CMOS SDRAM Samsung Electronics, CMOS SDRAM Datasheet - Page 16

• Manufacturer Part Number: CMOS SDRAM
• Description: CMOS SDRAM Device Operations
• Manufacturer: Samsung Electronics

DEVICE OPERATIONS
FUNCTION TRUTH TABLE (TABLE 1)
Refreshing
Accessing
Activating
Abbreviations : RA = Row Address
Register
Current
State
Mode
*Note : 1. All entries assume the CKE was active (High) during the precharge clock and the current clock cycle.
Row
2. Illegal to bank in specified state ; Function may be Iegal in the bank indicated by BA, depending on the
3. Must satisfy bus contention, bus turn around, and/or write recovery requirements.
4. NOP to bank precharging or in idle state. May precharge bank indicated by BA (and A
5. Illegal if any bank is not idle.
state of that bank.
CS
H
H
H
ELECTRONICS
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
NOP = No Operation Command
RAS
H
H
H
H
H
H
H
H
L
X
L
L
L
X
L
L
X
L
CAS
H
H
H
H
H
H
H
H
L
X
L
L
X
L
L
X
L
X
WE
H
H
H
X
X
L
X
L
X
X
X
X
X
X
X
L
X
X
CA = Column Address
BA = Bank Address
BA
BA
BA
BA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
A
ADDR
10
CA
RA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
/AP
ILLEGAL
NOP --> Row Active after t
NOP --> Row Active after t
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
NOP --> Idle after t
NOP --> Idle after t
ILLEGAL
ILLEGAL
ILLEGAL
NOP --> Idle after 2 clocks
NOP --> Idle after 2 clocks
ILLEGAL
ILLEGAL
ILLEGAL
AP = Auto Precharge
10
/AP).
RC
RC
ACTION
RCD
RCD
Rev. 0.2 Sep. 1999
CMOS SDRAM
Note
2
2
2
2