Fault currents are detected and shut down within a few microseconds. This significantly reduces the short-circuit energy in the system.
Electronic fuses (E-fuses) offer a new approach to protecting 12V, 48V, and high-voltage vehicle electrical systems. By using intelligent power semiconductors, they detect fault currents in real time, limit short-circuit energy, and enable significantly faster shutdown than conventional protection concepts like pyrofuses.
At the same time, E-fuses integrate measurement, diagnostic, and monitoring functions for current and voltage. This allows protective functions to be tailored more closely to the vehicle’s actual operating conditions and enables vehicle architectures to be designed more efficiently.
Preh develops electronic fuses for 400V and 800V battery systems. The technology is particularly well-suited for charging paths, battery disconnect units, power distribution units, and other safety-critical high-voltage applications.
Highlights
For low-voltage applications, Preh offers smart electronic fuses to supplement or replace traditional melting fuses.
Applications
Features
Faster shutdown
Fault currents are detected and shut down within a few microseconds. This significantly reduces the short-circuit energy in the system.
Integrated Diagnostics
Continuous monitoring of current, voltage, and system status provides maximum transparency into the vehicle electrical system.
Resettable Protection Function
Different to pyrofuses, E-fuses can be reactivated after certain fault events.
Optimized System Costs
Reduced requirements for downstream components enable more compact and cost-effective vehicle architectures.
| Criterion | E-Fuse | Pyrofuse |
| Shutdown Times | < 5µs | approx. 2ms |
| Reusability | Yes | No |
| Diagnostic Functions | Integrated | External diagnostics required |
| Triggering | Automatic | via BMS |
| Maintenance | Low | Replacement required |
| Technology | Semiconductor-based | Pyrotechnic |
The current and voltage measurement, diagnostic, and monitoring functions integrated into the e-fuse enable it to take over key tasks of the battery management system. This allows functions to be consolidated, control unit architectures to be simplified, and transparency regarding the battery’s status to be increased.
In order to offer our customers tailor-made solutions, we have a variety of cooperation models:
Includes complete development including system design, hardware, software and mechanical design. We develop according to the latest automotive standards such as the V-model and A-Spice Level 3 and carry out test and validation processes in-house.
Our customers have the option of taking over partial developments, e.g. the software or certain parts of it. All other project scopes are taken over by us in accordance with the contractual agreements.
We offer comprehensive manufacturing services for complex automotive products such as BMS and power electronics. We provide support with our expertise in technology, industrialization, logistics and production and guarantee high-quality production in large quantities.
For less complex products, we take over production according to customer specifications. The customer is responsible for development, while we carry out production according to the agreed specifications.
