained by the GUI software, the temperature calibration coefficient and temperature compensation value of the linear relationship between the case temperature and the PCBA temperature of the optical module in the GUI software are adjusted. The GUI software obtains the case temperature of the optical module based on the PCBA monitoring temperature and the linear relationship between the case temperature and the PCBA temperature for reporting.
[0017] Furthermore, the model of the power chip is ADP196, the model of the temperature sensor chip is LM94023BITM, and the model of the MCU is ADuC7023 or ADuCM320i.
[0018] Furthermore, the 2V5 voltage output by the VREF pin of the MCU is used to provide the working voltage for the temperature sensor chip. The relationship between the output voltage V of the temperature sensor chip and the PCBA temperature T is as follows:
[0019] V=-8.2(mV / ℃)*T(℃)+B
[0020] Where V is the output voltage, T is the PCBA temperature, and B is a constant;
[0021] The MCU calculates the PCBA monitoring temperature according to the output voltage using the above relationship.
[0022] Furthermore, the temperature calibration device also includes an analog optical module, an analog test circuit board and an optical fiber. The analog optical module is placed on the analog test circuit board. The test optical module and the analog optical module are connected via an optical fiber. After the analog optical module works normally, a PRBS code type is sent to the test optical module to provide the test optical module with a simulated normal working scenario.
[0023] Furthermore, the temperature calibration device also includes a first switching power supply and a second switching power supply, the first switching power supply is connected to the test circuit board and the test optical module, and is used to provide a working voltage for the test circuit board and the test optical module; the second switching power supply is connected to the analog circuit board and the analog optical module, and is used to provide a working voltage for the analog circuit board and the analog optical module.
[0024] Furthermore, the temperature-adjustable sealed box is a temperature-adjustable incubator.
[0025] Furthermore, the temperature-adjustable sealed box is a wooden sealed box, and the temperature inside the wooden sealed box is changed by a rapid temperature shock box.
[0026] Compared with the prior art, the present invention has the following beneficial effects:
[0027] The optical module temperature monitoring and calibration method and device provided by the present invention monitor the temperature of the PCBA inside the optical module through a temperature sensor chip, and the MCU calculates the PCBA monitoring temperature according to the output voltage of the temperature sensor chip that changes with the PCBA temperature, so as to realize real-time monitoring of the PCBA temperature of the optical module, and obtains the case temperature of the optical module as the final optical module operating temperature report according to the linear relationship between the PCBA monitoring temperature of the optical module and the case temperature of the optical module and the PCBA temperature, so that the reported temperature is as close to the actual operating temperature of the optical module as possible, and the temperature reporting error is controlled within a certain range, thereby improving the accuracy of the temperature reporting, and the method is simple and reliable. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 A circuit diagram of a temperature monitoring device provided by an embodiment of the present invention;
[0029] Figure 2 A schematic diagram of the structure of a temperature calibration device provided by an embodiment of the present invention;
[0030] Figure 3 The embodiment of the present invention provides a relationship between the voltage sampled by the MCU before and after calibration and the temperature reported by the GUI software. DETAILED DESCRIPTION
[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments 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.
[0032] An embodiment of the present invention provides an optical module temperature monitoring and calibration method, comprising the following steps:
[0033] S1. Obtain the PCBA temperature and Case temperature of the optical module under different ambient temperatures;
[0034] S2. Obtaining a linear relationship between the case temperature and the PCBA temperature of the optical module according to the PCBA temperature and the case temperature of the optical module under different ambient temperatures;
[0035] S3, monitor the temperature of the PCBA inside the optical module through the temperature sensor chip, and the MCU calculates the PCBA monitoring temperature according to the output voltage of the temperature sensor chip that changes with the PCBA temperature;
[0036] S4. According to the optical module PCBA monitoring temperature and the linear relationship between the optical module Case temperature and the PCBA temperature, the optical module Case temperature is obtained as the final optical module operating temperature report.
