K4N56163QF Datasheet, PDF (42/73 Pages) Samsung semiconductor – 256Mbit gDDR2 SDRAM

K4N56163QF-GC
256M gDDR2 SDRAM
Reads Intrrupted by a Read
Burst read can only be interrupted by another read with 4 bit burst boundary. Any other case of read interrupt is not
allowed.
Read Burst Interrupt Timing Example: (CL=3, AL=0, RL=3, BL=8)
CK/CK
CMD ^{Read A}
NOP
Read B
NOP
NOP
NOP
NOP
NOP
NOP
NOP
DQS/DQS
DQs
A0 A1 A2 A3 B0 B1 B2 B3 B4 B5 B6 B7
Notes:
1. Read burst interrupt function is only allowed on burst of 8. Burst interrupt of 4 is prohibited.
2. Read burst of 8 can only be interrupted by another Read command. Read burst interruption by Write command or
Precharge command is prohibited.
3. Read burst interrupt must occur exactly two clocks after previous Read command. Any other Read burst interrupt
timings are prohibited.
4. Read burst interruption is allowed to any bank inside DRAM.
5. Read burst with Auto Precharge enabled is not allowed to interrupt.
6. Read burst interruption is allowed by another Read with Auto Precharge command.
7. All command timings are referenced to burst length set in the mode register. They are not referenced to actual burst.
For example, Minimum Read to Precharge timing is AL + BL/2 where BL is the burst length set in the mode register
and not the actual burst (which is shorter because of interrupt).
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Rev 1.6 (Apr. 2005)