Other NXP ProductsのトピックLS1046A PDN design

LS1046A PDN design

Nareshvarikuntla — Mon, 21 Jun 2021 10:57:54 GMT

Dear NXP,

I would like to optimize decoupling capacitor around LS1046A. Please let me know the instantaneous current profile drawn by LS1046A.

Also it would be nice if you can share documents related LS1046A PDN design.

Regards,

Naresh V.

Re: LS1046A PDN design

Bulat — Mon, 21 Jun 2021 13:02:55 GMT

We do not have such a "current profile".

Please take a look at AN5252 application note ("Design checklist", can be found on our web site), its section 4 provides power design recommendations.

Regards,

Bulat

Re: LS1046A PDN design

Nareshvarikuntla — Mon, 21 Jun 2021 13:17:16 GMT

Dear NXP,

I have already gone through AN5252. It doesn't have information on current profile and that is why I raised query in this forum.

NXP reference board has 8 layer. But I will be using board with more than 10 layers. In that I will allocate pair of layers for embedded capacitance so that I can reduce the decoupling capacitors and improve the component density.

So for this , I need the instantaneous current drawn by each power supply and their current profile. This information is missing in that datasheet or any other application notes. Kindly share this information.

Also please do let me know how NXP decided on on number of decoupling capacitors and placement of capacitors for reference board. Kindly share relevant information.

Re: LS1046A PDN design

Bulat — Wed, 23 Jun 2021 10:35:00 GMT

As I already wrote, we do not have documents with 'current profile'.

To estimate current consuming by the cores and I/O interfaces, you can refer to data sheet. Tables 7 and 10 provides power numbers.

If you take a look at the AN5252, you could find our recommendations about number of decouplng capacitors and their placement. Search for 'General Power supply decoupling' section.

Regards,

Bulat

Re: LS1046A PDN design

Nareshvarikuntla — Wed, 23 Jun 2021 10:43:11 GMT

Dear NXP,

Please do let me know how decoupling capacitors for LS1046RDB decided. Please share the simulations and Notes.

I believe this information will be available at least with the LS1046RDB board designer. Please share the information.