BOSA (Bi-Directional Optical Sub-Assembly) can complete optical-electrical/electrical-optical bidirectional conversion within the module, which meets the highly integrated needs of today's optical communication system, so it is favored by more and more optical communication manufacturers. However, the working stability of BOSA is highly dependent on temperature, even slight temperature fluctuations will affect its transmitting power and receiving sensitivity. Therefore, NTC chip is required to cooperate with temperature monitoring to ensure the stable operation of BOSA.

The NTC chip is generally installed on the BOSA die substrate and connected to its temperature monitoring module, which directly reflects the internal temperature change of BOSA and effectively reduces the deviation of temperature acquisition. Specifically, the lower surface of the NTC is set on the substrate through soldering process (e.g., silver paste); The upper surface is electrically connected to the die pin through bonding processes (e.g. gold wire), and is connected to BOSA's control module, signal amplifier and temperature monitoring module via pins. When the NTC chip collects the temperature signal, it will be converted into a voltage signal, then compared with the preset voltage value. The voltage difference obtained from the comparison is amplified by the signal amplifier and transmitted to the control module to complete the entire temperature acquisition process. In terms of selection, EXSENSE Electronics recommends the use of DT-G series gold termination NTC chip:

1. High accuracy, the addition of gold termination NTC can effectively improve the accuracy of BOSA temperature monitoring, assist it in reducing the error of temperature correction, ensure the accuracy and reliability of temperature data collection of the control module, and improve the first-pass yield of BOB (BOSA on Board) calibration.

2. Small dimension, gold termination NTC chip can reach 0.25mm × 0.25mm, which can meet the integration need of BOSA and save more installation space for its internal compact space.

3. Excellent sensitivity, gold termination bare chip of EXSENSE Electronics has excellent consistency, which makes its response speed faster than that of traditional NTC chips and reducing the time consumption of the temperature monitoring process, avoids wavelength drift and reception sensitivity degradation caused by instantaneous temperature rise, and reduces the bit error rate of high-speed transmission.

In summary, the efficient temperature monitoring of the gold termination NTC chip solves the core pain point of BOSA being sensitive to temperature, and realizes the real-time collection and feedback of temperature data. With the update and iteration of optical transceiver, EXSENSE Electronics' high-accuracy gold termination NTC chip is moving from "temperature sensing component" to "temperature monitoring pivot", assisting BOSA in diagnosing the internal temperature status in real time and improving its temperature management system.