电子熔丝TPS259271的限流值理解

TI的专家:

你好,我在用到电子熔丝TPS259271,有如下疑问:

一:手册中提到的限流值IOL,这个值是指平均值或者说有效值吗? 我设置限流时值应该怎么依据,依据我实际负载电流的有效值?

 (因为我测试发现我设置的限流值为IOL=1A(RLIM=10K)时,电流在750mA~1250mA波动,波形为接近正弦,频率100KHz。)

二:芯片集成了一个fast-trip comparator,当瞬态电流超过1.6*IOL时,芯片能实现快速关断MOS管?

三:综上来说,是不是可以这样理解,芯片具备瞬态的过流保护功能(由fast-trip comparator实现),而对发生的超过限流值IOL的过流现象的响应,只有很低的响应速度(由于比较电路有限的带宽限制导致)。

以下摘自手册:

During a transient short circuit event, the current through the device increases very rapidly. The current-limit
amplifier cannot respond very quickly to this event due to its limited bandwidth. Therefore, the TPS25927x
incorporates a fast-trip comparator, which shuts down the pass device very quickly when IOUT > IFASTRIP, and
terminates the rapid short-circuit peak current. The trip threshold is set to 60% higher than the programmed overload
current limit (IFASTRIP = 1.6 × IOL).

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