Industry White Papers

TO-LL and MDmesh M6: The Latest Breakthrough in High-Level Telecom SMPS

August 31, 2020 by STMicroelectronics

This paper presents the ST’s new SMD package TO-LL (TO-LeadLess) and its benefits in terms of thermal management, PCB area, switching performance, and parasitic inductance on the leads.

Nowadays, the demand for more efficient and compact switch-mode-power-supplies (SMPS) for telecom and server applications is increasing. The combined trends of continuous reduction in the volume and size of power converters and the increase in the required output power represent challenging issues in modern SMPS designs.

When addressing the high-power density requirement, even in an SMPS with high peak efficiency, a typical problem is the heat generated in the limited available volume, especially at full load. For this reason, SMD packages are substituting the classic through-hole packages in order to reduce occupied space on PCB, but the high-power demands of typical telecom SMPS (1.5 kW for half-bridge or 3 kW for full-bridge) and the need for appropriate thermal dissipation calls for new and improved SMD packages, such as the TOLL.