| 摘要 |
The termination resistor of an electronic apparatus is connected in series with a thermistor PTC switch thermally coupled to the resistor. Excessive power dissipation in the resistor causes the PTC switch to trip, and the increased total resistance limits power dissipation in the resistor to safe levels. The PTC switch and the resistor may be merely in close physical proximity to one another to achieve the thermal coupling. Alternatively, the two may be fabricated as a unit assembly whose form factor is that of, or is similar to that of, the resistor that would otherwise be used by itself.
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