A reverse polarity protection controller when paired with an external N-channel MOSFET provides a low loss protection against input supply reversal. Reverse polarity protection controller does not provide reverse current blocking and is suitable for applications which need protection against input polarity reversal only.

An ideal diode controller when paired with an external N-channel MOSFET provides a low loss protection against both input supply reversal as well as reverse current flowing from output loads back to the input. Ideal diode controller is suitable for applications which need both input reverse polarity protection as well as reverse current blocking.

Figure 5-1 provides an overview of typical application use cases of reverse polarity protection controller and ideal diode controller. Typically for applications where output loads are DC/DC converters, voltage regulator followed by MCU/processors (Logic paths), input reverse polarity protection and reverse current blocking feature is required. For reverse polarity protection solution of the logic path ideal diode controller such as LM74700-Q1 is a suitable device.

For the input reverse polarity protection of loads which can potentially deliver energy back to the input supply such as Body Control Module (BCM) load driving paths, input reverse polarity protection is required but reverse current blocking is not a must have feature. For reverse polarity protection of similar applications , a reverse polarity protection controller such as LM74500-Q1 is a suitable device.