Compensation device for expanding CWDM wavelength low-temperature working point

Abstract

The utility model provides a compensation device for expanding a CWDM wavelength low-temperature working point, which can expand an application environment of a CWDM optical module to an industrial grade, ensure stable working and is low in cost. The compensation device comprises a laser, a control module and an adjusting module. Wherein a heating resistor and a thermistor are integrated in the laser; the control module is connected with the laser and the adjusting module and is used for outputting a corresponding signal to the adjusting module according to the working temperature of the laser sensed by the thermistor; and the adjusting module is used for outputting a corresponding current signal to the heating resistor according to the signal output by the control module so as to carry out heating adjustment on the laser.

Description

Technical Field

[0001] The utility model relates to the technical field of optical communication, and particularly relates to a compensation device for expanding the low-temperature working point of CWDM wavelengths. Background Art

[0002] CWDM (Coarse Wavelength Division Multiplexer) is a low-cost WDM transmission technology for the access layer of metropolitan area networks. The working wavelength range of CWDM optical modules is within ±6.5 nm of the central wavelength, and the full-temperature drift is ≤13 nm. The CWDM modulation lasers of optical modules use uncooled lasers, which use electronic tuning, and their central wavelength will change with temperature rise or fall. That is, when the temperature changes by 10 degrees, the wavelength will change by 1 nm. For CWDM optical modules directly using uncooled lasers, their application environment is relatively harsh and can only work at commercial-grade temperatures, that is, satisfy the application at -20 to 85 degrees. However, when working at industrial grade (-40 degrees), the wavelength drift will cause the central wavelength to exceed the ±6.5 nm range starting from -20 degrees, which will make the CWDM system work unstably and cause a series of problems such as communication error codes. To solve the above problems, currently, a TEC temperature controller is directly used for temperature control, but this method has a relatively high cost. Content of the Utility Model

[0003] In view of the above problems, the utility model provides a compensation device for expanding the low-temperature working point of CWDM wavelengths, which can expand the application environment of CWDM optical modules to industrial grade, ensure stable operation, and has a low cost.

[0004] The utility model adopts the following technical scheme: A compensation device for expanding the low-temperature working point of CWDM wavelengths includes a laser, a control module, and an adjustment module. Among them, a heating resistor and a thermistor are integrated in the laser.

[0005] The control module is connected to both the laser and the adjustment module, and is used to output a corresponding signal to the adjustment module according to the working temperature of the laser sensed by the thermistor.

[0006] The adjustment module is used to output a corresponding current signal to the heating resistor according to the signal output by the control module to adjust the heating of the laser.

[0007] Further, the control module includes a controller U1, a resistor R1, and capacitors C1 to C6. The controller U1 uses a control chip of model GD32E232E6U7. One end of the capacitor C1 is connected to one end of the resistor R1 and the 2nd pin of the controller U1. The other end of the capacitor C1 is grounded. The other end of the resistor R1 is connected to the power supply voltage VCCD. One end of the capacitor C6 is connected to the 15th pin of the controller U1 and then grounded. The other end of the capacitor C6 is connected to the 16th pin of the controller U1. One ends of the capacitors C2 and C3 are connected to the 3rd pin of the controller U1 and then grounded. The other ends of the capacitors C2 and C3 are connected to the 4th pin of the controller U1. One ends of the capacitors C4 and C5 are connected to the 5th pin of the controller U1 and then connected to the power supply voltage VCCD. The other ends of the capacitors C4 and C5 are connected to each other and then grounded.

[0008] Further, the adjustment module includes an operational amplifier U2, resistors R2 to R5, and a capacitor C7. The operational amplifier U2 uses a chip of model SGM8604-3. One end of the resistor R2 is connected to the 1st pin of the operational amplifier U2 and then connected to the 12th pin of the controller U1. The other end of the resistor R2 is grounded. One end of the resistor R3 is connected to the 2nd pin of the operational amplifier U2 and then grounded. The other end of the resistor R3 is connected to one end of the resistor R4, one end of the capacitor C7, and the 3rd pin of the operational amplifier U2. The other end of the resistor R4 is connected to the other end of the capacitor C7 and the 4th pin of the operational amplifier U2. One end of the capacitor C8 is connected to the 6th pin of the operational amplifier U2. The other end of the capacitor C8 is connected to one end of the resistor R5 and then grounded. The other end of the resistor R5 is connected to the 5th pin of the operational amplifier U2 and then connected to the 14th pin of the controller U1.

[0009] Further, the laser includes a laser chip U3. The laser chip U3 uses a chip of model TOSA-FPC. The heating resistor is connected between the 3rd and 4th pins of the laser chip U3. The 2nd pin of the laser chip U3 is used to connect the thermistor. And the 2nd pin of the laser chip U3 is connected to one end of the resistor R6 and then connected to the 22nd pin of the controller U1. The other end of the resistor R6 is connected to the 4th pin of the controller U1. The 3rd pin of the laser chip U3 is connected to the 4th pin of the operational amplifier U2. The 4th and 7th pins of the laser chip U3 are both grounded.

