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JEDEC STANDARD

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JESD79E<br />

Page 37<br />

CK<br />

CK<br />

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11<br />

COMMAND<br />

ADDRESS<br />

WRITE<br />

Bank,<br />

Col b<br />

NOP NOP NOP READ NOP<br />

tWTR<br />

Bank<br />

Col n<br />

DQS<br />

tDQSS(max)<br />

CL = 2.5<br />

DQ<br />

DI<br />

b<br />

DM<br />

Don’t Care<br />

DI b = Data In for column b<br />

Three subsequent elements of Data In are applied in the programmed order following DI b<br />

A non-interrupted burst of 4 is shown<br />

tWTR is referenced from the first positive CK edge after the last Data In pair<br />

tWTR = 2tCK for optional CL = 1.5 (otherwise tWTR = 1tCK)<br />

A10 is LOW with the WRITE command (AUTO PRECHARGE is disabled)<br />

The READ and WRITE commands are to the same device but not necessarily to the same<br />

bank<br />

Example is for a x4 or x8 device where only one Data Mask and one Data Strobe are used.<br />

For a X16, UDM and LDM would be required, as well as UDQS and LDQS.<br />

Figure 25<br />

WRITE TO READ - Max tDQSS, NON -INTERRUPTING

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