How to properly perfrom DDR3 calibration for DDR running below 300MHz (at 278MHz)

[vasylzakharko]

Hi,

We use custom IMX6SL board with DDR3-1600 memory.

I have got question how to properly perfrom DDR3 calibration running at 278MHz? So far I see that DDR Stress tester tool uses calibration frequencies ranges of 300-528MHz.

Also we use custom PLL2 clock frequency of 480MHz (configured in SPL)

Thank you!

[nxf63675]

Hi @vasylzakharko,

The JEDEC spec imposes the lower limit of operation of 300MHz for DDR3; it's a limitation of the on-chip DLL of the memory device, so that's why the tool does not support lower frequencies.

Regards,

Israel.