What is the effect of connecting a pullup to pin A3 (DNU) on S26KS_S HyperFlash?

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GrCa_1363456
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Can a pullup be connected to pin A3 on S26KS512S… to allow backwards compatibility with a similar memory?

Section 15 of the S26KS512S HyperFlash datasheet notes, “Changed 24-Ball FBGA package pin A3 to DNU”, under “Description of Change” for Rev I and refers to an ECN 5844610.

Is ECN 5844610 available for review?

I would appreciate recommendations on which pins should have resistors in line that could be left unpopulated when the pin is DNU or RFU.

I would also appreciate recommendations on which pins should have resistors to power or ground that could be left unpopulated when not used or populated when needed to allow alternative memories and future proof the design?

Greg

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Apurva_S
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100 likes received 500 replies posted 250 solutions authored

Hi Greg,

Please find the layout guide for HyperFlash memory on this link - https://www.cypress.com/documentation/application-notes/an211622-hyperflash-and-hyperram-layout-guid...

It has the description for DNU pin. Let me know if this answers your question.

Regards.

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Apurva_S
Moderator
Moderator
Moderator
100 likes received 500 replies posted 250 solutions authored

Hi Greg,

Please find the layout guide for HyperFlash memory on this link - https://www.cypress.com/documentation/application-notes/an211622-hyperflash-and-hyperram-layout-guid...

It has the description for DNU pin. Let me know if this answers your question.

Regards.

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