In the case of fast switching operations in power electronics, such as in the automotive sector, voltage peaks can cause inductances and damage or destroy sensitive downstream components in the circuit. An RC snubber shunt can dampen voltage peaks by dissipating excess energy outwards. Isabellenhütte has developed a low-ohmic snubber shunt, SMT-V, which has a particularly high pulse power rating.
The SMT-V developed by Isabellenhütte has a low resistance value at 17.5 mOhm and a very compact design. It is based on the existing current measuring resistor SMT, which has large Cu legs for excellent heat dissipation from components and already has a high pulse power rating and long-term stability. The design and material of the new SMT-V were adapted to withstand this particular pulse load better. The development arose from a customer request because no adequate standard component with this resistance value was available on the market.
The special feature of this snubber shunt compared to other shunt series from Isabellenhütte is that it is not used for current measurement but is intended specifically to absorb high pulse loads. The high pulse power rating is achieved by using the proprietary material NOVENTIN®, which has a specific resistance nearly twice as high as MANGANIN® used in current measuring resistors.
The SMT-V can absorb an energy pulse of 2.5 J at a pulse duration of 0.1 s at a terminal temperature of 120 °C and up to 50 pulses over the life cycle with a corresponding gap time. This corresponds to a power loss per pulse of 25 W.
wire / Hall 11 / B31