[0010] The beneficial effects of the present utility model are as follows. At different temperatures, the thermistor can sense different operating temperatures of the laser. The control module enables the control and adjustment module according to the operating temperature of the laser, so as to heat the laser correspondingly through the heating resistor. Then, the wavelength of the laser will no longer continue to change as the ambient temperature decreases. It can extend the laser with CWDM wavelength from the commercial operating temperature to the industrial operating temperature, and the cost is also lower than that of the TEC temperature control method, having better economic value in use. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is the structural block diagram of the present utility model;

[0012] Figure 2 is the circuit schematic diagram of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0013] As Figure 1 、 Figure 2 shown, a compensation device for expanding the low-temperature operating point of the CWDM wavelength of the present utility model includes a laser, a control module, and an adjustment module. Among them, a heating resistor and a thermistor are integrated in the laser. The control module is connected to both the laser and the adjustment module, and is used to output a corresponding signal to the adjustment module according to the operating temperature of the laser sensed by the thermistor. The adjustment module is used to output a corresponding current signal to the heating resistor to heat and adjust the laser according to the signal output by the control module.

[0014] The control module includes a controller U1, a resistor R1, and capacitors C1 to C6. The controller U1 uses a control chip of model GD32E232E6U7. One end of the capacitor C1 is connected to one end of the resistor R1 and the 2nd pin of the controller U1. The other end of the capacitor C1 is grounded. The other end of the resistor R1 is connected to the supply voltage VCCD (3.3V). One end of the capacitor C6 is connected to the 15th pin of the controller U1 and then grounded. The other end of the capacitor C6 is connected to the 16th pin of the controller U1. One ends of the capacitors C2 and C3 are connected to the 3rd pin of the controller U1 and then grounded. The other ends of the capacitors C2 and C3 are connected to the 4th pin of the controller U1. One ends of the capacitors C4 and C5 are connected to the 5th pin of the controller U1 and then connected to the supply voltage VCCD. The other ends of the capacitors C4 and C5 are connected and then grounded.

[0015] The adjustment module includes an operational amplifier U2, resistors R2 to R5, and a capacitor C7. The operational amplifier U2 uses a chip of model SGM8604-3. One end of the resistor R2 is connected to the pin 1 of the operational amplifier U2 and then connected to the pin 12 of the controller U1, and the other end of the resistor R2 is grounded. One end of the resistor R3 is connected to the pin 2 of the operational amplifier U2 and then grounded, and the other end of the resistor R3 is connected to one end of the resistor R4, one end of the capacitor C7, and the pin 3 of the operational amplifier U2. The other end of the resistor R4 is connected to the other end of the capacitor C7 and the pin 4 of the operational amplifier U2. One end of the capacitor C8 is connected to the pin 6 of the operational amplifier U2, and the other end of the capacitor C8 is connected to one end of the resistor R5 and then grounded. The other end of the resistor R5 is connected to the pin 5 of the operational amplifier U2 and then connected to the pin 14 of the controller U1.

[0016] The laser includes a laser chip U3. That is to say, a laser chip U3, a heating resistor, and a thermistor are integrated in the laser. The laser chip U3 uses an existing model TOSA-FPC chip. The heating resistor is connected between the pins 3 and 4 of the laser chip U3. The pin 2 of the laser chip U3 is used to connect the thermistor, and the pin 2 of the laser chip U3 is connected to one end of the resistor R6 and then connected to the pin 22 of the controller U1. The other end of the resistor R6 is connected to the pin 4 of the controller U1. The pin 3 of the laser chip U3 is connected to the pin 4 of the operational amplifier U2. The pins 4 and 7 of the laser chip U3 are both grounded.

[0017] A compensation method for expanding the low-temperature operating point of CWDM wavelengths includes:

[0018] Sensing the operating temperature of the laser through a thermistor and feeding back the sensed operating temperature of the laser to the control module;

[0019] The control module compares the received operating temperature with a threshold temperature and outputs a corresponding signal to the adjustment module according to the comparison result;

[0020] The adjustment module outputs a current of a corresponding magnitude to the heating resistor according to the received signal to heat the laser through the heating resistor so that the operating wavelength of the laser meets the central wavelength range;

[0021] Specifically, if the operating temperature of the laser is greater than the threshold temperature, a stop signal is output to the adjustment module to control the heating resistor to stop heating the laser;

[0022] If the operating temperature of the laser is less than the threshold temperature, a heating signal is output to the adjustment module. Subsequently, the adjustment module outputs a current of a corresponding magnitude to the heating resistor to heat the temperature of the laser to the threshold temperature through the heating resistor.

[0023] This utility model enables the laser with CWDM wavelength to extend its operating temperature from the commercial working temperature to the industrial working temperature (-40°C). It has low cost, controls the heating resistor to heat the laser, and the operating wavelength of the laser meets within ±6.5 nm of the central wavelength.

