HSMtec®

In the HSMtec® process, 500 µm thick copper elements with variable widths of 2 to 12 mm and individual lengths are placed in the inner layers of the multilayer and embedded in the PCB. By partially integrating copper profiles into the PCB, high-current paths - or thermal management and fine conductor layout - can be easily combined and adapted to the spatial conditions. As the copper profiles are partially integrated into the PCB, load and logic or power and control electronics can be combined on one PCB.

The copper elements are connected to the etched inner and/or outer layers using ultrasonic bonding technology. The integrated copper elements transmit currents of up to 400 A and also quickly reduce heat generation to permissible partial and system temperatures. This enables simple integration into a standard multilayer production process with subsequent pressing of the individual layers. Thanks to a large number of design variants, high currents and power losses of components can be fed into PCBs in a targeted manner - without any further external work steps.

Power components and control electronics on one board

HSMtec® PCB technology combines load and logic on one assembly with a minimum PCB surface area. This makes it possible to meet the electrical specifications for dielectric strength and insulation classes in automation as well as demanding temperature conditions with limited installation space in automotive electronics.

A look at the specific thermal conductivity shows the importance of the continuous metallic path from the source to the sink and the potential of HSMtec®. Copper conducts heat 1000 times better than FR4. The intelligent combination of integrated copper profiles with Thermovias makes it possible to connect the power components directly to the copper profiles and avoid bottlenecks in the heat path.

A thermally optimized layer structure also ensures rapid heat dissipation and supports the overall thermal concept. A practical example shows this clearly: the current carrying capacity of a conductor track can be doubled if there are two inner ground layers underneath that have no self-heating. Another example shows the potential of Thermovias: more than 400 plated-through holes with a diameter of 0.25 mm can be placed on an area of 10 mm x 10 mm, so that the area then consists of 10 % of copper.

The effective thermal conductivity of such an FR4 surface is increased to 30 W/m-K by this design measure. This means that this construction is a hundred times more thermally conductive than FR4 and even ten times more conductive than the best heat conducting substrates. HSMtec® has been qualified by independent testing institutes and uses standard FR4 material. It is also manufactured using the standard production process and can be further processed in the usual assembly and soldering process.

The connection technology: highly current-optimized and compact

The PCB connection components from Weidmüller's Omnimate Power range complement the HSMtec® PCB. The PCB terminal blocks designed for servo controllers and frequency converters are available with a pitch of up to 15 mm and a power range of up to 150 A/1000 V (IEC) or 127 A/600 V (UL) and in various contact types. HSMtec® PCBs are also contacted with screw and pressure contacts especially for IGBTs, press-fit contacts in compliance with the required press-fit tolerances and with solder contacts for through-hole technology (THT) or with reflow-capable components for automated SMT processes.