Active Cooling of Optical Transceivers

Tier 1 OEMs in telecom infrastructure market are designing the next standard for telecommunications, 5G. Compared to current LTE (4G) systems it will provide faster data transmission speeds. The latency will be significantly lower, reducing the number of times packets need to be resent. This will be a benefit for mobile users in densely populated areas trying to stream movies, music or live TV on their smart devices.

Faster communications mean thermal challenges

Faster data communications will present challenges for critical components such as optical transceivers. They are installed in radio units to transmit and receive data from the base station. The temperature of the device for outdoor environment will increase due to smaller form factors and no access to forced airflow, which will increase the heat flux density of the radio unit. Since this results in high temperatures exceeding the maximum operating limit of the optical transceiver, an active cooling solution is required.

An optical transceiver is a small form factor (SFP) pluggable transceiver. The transceiver contains a laser diode that transmits data, and the ability to assure transmission of data depends on keeping the temperature typically below 70°C. The traditional thermal solution for the SFP is currently passive, containing an interface material attached to a heat sink that dissipates heat through natural convection. This option, however, has been found to have difficulty with rejecting heat into ambient environment for radio units in 5G systems.

Laird Thermal Systems’ ATC thermoelectric assembly

The Active Transceiver Cooler (ATC) is specifically designed for small form-factor pluggable (SFP) transceivers. The ATC thermoelectric assembly consists of a custom thermoelectric module (TEM), an aluminum base, Tflex thermal gap fillers, an NTC thermistor, fastener clips and connector. Featuring a Coefficient of Performance (COP) rating above 1.0 without forced airflow, the customizable thermoelectric modules offer a highly reliable thermal solution built to operate in high temperature environments. Additionally, the ATC requires no maintenance and can cool hot spots below surrounding ambient conditions using the thermoelectric module.

Laird Thermal Systems’ ATCTM line of miniature form factor thermoelectric assemblies provides the size and the cooling accuracy required to obtain peak performance for SFPs under the more demanding data transmission requirements of upcoming 5G networks. It is the optimal solution to maintain form factor and minimize latency of a remote radio unit.

Key System Features

  • Maintaining a high Coefficient of Performance (COP) to limit heat rejection requirements from TEM onto natural convective heat sink.
  • Durable construction to operate in elevated temperature environments, up to 120°C.
  • No maintenance

Laird Thermal Systems' ATCTM series is a unique solution. Learn more about its features in our application note Active Cooling of Optical Transceivers