| 摘要 |
The present invention relates to an electric protective circuit comprising an electric fuse, including a solder (3), and an electric resistance loop (10) connected in series with the fuse (1), the fuse and loop being mounted on a substrate (11). The solder (3) will melt at elevated temperatures caused by heating of the substrate (11), and is surrounded by a material (8) which protects the solder (3) against the oxidizing effect of the surrounding air, and is applied in a region (9) surrounding the solder (3) and delimited by barrier walls (7), therewith enabling the solder (3) to contract onto the connecting terminals (4a, 4b) when it melts, therewith breaking the current path. The material (8) is temperature-stable in a solid state at normal fuse operating temperatures. The resistance loop (10) includes current-conducting paths (12) mutually connected with bridging elements (13), whose electrical resistance is much lower than the electrical resistance of the current-conducting paths (12), and trimming elements (14) for adjusting the resistance of the loop.
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