LM74900-Q1: Query on scheme selection of Power Mux with Priority

Yuanchen Zhu

Part Number: LM74900-Q1
Other Parts Discussed in Thread: LM74900

Tool/software:

Dear TI Experts,

We plan to design a power mux with priority for multiple 24V power rails. Since we need to monitor the status of each power rail, it seem to us that we have to choose to use #FLT pin in LM74900 instead of LM74800. However, we actually do not really need over current detection, and plus we have quite limited PCB area in our design. Is there any way that we can simplify the design as we do not need this Over Current function? Or is there any way that we can still get the status of power rails in the case of using LM74800?

Hope you kindly give some suggestion. Would appreciate your help.

Thanks,

Yuanchen

11 months ago

0 Shiven Dhir 11 months ago

TI__Guru 51815 points

Hi Yuanchen,

Customer can disable the overcurrent protection features by shorting the sense resistors. With this, they can also eliminate the use of components on TMR,ILIM,IMON.

Regards,

Shiven Dhir

0 Yuanchen Zhu 11 months ago in reply to Shiven Dhir

Intellectual 425 points

Hello, Shiven. Thanks for your quick reply. Just double check my understanding, in that case so you mean we can leave pin TMR,ILIM,IMON floating, and just short Rsense and Rset for CS+ and CS- pin. Is that right? Please correct me if I am wrong.

Yuanchen

+1 Shiven Dhir 11 months ago in reply to Yuanchen Zhu

TI__Guru 51815 points

Hi Yuanchen,

You can ground ILIM, TMR, Open IMON, short CS+ to CS-

Regards,

Shiven Dhir

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LM74900-Q1: Query on scheme selection of Power Mux with Priority