DRA821U: 16 Bit DRAM possible

Rene Straub

Part Number: DRA821U
Other Parts Discussed in Thread: DRA821

Tool/software:

Hello TI,

we understand the DRA821 is intended to use 32 bit DRAM.Is it possible to use 16 data bits only. The user manual mentions two independent 16 bit channels.

Our application doesn't not the performance improvement of 32 bits and could benefit from a simpler/smaller layout.

However the DDR controller section datasheet does not describe a 16 bit mode. I can also image that there will be issues with the ECC system.

Just curious if you know about tests or even customers using a 16 vit DRAM interface.

Best regards

-Rene

26 days ago

0 Kevin S 23 days ago

TI__Mastermind 38510 points

Hi,

I apologize for the delay.

You should be able to configure the DDR controller / PHY for 16-bit (single channel) LPDDR4 memory. You would need to tie-off the unused DQS signals.

I think it is rare for a TDA4x or DRA8x customer to use 16-bit LPDDR4. The TDA4x and DRA8x boards all have 32-bit memories populated on them, but it is possible to configure the controller / PHY in a 16-bit mode even with 32-bit memories attached.

Regards,
Kevin

0 Kevin S 23 days ago in reply to Kevin S

TI__Mastermind 38510 points

Below is the link to the latest DDR register configuration tool which can be used to generate register settings for 16-bit DQ width / single rank.

https://dev.ti.com/sysconfig/?product=TDA4x_DRA8x_AM67x-AM69x_DDR_Config&device=J7200_DRA821_SR1.0_alpha

+1 Rene Straub 23 days ago in reply to Kevin S

Prodigy 120 points

Thanks Kevin for the information and the tool link.
We'll have to decide whether we go with the proven 32 bits or if we try out 16 bit with a minimal risk of problems.

-Rene

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DRA821U: 16 Bit DRAM possible