SPRiNG Technology
Solder-Free Connection
The SPRiNG Technology developed by Semikron Danfoss in the 1990s establishes connections between power modules and circuit boards via silver plated spring contacts instead of screw, solder, or press-fit contacts. Spring contacts are used both as control connections as well as for power connections within the context of the rapidly increasing current-carrying capacity of printed circuit boards.
Different spring types are used depending on the requirements. For auxiliary connections, Semikron Danfoss uses SPRiNG technology both in baseplate-less SKiiP modules as well as in SEMIX modules with baseplates to connect the driver board to the module.
Higher Shock and Vibration Resistance
MiniSKiiP modules use the same type of spring contact for power and auxiliary connections. Since the springs also have the task of pressing the DBC substrate to the heatsink (see description of SKiiP technology), these springs consist of significantly stronger material. If a temperature increase of 20K is allowed, the springs can carry approximately 20A. For more power, contact springs are connected in parallel within the module.
The main advantages of spring contacts over solder joints can be found in the higher shock and vibration resistance and temperature cycling capability due to the freely movable contacts. Stresses during operation, whether thermally or mechanically induced, are relieved by the movable contacts, so that a durable and reliable electrical connection is achieved.
SPRiNG technology is also advantageous for assembly, which can be done after soldering and preliminary testing of the printed circuit board. Investment and process costs are low since the completion of the final assembly requires neither soldering equipment nor elaborate installation aids such as press-in tooling. Spring contacts achieve a simple connection of module and circuit board and, if necessary, an equally easy removal.