In high-speed optical communication systems, optical transceiver plays a core role in converting electrical signals to optical signals. The emission wavelength of laser diode is highly sensitive to the junction temperature, turning temperature monitoring from an "auxiliary function" into a fundamental factor for link availability. EXSENSE optical transceiver gold termination NTC chip holds an irreplaceable position here due to its predictable resistance-to-temperature behavior and packaging compatibility.

Heat generated by the laser diode and driver IC inside the optical transceiver can shift the laser wavelength, which significantly degrades communication quality in long-distance links. Therefore, EXSENSE gold termination NTC chip is not an optional component but a prerequisite for wavelength stability. In typical optical module temperature control designs, NTC is usually mounted on the heat sink substrate where the laser (LD chip) is located, on the same plane as the LD chip to ensure quick and accurate junction temperature readings. The lower surface of the gold termination bare chip is connected to the heat sink using silver paste, and the upper surface is wire-bonded to the pin, ensuring good thermal and electrical coupling. In the solution adopting TEC, the heat sink substrate is fixed to the TEC, and the NTC is placed with the LD chip on top of the TEC. So how does the EXSENSE gold termination NTC chip benefit operation of optical transceiver when the laser diode junction temperature changes?

1. High Accuracy to Ensure Accurate Feedback for Temperature Control Loops

Temperature measurement deviations inside the optical transceiver affect the TEC loop control accuracy and the precision of over-temperature protection thresholds. The accuracy pf resistance value/Beta of EXSENSE gold termination NTC chip can reach ±1%, capturing tiny fluctuations in the laser diode junction temperature and providing reliable feedback signals to the TEC controller.

2. Excellent Sensitivity to Shorten Response Time

The NTC chip can respond in millisecond level, allowing temperature changes inside the optical transceiver to be quickly sensed and converted into detectable voltage signals. This shortens the response time of the temperature control system and effectively reduces feedback lag of the temperature feedback signal.

3. Small Dimension to Fit High-Density Packaging Trends

With the continuous development of CPO technology, available space inside optical transceiver is getting tighter. The size of EXSENSE gold termination NTC chip measures can reach 0.21mm × 0.21mm, saving installation space and allowing close placement to the LD chip on the limited heat sink area. This shortens the thermal path and reduces the delay of the temperature measurement signal.

As optical communication speeds upgrade from 100G to 800G, 1.6T, and application scenarios like DWDM and coherent communication demand stricter wavelength stability, precise temperature control of the laser diode determines the performance and reliability of optical transceiver. The addition of the EXSENSE gold termination NTC chip enhances temperature monitoring under dynamic working conditions, ensuring smooth operation of the optical transceiver.