M2S56D20TP Datasheet, PDF (28/36 Pages) Mitsubishi Electric Semiconductor – 256M Double Data Rate Synchronous DRAM

DDR SDRAM (Rev.0.0)
Sep.'99 Preliminary
MITSUBISHI LSIs
M2S56D20/ 30 TP
256M Double Data Rate Synchronous DRAM
[Read Interrupted by Burst Stop]
Burst read operation can be interrupted by a burst stop command(TERM). READ to TERM interval
is minimum 1 CLK. A TERM command to output disable latency is equivalent to the /CAS Latency.
As a result, READ to TERM interval determines valid data length to be output. The figure below
shows examples of BL=8.
Read Interrupted by TERM (BL=8)
/CLK
CLK
Command
READ
TERM
DQS
CL=2.5
DQ
Command
DQS
READ
Q0 Q1 Q2 Q3 Q4 Q5
TERM
DQ
Q0 Q1 Q2 Q3
Command
READ TERM
DQS
DQ
Q0 Q1
CL=2.0
Command
DQS
DQ
Command
DQS
DQ
Command
DQS
DQ
READ
TERM
READ
Q0 Q1 Q2 Q3 Q4 Q5
TERM
READ TERM
Q0 Q1 Q2 Q3
Q0 Q1
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ELECTRIC
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