About DDR3L FOUR_ACT Window for four activates (tFAW)

[kojimiura]

I created DDR3L parameters (1200MT/S operation) using QCVS tool.
DDR3L uses MT41K512M16VRP-107IT (1866MT/S compatible).
From the DDR3L datasheet (tFAW) is
1866MT/S (device): 35ns
1333MT/S (operating frequency): 45ns
is.
The value of FOUR_ACT is not the operating frequency
35ns/1.67n = 21
Setting.
Is there not a problem?

[LFGP]

Regarding your very last question, my observation is that it could be 5.

on the other hand, I don't see any problem with the value for tFAW, but you need to run the respective test in QVCS tool and check the eye result.

[kojimiura]

Thank you.

[LFGP]

I need more context about what MPU your are using.

Please share some screenshots about QCVS tool process you are following and the datasheet you mentioned.

[kojimiura]

QCVS tool setting screen (CPU is T1024)
I have attached a screenshot of the DDR3L datasheet (1866 tFAW and 1333 tFAW).

[kojimiura]

I have one more question.
CKE_PLS(tCKE) is 5 in QCVS tool.
Looking at the attached data sheet, 4CK*1.666ns
Since it meets the 5.625ns standard,
The setting value of CKE_PLS is
Isn't 4 the correct answer?