66AK2H12 DDR3A drive strength

RY9983

Hello,

I encountered K2H DDR3A read error in our custom target board.
I have a question.

Question)
- Do DDR3A address pins have a sufficient drive strength to drive 8 or 16 DDR3 SDRAM?
(Especially, we are interested in the drive performance when multi address lines are changed simultaneously.)

- Can I change the drive strength of DDR3A Address/Data line?

Our trouble)
We are using following DDR3 memory under DDR3A:
DDR3 memory : 4Gb (x8b width) x8 devices = 4GByte

1600 data rate .. the issue happens
800 data rate .. the issue does not happen

We have monitored DDR3A_CK+/- and DDR3A_Ax.
Actually, we can observed blunt wave signal in DDR3A_Ax.

Best regards, RY

over 10 years ago

0 Senthilkumar Srinivasan over 10 years ago

TI__Mastermind 43660 points

Hello RY,

The issue might be due to signal integrity. Have you followed all the guidelines provided in DDR3 design requirements document SPRABI1B ?

- Do DDR3A address pins have a sufficient drive strength to drive 8 or 16 DDR3 SDRAM?
(Especially, we are interested in the drive performance when multi address lines are changed simultaneously.)

Yes, as specified in the data manual section 10.9, the DDR3 pins have sufficient drive strength to drive up to 8 SDRAMs.

- Can I change the drive strength of DDR3A Address/Data line?

I think you cannot change the DDR3 drive strength. It is recommended to use 240 ohm resistor on ZQ pins for drive strength calibration.

By seeing your issues, i suspect you are having signal integrity issues. I would suggest you to do simulation on DDR lines and try to find the cause for this issue.

You may also find the below link useful.

http://e2e.ti.com/support/dsp/c6000_multi-core_dsps/f/639/p/347938/1222568.aspx#1222568

Regards,

Senthil

0 RY9983 over 10 years ago in reply to Senthilkumar Srinivasan

Guru 10570 points

Senthil-san,
Thanks for your helping!

I have a plan to change design to increase SDRAM size.
I am referring Table1 in sprabi1b(P10).
It seems that K2H supports 16 SDRAMs.

What do you think about it?

Best regards, RY

0 Senthilkumar Srinivasan over 10 years ago in reply to RY9983

TI__Mastermind 43660 points

Hello RY,

Yes, you can use 16 SDRAMs in x8, 2 ranks configuration. Hope you are not considering ECC support for your application. If you need ECC support please refer Table 4 in SPRABI1B.

Regards,

Senthil

0 RY9983 over 10 years ago in reply to Senthilkumar Srinivasan

Guru 10570 points

Senthil-san, thanks!!

May I ask once more?
I would like to consult to 3rd Party about high speed DDR3 design (DDR3-1600M datarate).

Can you tell me the 3rd party like this?
They have already succeeded to make own target board using K2H/K2E with DDR3-1600.

Best regards, RY

0 Senthilkumar Srinivasan over 10 years ago in reply to RY9983

TI__Mastermind 43660 points

Hello RY,

I would suggest you to contact your local FAE to get the 3rd party details for the high speed DDR3 design.

Regards,

Senthil

0 Senthilkumar Srinivasan over 10 years ago in reply to Senthilkumar Srinivasan

TI__Mastermind 43660 points

Hello RY,

I also forwarded your request to the concern team. They might get back with some suggestions.

Regards,

Senthil

0 Tom Johnson 16214 over 10 years ago in reply to Senthilkumar Srinivasan

TI__Mastermind 46460 points

Our EVM providers are able to provide this service. The K2E EVM is produced by eInfochips. The link is: https://www.einfochips.com/index.php/partnerships/texas-instruments/k2e-evm.html. The K2H EVM is produced by Advantech. The link is: http://www.advantech.com/Support/TI-Evm/EVMK2HX.aspx.

Tom

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66AK2H12 DDR3A drive strength