[0037] The optical module temperature monitoring and calibration method provided by the embodiment of the present invention monitors the temperature of the PCBA inside the optical module through the temperature sensor chip. The MCU calculates the PCBA monitoring temperature according to the output voltage of the temperature sensor chip that changes with the PCBA temperature, thereby realizing real-time monitoring of the PCBA temperature of the optical module. Since the actual working temperature of the optical module is generally based on the Case temperature, it is necessary to measure the Case temperature of the optical module to calibrate the originally reported PCBA temperature. The embodiment of the present invention obtains the Case temperature of the optical module as the final optical module working temperature report according to the PCBA monitoring temperature of the optical module and the linear relationship between the Case temperature of the optical module and the PCBA temperature, so that the reported temperature is as close to the actual working temperature of the optical module as possible, and the temperature reporting error is controlled within a certain range, thereby improving the accuracy of the temperature reporting, and the method is simple and reliable.
[0038] After extensive research, the inventors found that there is a linear relationship between the Case temperature of the optical module and the PCBA temperature obtained by the temperature sensor chip and the MCU, and the formula is as follows:
[0039] Temp=T*slope+offset
[0040] Among them, Temp is the Case temperature, T is the PCBA temperature, slope is the temperature calibration coefficient, and offset is the temperature compensation value.
[0041] Therefore, the above linear relationship can be used to obtain the case temperature of the optical module according to the PCBA temperature of the optical module as the final operating temperature report of the optical module.
[0042] To implement the above method, Figure 1 and Figure 2 As shown, an embodiment of the present invention further provides an optical module temperature monitoring and calibration device, including a test optical module, a temperature monitoring device, a temperature calibration device, and a computer with GUI software installed.
[0043] like Figure 1 As shown, the temperature monitoring device includes a power chip, a temperature sensor chip and an MCU. In this preferred embodiment, the power chip adopts ADI's power chip ADP196, the temperature sensor chip adopts TI's temperature sensor chip LM94023BITM, and the MCU adopts ADI's ADuC7023 or ADuCM320i series MCU chip. The MCU chip, the temperature sensor chip, and the power chip are all welded on the PCB inside the optical module. The power chip is connected to the temperature sensor chip and the MCU. The power chip provides a 3V3 power supply voltage to the MCU, and uses the 2V5 voltage output by the VREF pin of the MCU (the driving current of this pin of the MCU is 1mA) to provide a working voltage to the temperature sensor chip (the working current is microampere level). The temperature sensor chip is connected to the MCU, and the output voltage of the temperature sensor chip changes with the temperature of the PCBA inside the test optical module. The MCU samples the output voltage of the temperature sensor chip in real time and calculates the PCBA monitoring temperature according to the output voltage and transmits it to the GUI software.
[0044] The temperature sensor chip LM94023BITM has a very small package size and occupies a small PCB area. The operating voltage is between 1.5V and 5.5V, the typical operating current is 5.4uA, and it can operate in the range of -50℃ to 150℃. In the range of -50℃ to 150℃, the output voltage V of the temperature sensor chip LM94023BITM is linearly related to the temperature T. The MCU samples the output voltage V of the temperature sensor chip LM94023BITM, and by sampling different voltage values output in the temperature range of 0 to 70℃, through curve fitting, it can be concluded that the relationship between the output voltage V sampled by the MCU and the PCBA temperature T is linear:
[0045]
[0046] The unit of V is mV; the unit of T is ℃; (T1, V1) and (T2, V2) are any two points in the temperature range of 0 to 70℃.
[0047] When the GS pin of the temperature sensor chip LM94023BITM is connected to 2V5, that is, GS is high, the linear coefficient is -8.2mV / ℃, and the relationship between the output voltage V of the temperature sensor chip and the PCBA temperature T is as follows:
[0048] V=-8.2(mV / ℃)*T(℃)+B
[0049] Where V is the output voltage, T is the PCBA temperature, and B is a constant;
[0050] The MCU uses the above relationship to calculate the PCBA monitoring temperature according to the output voltage. In the range of 0-70°C, the accuracy error of the temperature T collected by the temperature sensor chip LM94023BITM is within ±1.8°C.
