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JeremyH
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Using a 0402 inductor

Hello,

I would like to use in my design the smallest inductor possible, but I can't find requirements besides the typical inductance.
What are the other requirements (rated current, Q / DC resistance, resonant frequency...)?
Would a 0402 model like this one work: TDK MLF1005L2R2K - http://product.tdk.com/en/catalog/datasheets/inductor_commercial_standar... ?
If yes, would using it have a significant impact on the DCDC's efficiency / global power usage?

Regards,
Jeremy

Device: 
MT_dialog
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Hi JeremyH

Hi JeremyH

As with most small sized inductors, this '0402' (1005M) has a too low saturation current: it is stated to be 30 mA max.
For buck-mode applications we need 100mA minimum.
Besides this, also the ESR is high, 1.3 Ohm max. Our requirement for the DA14580 is 1 Ohm max, preferably lower.

Even the larger sizes (1608M and 2012M) are not good enough.
So, in my opinion this is not a good inductor type for our purpose.

Alternatives:
Tayo Yuden: 0603 size: BRL1608T2R2M; BRC1608T2R2M; CBMF1608T2R2M.

Sunlord: 0603 size: MPH160809S2R2.

Coilcraft: 0603 size: PFL1609-222MEU.

TDK: 0805 size: TDK MLZ2012A.
TDK: 0603 size: TDK MLZ1608A.

Some informations can be found in doc AN-B-018 checklist for schematic and pcb layout.

Thanks MT_dialog

JeremyH
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Last seen: 4 years 9 months ago
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Hi MT_dialog,

Hi MT_dialog,

Thank you for your answer.
I forgot to mention I'm working in boost mode.
Does it change anything?

Best,
Jeremy

MT_dialog
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Hi JeremyH 

Hi JeremyH 

If you are working in boost mode the requirements are doubled against you, so yes it does. For example if for buck mode applications the saturation current need was 100mA in boost mode would be 200mA.

Thanks MT_dialog 

JeremyH
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Last seen: 4 years 9 months ago
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Ok thanks

Ok thanks

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