Timing violation of 7025L20PFGI SRAM

Hi Jason,

Thank you for posting your question online.
Let me check on this with the Memories Support Team.

Best Regards,
OV_Renesas

Dear OV_Renesas,

Thanks for the update. I’ll await the details.

Best,
Jason Shih

Dear Jason,

Could you please share the speed grade and orderable part number for this request?

Best Regards,
OV_Renesas

Dear OV_Renesas,

I think the orderable part number is 7025L20PFGI, but I'm not sure what "speed grade" means. If it refers to access time, then I am hoping for 20 ns.

Additionally, the compressed Verilog model file I previously obtained from your team is named "idt7025U.verilog.1" (I used it directly without altering any timing settings). Should I provide you with the file again for confirmation of the settings within?

Best,
Jason Shih

Dear Jason,

Apologies for the delay.
The device you mentioned is a 20ns speed grade dualport, please see the datasheet Ordering information for naming convention with regarding to speed, etc.

The timing conflicts are related with using a 10ns clock on a 20ns device.
Each timing parameter listed in the datasheet should be checked individually for read and write against your inputs. One way to do this is to slow the clock and input stimulus until you get the circuit working then doublecheck the timing variables and then minimize delays.

The model has a very good readme file to explain model customization. The model default is a 15ns device and should be changed to 20ns. Please follow the guidelines as stated and this will help you satisfy the requirements for your design.

Best Regards,
OV_Renesas

Dear OV_Renesas,

I think "taa" means "Access Time from Address" (as shown in the right picture), so I need to change this value to 20 ns. Is that correct?

And if I want to change the device speed, I just need to adjust taa to 15/17/20/25/35/55.

Additionally, I want to confirm whether I can only use a 20 ns clock for a device with a 20 ns access time, or can't it be a higher/lower value?

Thank you very much for your response!

Best,
Jason Shih

Dear OV_Renesas,

I think "taa" means "Access Time from Address" (as shown in the right picture), so I need to change this value to 20 ns. Is that correct?

And if I want to change the device speed, I just need to adjust taa to 15/17/20/25/35/55.

Additionally, I want to confirm whether I can only use a 20 ns clock for a device with a 20 ns access time, or can't it be a higher/lower value?

Thank you very much for your response!

Best,
Jason Shih