[0051] like Figure 2 As shown, the temperature calibration device includes a test circuit board, a temperature-adjustable sealed box and a spot thermometer. The spot thermometer is fixed on the tube shell of the test optical module and is used to test the case temperature of the optical module. Specifically, the wire end of the spot thermometer can be wrapped around the middle of the metal tube shell of the test optical module with high-temperature tape; the test optical module (1# optical module) is inserted into the test circuit board (1# test circuit board) and placed in a sealed box. The temperature-adjustable sealed box can be a temperature-adjustable incubator, or the temperature-adjustable sealed box is a wooden sealed box, and the temperature in the wooden sealed box is changed by a rapid temperature shock box. Preferably, the temperature calibration device also includes an analog optical module (2# optical module), an analog test circuit board (2# test circuit board) and an optical fiber. The analog optical module is placed on the analog test circuit board. The test optical module and the analog optical module are connected by an optical fiber. After the analog optical module works normally, a PRBS code type is sent to the test optical module to provide a simulated normal working scene for the test optical module. Furthermore, the temperature calibration device also includes a first switching power supply and a second switching power supply, the first switching power supply is connected to the test circuit board and the test optical module, and is used to provide a working voltage for the test circuit board and the test optical module; the second switching power supply is connected to the analog circuit board and the analog optical module, and is used to provide a working voltage for the analog circuit board and the analog optical module.
[0052] The temperature in the sealed box is changed to make the Case temperature of the tested optical module vary between 0℃ and 70℃. By comparing the Case temperature of the optical module measured by the spot thermometer at different box temperatures and the PCBA temperature obtained by the GUI software, the temperature calibration coefficient and temperature compensation value of the linear relationship between the Case temperature and the PCBA temperature of the optical module in the GUI software are adjusted. The GUI software obtains the Case temperature of the optical module according to the PCBA monitoring temperature and the linear relationship between the Case temperature and the PCBA temperature, and reports it. Finally, the monitoring temperature reported by the GUI software and the Case temperature of the optical module measured by the spot thermometer are basically consistent and within an acceptable error range.
[0053] Specifically, the test optical module on the test circuit board is accessed through the IIC using the USB interface of the computer. The reported temperature of the optical module can be monitored through the GUI software interface, and the temperature calibration coefficient and temperature compensation value of the optical module can be set. Before calibration, if there is a large difference between the monitoring temperature reported by the GUI software and the Case temperature of the optical module measured by the spot thermometer, it is necessary to adjust the temperature calibration coefficient and perform temperature compensation. According to the sampling characteristics of the MCU, the ADC sampling value Temp of the temperature reported by the GUI software and the ADC sampling value of the temperature T before calibration are linearly related, as shown in the following formula:
[0054] Temp=T*slope+offset
[0055] Slope is the temperature calibration coefficient, which can significantly change the temperature monitoring value; offset is the temperature compensation value, which can fine-tune the temperature monitoring value.
[0056] like Figure 3 As shown in the figure, the upper and lower straight lines are the relationship between the voltage V (mV) sampled by the MCU and the temperature T (℃) reported by the GUI software before and after calibration, respectively. The discrete points are the CASE temperatures of the optical module tested by the spot thermometer after calibration. It can be seen that the calibration error is small.
[0057] As shown in the following table, Monitor Temp (℃) is the reported temperature displayed by the GUI software, Case Real Temp (℃) is the actual optical module case temperature measured by the spot thermometer, and Error (℃) is the difference between the two.
[0058]
[0059] It can be seen from the above table that the error between the reported temperature displayed on the GUI and the optical module shell temperature obtained by using the optical module temperature monitoring and calibration method and device according to the embodiment of the present invention is within ±2° C., meeting the specification requirements.
