HY5S5B2CLFP-6E Datasheet, PDF (34/54 Pages) Hynix Semiconductor – 256M (8Mx32bit) Mobile SDRAM

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256Mbit (8Mx32bit) Mobile SDR Memory
HY5S5B2CLF(P) Series
READ to WRITE
Data from READ burst must be completed or truncated before a subsequent WRITE command can be issued. If trun-
cation is necessary, the BURST TERMINATE command must be used, as shown in next fig.
CLK
Command
READ
BURST
W RITE
Address
BA, Col
n
BA, Col
b
CL =2
DQ
Don Don'
DIb0 DIb1 DIb2 DIb3
CL =3
Don Don'
DIb0 DIb1 DIb2 DIb3
DQ
1) DO n = Data Out from column n; DI b = Data In to column b
Don't Care
Read to Write
Note:
1. Same bank, same ROW address: When the write command is executed at the same ROW address of the same bank as the preced-
ing read command, the write command can be performed after an interval of no less than 1 clock. However, DQM must be set High
so that the output buffer becomes High-Z before data input.
2. Same bank, different ROW address: When the ROW address changes, consecutive write commands cannot be executed; it is nec-
essary to separate the two commands with a precharge command and a bank active command.
3. Different bank: When the bank changes, the write command can be performed after an interval of no less than 1 cycle, provided
that the other bank is in the bank active state. However, DQM must be set High so that the output buffer becomes High-Z before data
input.
Rev 1.5 / Aug. 2008
34