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新组件的方法解决低电压电路保护的挑战
保护电路是一个吃力不讨好的设计注意事项:这是一个类似保险的成本是不被赏识的时候一切都好;当问题发生时,它将提供对预期的充分保护甚至难以预料的事件。设计者需要提供与应用程序要求相匹配的电路保护,以对抗任何内部和外部事件,这可能会对系统可靠性产生负面影响,甚至可能导致彻底失败。根据应用程序和系统拓扑,保护可能需要在一个或多个点或包括单个组件,在内部阶段之间的互连,并在系统外部信号和电源接口。
有许多长期的,久经考验的,习惯的方式来实施保护,也有新的,创新的方法和组件专为一些特定的,越来越普遍的保护情况。工程师面临的第一个挑战是了解他们需要保护什么。其中关注的是:
过压(稳态和暂态)
过流,要么只是超过一个适度的保护带阈值或作为一个完整的短路(再次,稳态和瞬态)
高热(通常是过热,但冷也可考虑)
反向电池连接(最常与汽车相关)
电磁干扰引起的瞬变
Some of these protecTIon concerns are due to an internal failure such as when a power device fails and develops a short circuit; others are due to external events such as accidental shorTIng of the output of a power supply to ground or a terminal of a component to the power rail; while others are the result of large-scale external issue such as lightning hitTIng the device directly or nearby. Further, some faults, such as shorTIng a power-supply‘s output, may be steady state, while some are transient events, such as those induced by EMI/RFI (although the failure they induce may be long lasting, of course).