am5726: Abnormal DDR3 DQS waveform

Allen35065

Part Number: AM5726
Other Parts Discussed in Thread: AM5726

Hi expert,

Ctm found on AM5726 DDR3L DQS waveform is abnormal as below. Blue is CE and Yellow is DQS. When DQS signal is over, it take much time to return.

Ctm also have product on DRA62x using same DDR3 chip and did not see this trailing.

Could you please suggest what is the reason for the long trailing? Thank you.

Regards,

Allen

over 8 years ago

0 Biser Gatchev-XID over 8 years ago

TI__Guru**** 393215 points

The factory team have been notified. They will respond here.

0 sivak over 8 years ago in reply to Biser Gatchev-XID

TI__Genius 9655 points

Allen

Can you share your DDR configuration? How is this different from the DRA62x?

Do you know when the DQS is captured? Is it between READ's or WRITE's?

Regards, Siva

0 Allen35065 over 8 years ago in reply to sivak

TI__Expert 4645 points

Hi Siva,

I will check with ctm. Do you mean DDR3 controller in AM572x is same as DRA62x?

Regards,

Allen

0 sivak over 8 years ago in reply to Allen35065

TI__Genius 9655 points

Allen

Since you mentioned the customer does not see the same behavior with DRA62x, I was curious to know what the differences are between the DRA62x system and the AM572x in terms of the DDR controller settings, DDR3 memory and DRAM settings being used.

If you have those details, can you help share them to debug this issue?

Regards, Siva

0 Allen35065 over 8 years ago in reply to sivak

TI__Expert 4645 points

Hi Siva,

I used AM57x EMIF tools to calculate the DDR controller setting parameter and found there was some difference in ctm's settings. I asked customer to compare the parameters and do some tests. Currently they did not give feedback. So this issue is pending by customer and I will let you know when they have results.

Thank you.

Allen

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am5726: Abnormal DDR3 DQS waveform