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jfolsom
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DA14580 Vdcdc Filtering

In AN-B-018 section 3.4, you suggest using a 4-10mm meandering trace between the Vdcdc/Vdcdc_RF decoupling caps. Can I instead create this inductance with a ferrite bead or chip inductor? About how much inductance are you targeting?

Thanks!

BB_Dialog
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Joined: 2013-12-05 14:44
Hi jfolsom,

Hi jfolsom,

of course, that's possible, but more expensive.
Not much inductance is needed, it's just for filtering the HF noise and HF ripple, the inductance forms a low-pass filter together with the 1µF at Vdcdc_RF.
The distance between the Vdcdc and the Vdcdc_RF pins already forces you to have a few mm track length. It's relatively easy to add a few mm in order to obtain several nH inductance.
5nH inductance or a little more is enough.

Best regards, BB_Dialog

jfolsom
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Thank you!

Thank you!