AM2434: LPDDR FSP1/2 Clock Settings

Hello,

FSP1, FSP2 can be lower than 533MHz per the JEDEC LPDDR4 specification.

We do not support the lower rates in the tools and configurations from TI. Also, FSP1 is not supported and only FSP2 is used.

Regards,

Anita

Hi Anita,

Thanks for the support. I received a follow-up question from y customer.

Could you please tell me the specific way to specify this?
Will it work if I simply change the values of FSP1 and FSP2 definitions in the generated header file to 1/2 of 150 MHz? (When this setting is changed on the tool, some parameters in the header file are changed as shown in the figure below)

Best regards,

Mari

Hi Mari,

I cannot see the image shown. Can you please share a clear image? 

Thanks,

Anita

Hi Anita,

I sent you the .syscfg file via email a week ago. Do you have any updates for me?

Best regards,

Mari Tsunoda

Mari, attached is a config for 200MHz operation which works on my EVM.  I could not get 150MHz to work yet, but not sure why, may have something to do with the IO settings.  Have you simulated with 150MHz?  I think the drive strength and terminations settings may need to be different than the default that is in the Register Configuration Tool

Regards,

James

/cfs-file/__key/communityserver-discussions-components-files/908/AM64x_2D00_LP4_5F00_50_5F00_200.h

Hi James,

Unfortunately, they have not simulated with 150MHz. Do you know what driver strength it needs to be configured to for the 150MHz to work?

This thread is also regarding the same customer. https://e2e.ti.com/support/microcontrollers/arm-based-microcontrollers-group/arm-based-microcontrollers---internal/f/arm-based-microcontrollers---internal-forum/1181602/am2434-drv_str-bits-in-padconfig-registers?tisearch=e2e-sitesearch&keymatch=%25252520user%2525253A499871#

They are also having issues with driver strength. Not sure how this might be related, but just some additional info.

Best regards,

Mari Tsunoda

Mari, only simulations would be able to give us the optimal IO settings.  Were they able to get the 200MHz configuration to work?  Why do the specifically need to run the DDR interface at 150MHz?  Is there a technical reason?  Most customers would want the interface the run as fast a possible, to increase idle time when not being used.

Regards,

James