Applications including e-scooters, e-forklifts and other LEVs, as well as power tools and battery management systems, necessitate high current rating, ruggedness and extended lifetime. Infineon Technologies AG answers these demands by providing more choices to power system designers to satisfy diverse design requirements and deliver maximum performance in the smallest space. With the innovative TO-Leadless (TOLL) package, it now offers two new OptiMOS power mosfet packages in the TOLx family: TOLG (TO-Leaded with Gullwing leads) and TOLT (TO-Leaded Top-side cooling). Together, the TOLx family provides very low RDS(on) and a high-current rating over 300A to increase system efficiency in high-power density designs.
The TOLG package blends the best features of TOLL and D 2PAK 7-pin packages, sharing the same 10mm x 11mm2 footprint and electrical performances as TOLL with added flexibility comparable to D 2PAK 7-pin. The main advantages of TOLG are especially apparent in designs with aluminium-insulated metal substrate boards. In these designs, the coefficient of thermal expansion, which illustrates the tendency of a material to change its shape in response to changes in temperature, is higher than copper-IMS and FR4 boards.
Over time, temperature cycling on board produces a crack in the solder joint between the package and the PCB. With the versatility of the gullwing leads, TOLG demonstrates superior solder joint robustness, noticeably improving product reliability in applications where repetitive temperature cycling takes place. The new package delivers two times higher TCoB performance compared to the IPC-9701 standard requirement.
The TOLT package is optimised for superior thermal performance. Constructed with its lead-frame flipped to position exposed metal on the top side, the package comprises multiple gullwing leads on each side for high current carrying drain and source connections. With a flipped lead-frame, heat passes from its exposed metal top side, through the insulating material, straight to the heatsink. Compared to the TOLL bottom-side cooling package, the TOLT improves R thJA, by 20% and R thJC by 50%. These specifications facilitate a lower BOM, especially for the heatsink. Furthermore, OptiMOS in TOLT decreases PCB space, as components may now be mounted on the bottom of the MOSFET.