As an important part of optical fiber communication,optical module can ensure the normal operation of optical network only by ensuring its stable operation.
The operating temperature has a great impact on the use of the optical module.If the operating temperature of the optical module is too high or too low,the optical power will generally decline,the sensitivity will become lower,and the eye diagram will become worse.In addition,it will also accelerate the aging of internal devices,reduce the life of the optical module,and even directly damage the optical devices in serious cases.
Generally,when the operating temperature of the optical module increases,the optical power will decrease,and the APC(optical power automatic control circuit)will maintain the stability of the optical power of the optical module.However,if the temperature continues to rise,the APC will lose control,and the bias current will increase sharply.If the monitoring value is exceeded,it will automatically lock up,and eventually the driver chip or TOSA will be burned.
The operating temperature specifications of optical modules are divided into commercial grade(0-70℃),expansion grade(-20-85℃)and industrial grade(-40-85℃),but the most widely used temperature ranges are commercial grade and industrial grade.
We should choose the working temperature of the optical module according to the actual use environment.If it is applied in the data center and enterprise computer room,we can use commercial optical modules,because the data center and computer room will be equipped with air conditioners to maintain the stability of the indoor temperature.If it is used in outdoor,remote mountain,tunnel and other environments with large temperature changes,industrial optical modules need to be used.Industrial optical modules will import temperature compensation software,which is used to ensure that the optical modules have a stable working current supply.When the temperature changes,the temperature compensation software will work.
The current optical modules can support the DDM function,monitor the temperature,transmitted optical power,received optical power,current,voltage and other parameters of the optical module,as well as temperature compensation.
If it is not within the normal range,DDM alarm will appear.Each optical module has a temperature compensation function.The temperature compensation is automatically controlled by the APC circuit and will change with the temperature change.Generally,the commercial optical module will not have excessive temperature under the working environment of 0-70℃.If the temperature is too high,DDM alarm will appear.
Finally,when selecting optical modules,we must pay attention to selecting the corresponding level of optical modules according to the use environment,so as to ensure the stable operation of optical modules.
