How to select the decoupling capacitor of DA14681 external flash?

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song
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How to select the decoupling capacitor of DA14681 external flash?

In the reference design of Dialog, the decoupling capacitor specification of the external flash chip is 0.1uf 16V 10% X7R 0402, can it be changed to 0.1uf 10V 10% X7R 0201 or 0.1uf 16V 10% X5R 0201?

The specification we use now is 0.1uf 6.3V 10% X5R 0201, and then the capacitor is damaged. What's the reason?

Thanks.

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PM_Dialog
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Hi song,

Hi song,

我将检查它内部和团队在一起,我很快就会回来的l let you know shortly which is the recommend decoupling capacitor for the external flash.

Thanks, PM_Dialog

PM_Dialog
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Hi song,

Hi song,

I would recommend you to use 1uF decoupling capacitor instead of 100nF. You could use either 0.1uf 10V 10% X7R 0201 or 0.1uf 16V 10% X5R 0201 but I would suggest you increase the capacity to 1uF. The capacity of the decoupling capacitor is changed to 1uF in our designs. Not sure why 0.1uf 6.3V 10% X5R 0201 was damaged.

Thanks, PM_Dialog

song
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I have found that only the

I have found that only the decoupling capacitor of VDDIO is retained in your wearable design example. In my design, a 0.1uf capacitor is added to the VCC pin of external flash.The decoupling capacitors of V18 and V18P in your design are both 16V, while my design USES 10V. Today I found that the capacitor of V18 in my equipment is damaged. Why is it 16V?Is the damage to the V18 decoupling capacitor related to the external flash decoupling capacitor?

PM_Dialog
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Hi song,

Hi song,

Which capacitor is used in the V18? Probably you should refer to the capacitor’s specification, so not sure why is happened.

Thanks, PM_Dialog

song
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C4 in the attachment.

C4 in the attachment.

Attachment:
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Hi song,

Hi song,

It’s correct - Decoupling ceramic capacitors (C4 & C5) of 10μF (0603 package, 16V) must be placed as close as possible to the V18 and V18P pins. The suggested decoupling capacitor for C4 & C5 is: CAP CER 16V 20% X5R - 10 μF - 0603

Thanks, PM_Dialog