Webinar: Benefits & Advantages of GaN in a Data Center PSU

In This Webinar You’ll Learn:

  • The Economic and Sustainability value of GaN in Power Supply Units
  • GaN’s technical advantages in Power Factor Correction and LLC Resonant Converter topologies
  • How to take advantage of GaN Systems’ Next Generation Power Stages in 3 key areas:
    • Thermal Performance
    • Switching Performance
    • Efficiency Improvement

Questions & Answers

Data Center PSUs get tested to industry standard performance requirements. One of the criteria is efficiency. A 94% efficiency at 50% load is named Platinum. A 96% measured efficiency at 50% load is call Titanium. The industry has shifted to requiring Titanium or even Titanium plus efficiency levels, meaning higher then 96% efficiency at 50% load.

Absolutely, this is one of the advantages of the CerStrate Power Stage design. The cost adder of the CerStrate power stage PCB is minor when considering the total system BOM cost. When considering the system cost, CerStrate can actually help to reduce the total BOM cost when things such as heatsink size, and manufacturability are taken into account.

Negative gate bias is not required but can be implemented depending on factors such as layout, dV/dt, power level and desired design margin. Generally we recommend a 2-3 volt negative gate bias voltage for turn off for hard-switched topologies in the 3kW range to eliminate any risk of false turn-on. Refer to our Application Note GN012 for specific recommendations.

We are seeing designs with GaN in the power shelf power supplies and in the Battery Backup Unit (BBU). We cannot comment on certification, that is the responsibility of the system manufacturer.

We do not see any issues with the 20ms hold-up time requirement. The power switch is not usually the bottleneck. Using GS66508B as an example, the peak current capability is 60A, which is sufficient for 3kW data center applications.

GaN not only provides a much lower switching loss but also enables the use of the totem pole PFC topology, which has better magnetic and semiconductor utilization. GaN provides a significant advantage for increasing the power density of the power converter along with increasing efficiency.

Interleaving is a great method to reach higher power and higher power density for power converters. The interleaved two-phase topology can cancel each other’s noise and current ripple to reduce the EMI filter and magnetics components size. However, there is a bit of a cost premium for interleaving drivers, aux power supplies, and a more powerful controller. So, there is a trade-off, and the decision is case by case depending on design objectives.

Although CRM control can achieve ZVS to reduce switching loss and hard switching noise, when the power is higher than 1kW, the peak current for CRM will be somewhat challenging to handle. So, in general, CCM is preferred.

Yes, visit our website for our 3kW PFC and LLC reference designs. The IMS boards are also available on our website. You can review details on the “Evaluation Kits & Reference Designs” section in “Design Center” pulldown area of our website. You can purchase them from our distributors.

Yes, we offer comprehensive engineering support to our customers for transformer design and passives selection. Please contact your local sales representative for more information.

Download the Presentation from this Webinar

    Moderator: Paul Wiener

    VP Strategic Marketing at GaN Systems

    Paul Wiener is GaN Systems’ Vice President of Strategic Marketing. Prior to joining GaN Systems, Paul led the power magnetics business unit at Eaton. Paul brings more than 25 years’ experience in operations, sales and marketing, and business development. His experience includes vice president of sales at Fultec Semiconductor Inc. and several management roles at Genoa, BroadLogic, and Raychem.