LM5050-1: What is the function of "D3" in Figure 31 of data sheet

Fraser Lawson1

Part Number: LM5050-1

Hello.

I wish to use the LM5050-1 in a Reverse Polarity Protection application. Figure 31 shows a diode D3 between IC ground and circuit ground.

It is not present in most of the other Figures in the data sheet.

My question is - Is D3 required for reverse polarity protection applications?

If yes, then can you explain why?

Thanks

over 5 years ago

0 Karikalan Selvaraj over 5 years ago

TI__Genius 16305 points

Hello Fraser,

Diode D3 is required mainly for reverse polarity protection.

It block reverse polarity from damaging the IC when a reverse input is applied, as the reverse input can conduct very high current through its ESD diode from GND to IN pin or VS pin.

D3 blocks this reverse current into the IC and prevents damage to the IC.

Regards,

Kari.

0 Fraser Lawson1 over 5 years ago in reply to Karikalan Selvaraj

Prodigy 240 points

Thank you for your prompt reply. This was not clear in the data sheet, so thank you for confirming this fact.

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LM5050-1: What is the function of "D3" in Figure 31 of data sheet