[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims
1. An optical module temperature monitoring and calibration device, characterized in that: It includes a test optical module, a temperature monitoring device, a temperature calibration device, and a computer with GUI software installed; The temperature monitoring device includes a power chip, a temperature sensor chip and an MCU. The power chip is connected to the temperature sensor chip and the MCU to provide working voltage for the temperature sensor chip and the MCU. The temperature sensor chip is connected to the MCU. The output voltage of the temperature sensor chip changes with the temperature of the PCBA inside the test optical module. The MCU samples the output voltage of the temperature sensor chip in real time and calculates the PCBA monitoring temperature according to the output voltage and transmits it to the GUI software. The temperature calibration device includes a test circuit board, a temperature-adjustable sealed box and a spot thermometer. The spot thermometer is fixed on the tube shell of the test optical module and is used to test the case temperature of the optical module. The test optical module is inserted into the test circuit board and placed in the sealed box. The temperature calibration device also includes an analog optical module, an analog test circuit board and an optical fiber. The analog optical module is placed on the analog test circuit board. The test optical module and the analog optical module are connected through the optical fiber. After the analog optical module works normally, a PRBS code type is sent to the test optical module to provide a simulated normal working scene for the test optical module. The temperature in the sealed box is changed to make the case temperature of the tested optical module vary between 0℃ and 70℃. By comparing the case temperature of the optical module measured by the spot thermometer at different box temperatures and the PCBA temperature obtained by the GUI software, the temperature calibration coefficient and temperature compensation value of the linear relationship between the case temperature and the PCBA temperature of the optical module in the GUI software are adjusted. The GUI software obtains the case temperature of the optical module based on the PCBA monitoring temperature and the linear relationship between the case temperature and the PCBA temperature for reporting.
2. The optical module temperature monitoring and calibration device according to claim 1, characterized in that: The model of the power chip is ADP196, the model of the temperature sensor chip is LM94023BITM, and the model of the MCU is ADuC7023 or ADuCM320i.
3. The optical module temperature monitoring and calibration device according to claim 2, characterized in that: The 2V5 voltage output by the VREF pin of the MCU is used to provide the working voltage for the temperature sensor chip. The relationship between the output voltage V of the temperature sensor chip and the PCBA temperature T is as follows: V=-8.2(mV / ℃)*T(℃)+B Where V is the output voltage, T is the PCBA temperature, and B is a constant; The MCU calculates the PCBA monitoring temperature according to the output voltage using the above relationship.
4. The optical module temperature monitoring and calibration device according to claim 1, characterized in that: The temperature calibration device also includes a first switching power supply and a second switching power supply. The first switching power supply is connected to a test circuit board and a test optical module to provide a working voltage for the test circuit board and the test optical module. The second switching power supply is connected to an analog circuit board and an analog optical module to provide a working voltage for the analog circuit board and the analog optical module.
5. The optical module temperature monitoring and calibration device according to claim 1, characterized in that: The temperature-adjustable sealed box is a temperature-adjustable incubator.
6. The optical module temperature monitoring and calibration device according to claim 1, characterized in that: The temperature-adjustable sealed box is a wooden sealed box, and the temperature inside the wooden sealed box is changed by a rapid temperature shock box.
7. A method for monitoring and calibrating the temperature of an optical module, used in the device for monitoring and calibrating the temperature of an optical module according to any one of claims 1 to 6, characterized in that: The following steps are involved: Get the optical module PCBA temperature and case temperature under different ambient temperatures; Obtain the linear relationship between the optical module Case temperature and PCBA temperature according to the optical module PCBA temperature and Case temperature under different ambient temperatures; The temperature of the PCBA inside the optical module is monitored through the temperature sensor chip. The MCU calculates the PCBA monitoring temperature based on the output voltage of the temperature sensor chip that changes with the PCBA temperature. The optical module case temperature is obtained according to the optical module PCBA monitoring temperature and the linear relationship between the optical module case temperature and the PCBA temperature as the final optical module operating temperature report.
8. The optical module temperature monitoring and calibration method according to claim 7, characterized in that: The linear relationship formula between the optical module Case temperature and PCBA temperature is as follows: Temp=T*slope+offset Among them, Temp is the Case temperature, T is the PCBA temperature, slope is the temperature calibration coefficient, and offset is the temperature compensation value.