With the development of optical communication technology, BOSA (Bi-Directional Optical Sub-Assembly) as one of the core components of optical network terminal, its performance directly affects the stability and reliability of the entire terminal system. Since BOSA is particularly sensitive to temperature and its electrical characteristics are significantly different at different temperatures, the NTC chip can effectively realize the accurate monitoring and control of the internal temperature of BOSA, so as to improve the calibration accuracy and performance of optical network terminal.

In general, NTC chips are installed in TOSA and ROSA in BOSA. Its lower surface will be assembled on the substrate by soldering process, and the upper surface will be connected to the pins of TOSA and ROSA by bonding process. The NTC is electrically connected to BOSA's microcontrol unit (MCU) and temperature monitoring unit via pins. Specifically:

First, when BOSA is running, the NTC chip will start to measure the temperature in real time. When the temperature changes, the resistance value of the NTC also changes; This data will be transmitted to the MCU for temperature calculation through the temperature monitoring unit, so as to realize the operating temperature monitoring of BOSA.

Second, when the NTC chip completes the temperature acquisition, the MCU will adjust the relevant parameters according to the obtained data to keep the internal temperature of the BOSA within a suitable range. For example, when the temperature is detected to be too high, the MCU can reduce the driving current, lower power consumption, so that the temperature is brought down to normal range; On the contrary, when the temperature is too low, the driving current can be appropriately increased to increase the operating temperature.

BOSA ensures optimal operation with the help of NTC chips and other components. In order to cooperate with BOSA to improve the integration, EXSENSE Electronics Technology Co., Ltd. independently developed and mass-produced a small-size gold electrode NTC chip for optical communication, with a size of 0.25mm × 0.25mm, this NTC:

First, the small size has higher sensitivity and can respond quickly when the BOSA operating temperature changes. This is very important for real-time monitoring and control of the internal temperature of BOSA, especially in high or low temperature environments, so that the MCU can take timely measures to avoid damage to BOSA caused by too high or too low temperature;

Second, the high accuracy of the gold electrode bare chip can provide accurate temperature measurement when BOSA is in an extreme temperature environment, helping BOSA accurately monitor the internal temperature and improve the temperature control accuracy of the system.

Third, the gold electrode NTC has excellent consistency and is not easily affected by environmental factors, which can assist BOSA to maintain high reliability and reduce maintenance costs during long-term operation.

In summary, it is of great significance to use the gold electrode NTC chip for optical communication to monitor and control the internal temperature of BOSA to improve its calibration accuracy and performance. The addition of gold electrode NTC chip not only contributes to the temperature acquisition efficiency of BOSA, but also provides a guarantee for the first-pass yield rate of optical network terminal.