w9425g6jb Winbond Electronics Corp America, w9425g6jb Datasheet - Page 10

• Manufacturer Part Number: w9425g6jb
• Manufacturer: Winbond Electronics Corp America

7.2
7.2.1
7.2.2
7.2.3
7.2.4
7.2.5
7.2.6
7.2.7
( RAS = "L", CAS = "H", WE = "H", BA0, BA1 = Bank, A0 to A12 = Row Address)
The Bank Activate command activates the bank designated by the BA (Bank address) signal. Row
addresses are latched on A0 to A12 when this command is issued and the cell data is read out of
the sense amplifiers. The maximum time that each bank can be held in the active state is specified
as t
( RAS = "L", CAS = "H", WE = "L", BA0, BA1 = Bank, A10 = "L", A0 to A9, A11, A12 = Don’t
Care)
The Bank Precharge command percharges the bank designated by BA. The precharged bank is
switched from the active state to the idle state.
( RAS = "L", CAS = "H", WE = "L", BA0, BA1 = Don’t Care, A10 = "H", A0 to A9, A11, A12 =
Don’t Care)
The Precharge All command precharges all banks simultaneously. Then all banks are switched to
the idle state.
( RAS = "H", CAS = "L", WE = "L", BA0, BA1 = Bank, A10 = "L", A0 to A8 = Column Address)
The write command performs a Write operation to the bank designated by BA. The write data are
latched at both edges of DQS. The length of the write data (Burst Length) and column access
sequence (Addressing Mode) must be in the Mode Register at power-up prior to the Write
operation.
( RAS = "H", CAS = "L", WE = "L", BA0, BA1 = Bank, A10 = "H", A0 to A8 = Column Address)
The Write with Auto-precharge command performs the Precharge operation automatically after the
Write operation. This command must not be interrupted by any other commands.
( RAS = "H", CAS = "L", WE = "H", BA0, BA1 = Bank, A10 = "L", A0 to A8 = Column Address)
The Read command performs a Read operation to the bank designated by BA. The read data are
synchronized with both edges of DQS. The length of read data (Burst Length), Addressing Mode
and CAS Latency (access time from CAS command in a clock cycle) must be programmed in the
Mode Register at power-up prior to the Read operation.
( RAS = "H", CAS = ”L”, WE = ”H”, BA0, BA1 = Bank, A10 = ”H”, A0 to A8 = Column Address)
The Read with Auto-precharge command automatically performs the Precharge operation after the
Read operation.
Command Function
RAS (max)
Bank Activate Command
Bank Precharge Command
Precharge All Command
Write Command
Write with Auto-precharge Command
Read Command
Read with Auto-precharge Command
. After this command is issued, Read or Write operation can be executed.
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Publication Release Date: Oct. 08, 2010
W9425G6JB
Revision A01