Isabellenhütte unveils innovative PMx Pulse Load Resistors for enhanced voltage spike protection in automotive power electronics.
Isabellenhütte, a leading measurement specialist, announces the launch of its PMx series of pulse load resistors, specifically designed to absorb voltage spikes in power electronics for automotive applications.
These advanced resistors are engineered to protect downstream components from electrical overstress, ensuring the reliability and longevity of automotive systems.
Voltage spikes, often triggered by fast switching operations and amplified by inductances, pose a significant threat to downstream components, potentially causing damage or destruction. The PMx series, starting with the PMT (2817) size, offers a robust solution by safely dissipating these peaks. Utilizing Isabellenhütte’s proven SMD shunt technology, the PMx resistors are optimized for damping voltage spikes and pulse load rather than precision measurement.
ISA-PLAN® Design for Superior Performance
The PMT design adheres to the ISA-PLAN® principle, featuring a copper substrate with a foil made from Isabellenhütte’s proprietary Noventin® resistive material. This material’s high specific resistance enhances pulse load capacity, allowing voltage peaks to be temporarily stored and dissipated as heat through large copper terminals into the PCB. Depending on the pulse energy, multiple resistors can be configured in parallel or series arrays to evenly distribute the load, tailored to the expected pulse loads, available PCB space, and desired resistance values.
Application Example: Snubber Resistor for E-Fuse
In snubber circuits, particularly those used in E-Fuses for car cigarette lighter power supplies, PMx resistors excel. When excessive current is drawn, the E-Fuse disconnects to protect connected devices, activating the snubber circuit. The capacitor absorbs the pulse load and discharges through the pulse load resistor, converting energy into heat and dissipating it via copper terminals into the PCB.
Meeting Automotive Reliability Standards
All PMx series resistors undergo rigorous testing in accordance with the AEC-Q200 automotive standard. The PMT is currently available in size 2817 with a value range from 50 mOhm to 2.5 Ohm (R050, R500, 1R00, and 2R50). It is in the final phase of the qualification process, with series production (SOP) scheduled to commence at the end of March 2026. Customer-specific variants can be realized within this range, and additional sizes, such as the PMS in 2512 and the PMP in size 2010, are available upon request. Samples are available for evaluation.
Comprehensive Technical Support
Isabellenhütte offers seamless integration of PMx pulse load resistors into PCB designs. For higher pulse loads, the company provides expert support in selecting the appropriate number and type of resistors, as well as in dimensioning, configuration, and design-in. Thermal simulations can be performed upon request to assess heat development and dissipation.
Key Benefits of PMx Pulse Load Resistors:
- High pulse load capacity throughout product lifetime and rapid heat dissipation
- Space-saving design, eliminating bulky, manually mounted THT components
- Array configuration for high pulse energies and customized dimensioning
- Efficient SMD mounting (tape-on-reel)
- Comprehensive support with selection, dimensioning, and design-in