• State Resolved
  • Replies 4 replies
  • Subscribers 98 subscribers
  • Views 150 views
  • Users 0 members are here
Support feedback
Options
Options
Related

TDA4VH-Q1: DDR Timing Parameters Adaption

Kevin Peng
Expert 4368 points

Part Number: TDA4VH-Q1
Other Parts Discussed in Thread: TDA4VH

Hi TI Experts,

 

Customer has SOP TDA4VH with Micron: MT53E1G32D2FW for some time with no problems. Due to some reasons, they have to change it to Rayson: RS1G32LO4D2BDS (Micron Wafers). We have told customer they will require spend time & efforts to test & adapt the new DDR by themselves making a number of new boards with pressure test, and customer will do that.

 

In the meanwhile, before customer starts the adaption works, they have summarized an Excel sheet screenshot below with detailed comparison between Micron & Rayson by extracting the key specs from the datasheet. Customer has done most of the analyzing works, and they found the most challenge & difference between these two DDR come from the timing parameters below, especially tPW_RESET & tFAW. The following timing values are the one customer used with Micron with no problems, and based on the difference in Rayson described below, we may need modify some of the values correspondingly, could you help comment on below two points please?

  • Do you see any obvious effects/challenge for these timing parameter difference?
  • Any suggested new timing values input especially for tPW_RESET & tFAW? (customer will make the board to pressure test)

 

I have also shared the datasheet to you privately through email, please have a look.

Thanks,

Kevin

  • 0
    TI__Mastermind 41540 points

    Hi Kevin,

    Acknowledging the E2E ticket - will review tomorrow.

    Thanks,
    Kevin

  • +1 in reply to Kevin S
    TI__Mastermind 41540 points

    Hi Kevin,

    Kevin Peng said:
    I have also shared the datasheet to you privately through email, please have a look.

    As a note, I didn't see any timing information in the Rayson datasheet.

    Kevin Peng said:
    • Do you see any obvious effects/challenge for these timing parameter difference?
    • Any suggested new timing values input especially for tPW_RESET & tFAW? (customer will make the board to pressure test)

    Is the question whether the customer can use 1 single set of values for both memories? More specifically, are you asking if the customer can use the Micron values with the Rayson memory?

    Some comments:

    • tFAW: tFAW can sometimes be speed grade dependent. Memories supporting the fastest data rate (4266 MT/S) typically support 30 ns. I see that Rayson has two variants of RS1G32LO4D2BDS (see image below). Which version is the customer using, and which datasheet is the customer reviewing? If the customer is planning to use the faster speed grade, the I would suggest they double check this value with Rayson. If 40 ns is required, then they should use a value of 40 ns.
    • tPW_RESET: This is defining the time RESETn should be held low when power is stable. It is similar to tINIT1 with the distinction that RESET was applied with no power interruption. Is it correct that Rayson's memory requires longer tPW_RESET compared to tINIT1?
    • tREFI: Customer already appears to be using a faster refresh value - no concerns here to maintain this same value.
    • tXSR: Similar to tPW_RESET, the number reported for Rayson maybe needs clarification. However, the customer is already using a value that satisfies both memories so I do not have any concerns. As a side note, this parameter shouldn't matter if the customer is not putting the memory into a self-refresh state.

  • 0 in reply to Kevin S
    TI__Expert 4368 points

    Hi Kevin S,

    Thanks for the feedback!

    Customer is using the Rayson variant with 4266Mbps. I have shared your comments to customer & Rayson, Rayson has mode the modifications below:

    • tXSR     = MAX ( tRFCab + 7.5ns , 2nCK ) 
    • tFAW     = 30ns
    • tPW_RESET    = 100ns 
    • tREFI   = 3.906us

    Now it looks much better compared with Micron customer used previously, I will get back if there are any more support need, thanks a lot!

    Thanks,

    Kevin

  • 0 in reply to Kevin Peng
    TI__Mastermind 41540 points

    Thanks for confirming Kevin. We will close this ticket. If further help is needed, feel free to reply back or open a new ticket and reference this ticket.

    Thanks,
    Kevin