design review especially inductor selection

JITHU T P

Part Number: LM5169

I would like to design a isolated supply of 3.3V from a 15V supply. I would like to use the vout2 for this purpose as isolated power. vout1 will be left unconnected to load.

1) is keeping the vout1 unconnected a issue? if so is there any other solution to get isolated supply

2) the inductor i have selected is SRF0703-150M Does this meet the purpose?

over 2 years ago

0 Richard Fu22 over 2 years ago

TI__Mastermind 30895 points

Hi,

1) You should be ok since Vout1 is loaded utilizing a feedback divider.

2) Usually you will want a coupled inductor. Please refer to 9.2.2.2 in the application datasheet for inductor selection.

Regards,

Richard

0 JITHU T P over 2 years ago in reply to Richard Fu22

Prodigy 140 points

I have referred section 9.2.2.2 and selected this value and inductor.

Is this enough?

0 JITHU T P over 2 years ago in reply to JITHU T P

Prodigy 140 points

could you give some suggestions?

0 Richard Fu22 over 2 years ago in reply to JITHU T P

TI__Mastermind 30895 points

Hi Jithu,

I would just make sure that the inductor has a 1:1 turns ratio. I was not able to see this spec on the datasheet, which is why I had my doubt. As long as you have a 1:1 ratio, and followed the guidelines in the application section, it should be ok.

Regards,

Richard

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design review especially inductor selection