1、Zero-Bias TLVR Exploration for Future Datacenter Computing ApplicationsGoogle Zero-Bias TLVR Exploration for Future Datacenter Computing ApplicationsRACK&POWERPresenters:Chi Hsu,Senior Power Engineer,GoogleContributors:Walter Lai,Gregory Sizikov,and Steven Cheng GoogleSimon Ko,Global Commodity Manag
2、er,GoogleAlan Deng,Global Commodity Manager,GoogleBackground Trans-Inductor Voltage Regulator(TLVR)Technology is a new onboard xPU power delivery solution proposed by Google in IEEE APEC 2020.TLVR is an innovative fast-transient onboard voltage regulator(VR)solution for xPUs.This VR topology provide
3、s increased VR bandwidth,faster transient response,and potential reduction in decoupling capacitors.TLVR has been widely used in recent years since it offers a good transient performance with reduced equivalent output transient inductance.However,existing TLVR has not been optimized for power effici
4、ency and density.One of the limitations is that each trans-inductor has to be designed for the peak load current in terms of magnetic core saturation.ZB-TLVR TopologyDC bias flux density in all of the TLVR inductors remains zero when the primary and secondary winding currents are balanced.This enabl
5、es much higher magnetic core utilization with the significantly reduced Isat requirement.If keeping the inductor size unchanged,Lm can be significantly increased to reduce the inductor current ripples for higher power efficiency.Design Challenge-DCR issueUsing conventional way for TLVR secondary win
6、ding interconnections results in much higher DCR loss.More innovative TLVR inductor structures are needed to reduce the secondary winding DCR and PCB interconnection power losses.Design Proposal-Group TLDesign Proposal-MagneticTLVR secondary winding and PCB interconnection DCRs are significantly red