[0024] The working principle of this utility model is that at low temperature, it monitors the operating temperature of the laser through a thermistor. That is, at different temperatures, the resistance value of the thermistor is different, and the THER_MON terminal will output the corresponding voltage to the controller U1. Once the operating temperature of the laser is lower than the threshold temperature, the controller U1 enables the operational amplifier U2 to provide an adjustable current to the heating resistor. Subsequently, the heating resistor generates heat, thereby changing the operating temperature of the laser in the low-temperature environment until the operating wavelength of the laser meets within ±6.5 nm of the central wavelength, at which point the heating resistor stops heating the laser, thus achieving that the laser wavelength no longer changes continuously with the decrease of the ambient temperature and ensuring the working stability.

[0025] Figure 2 In it, LD Anode represents the positive electrode of the laser, and LD Cathode represents the negative electrode of the laser;

[0026] Thermintor: As the access terminal for the thermistor; the thermistor is not shown in the figure;

[0027] The thermistor and the resistor R6 divide the voltage of VREF, and the THER_MON terminal outputs the voltage value to the controller U1 to realize the feedback of the operating temperature of the laser, that is, the controller U1 obtains the operating temperature of the laser by collecting the ADC value;

[0028] HEAT: As the input terminal for the heating current;

[0029] TEC_EN: As the enable terminal to enable the operation of the operational amplifier U2;

[0030] CTL_DAC: Outputs different voltages through the controller U1 to generate a DAC to control the magnitude of the heating current at the CTL_DAC terminal, and outputs the heating current through the operational amplifier U2;

[0031] VREF: As the reference voltage of 2.4 V;

[0032] HEAT RESISTOR: Represents the heating resistor.

[0033] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above-described exemplary embodiments, and the present utility model can be implemented in other specific forms without departing from the spirit or basic characteristics of the present utility model. Therefore, in any aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present utility model. Any reference signs in the claims should not be construed as limiting the claims involved.

[0034] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A compensation device for extending the low temperature working point of CWDM wavelength, characterized in that: It includes a laser, a control module and an adjustment module; wherein a heating resistor and a thermistor are integrated in the laser; The control module is connected to the laser and the adjustment module, and is used to output a corresponding signal to the adjustment module according to the working temperature of the laser sensed by the thermistor; The regulating module is used to output a corresponding current signal to the heating resistor according to the signal output by the control module to perform heating regulation on the laser.

2. A compensation device for extending the low temperature working point of CWDM wavelength according to claim 1, characterized in that: The control module includes a controller U1, a resistor R1, and capacitors C1 to C6. The controller U1 adopts a model GD32E232E6U7 control chip; one end of the capacitor C1 is connected to one end of the resistor R1 and pin 2 of the controller U1, the other end of the capacitor C1 is grounded, the other end of the resistor R1 is connected to a power supply voltage VCCD, one end of the capacitor C6 is connected to pin 15 of the controller U1 and then to ground, the other end of the capacitor C6 is connected to pin 16 of the controller U1, one end of the capacitors C2 and C3 is connected to pin 3 of the controller U1 and then to ground, the other end of the capacitors C2 and C3 is connected to pin 4 of the controller U1, one end of the capacitors C4 and C5 is connected to pin 5 of the controller U1 and then to a power supply voltage VCCD, and the other ends of the capacitors C4 and C5 are connected and then to ground.

3. A compensation device for extending the low temperature working point of CWDM wavelength according to claim 2, characterized in that: The regulating module includes an operational amplifier U2, resistors R2 to R5, and a capacitor C7. The operational amplifier U2 adopts a chip model SGM8604-3; one end of the resistor R2 is connected to pin 1 of the operational amplifier U2 and then connected to pin 12 of the controller U1, the other end of the resistor R2 is grounded, one end of the resistor R3 is connected to pin 2 of the operational amplifier U2 and then connected to ground, the other end of the resistor R3 is connected to one end of the resistor R4, one end of the capacitor C7, and pin 3 of the operational amplifier U2, the other end of the resistor R4 is connected to the other end of the capacitor C7 and pin 4 of the operational amplifier U2, one end of the capacitor C8 is connected to pin 6 of the operational amplifier U2, the other end of the capacitor C8 is connected to one end of the resistor R5 and then connected to ground, and the other end of the resistor R5 is connected to pin 5 of the operational amplifier U2 and then connected to pin 14 of the controller U1.

4. A compensation device for extending the low temperature working point of CWDM wavelength according to claim 3, characterized in that: The laser includes a laser chip U3, which adopts a TOSA-FPC chip model. The heating resistor is connected between pins 3 and 4 of the laser chip U3. Pin 2 of the laser chip U3 is used to connect the thermistor, and pin 2 of the laser chip U3 is connected to one end of a resistor R6 and then connected to pin 22 of the controller U1. The other end of the resistor R6 is connected to pin 4 of the controller U1, pin 3 of the laser chip U3 is connected to pin 4 of the operational amplifier U2, and pins 4 and 7 of the laser chip U3 are both grounded.

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