K4N56163QF Datasheet, PDF (28/73 Pages) Samsung semiconductor – 256Mbit gDDR2 SDRAM

K4N56163QF-GC
256M gDDR2 SDRAM
Off-Chip Driver (OCD) Impedance Adjustment
gDDR2 SDRAM supports driver calibration feature and the flow chart below is an example of sequence. Every calibration
mode command should be followed by “OCD calibration mode exit” before any other command being issued. MRS should
be set before entering OCD impedance adjustment and ODT (On Die Termination) should be carefully controlled depend-
ing on system environment.
Start
MRS shoud be set before entering OCD impedance adjustment and ODT should
be carefully controlled depending on system environment
EMRS: OCD calibration mode exit
EMRS: Drive(1)
DQ & DQS High; DQS Low
EMRS: Drive(0)
DQ & DQS Low; DQS High
ALL OK
Test
Need Calibration
EMRS: OCD calibration mode exit
ALL OK
Test
Need Calibration
EMRS: OCD calibration mode exit
EMRS :
Enter Adjust Mode
EMRS :
Enter Adjust Mode
BL=4 code input to all DQs
Inc, Dec, or NOP
BL=4 code input to all DQs
Inc, Dec, or NOP
EMRS: OCD calibration mode exit
EMRS: OCD calibration mode exit
EMRS: OCD calibration mode exit
End
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Rev 1.6 (Apr. 2005)