CMOS SDRAM Samsung Electronics, CMOS SDRAM Datasheet - Page 15

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

DEVICE OPERATIONS
FUNCTION TRUTH TABLE (TABLE 1)
Precharge
Precharge
Read with
Write with
charging
Current
Active
Read
Write
State
IDLE
Row
Auto
Auto
Pre-
CS
H
H
H
H
H
H
H
ELECTRONICS
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
RAS
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
X
L
L
L
L
X
L
L
L
X
L
L
L
X
L
L
L
X
L
L
X
L
L
X
L
L
CAS
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
X
L
L
L
X
L
L
L
X
L
L
L
X
L
L
L
X
L
L
X
L
L
X
L
WE
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
X
L
X
L
L
X
L
L
L
X
X
L
L
L
X
X
L
L
L
X
X
L
X
X
X
X
L
X
X
X
X
L
X
L
OP code
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
BA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
CA, A
CA, A
CA, A
CA, A
CA, A
CA, A
CA, A
CA, A
CA, A
RA, RA
RA, RA
OP code
A
A
A
A
A
ADDR
10
10
10
10
10
RA
RA
RA
RA
CA
RA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
/AP
/AP
/AP
/AP
/AP
10
10
10
10
10
10
10
10
10
/AP
/AP
/AP
/AP
/AP
/AP
/AP
/AP
/AP
10
10
NOP
NOP
ILLEGAL
ILLEGAL
Row (& Bank) Active ; Latch RA
NOP
Auto Refresh or Self Refresh
Mode Register Access
NOP
NOP
ILLEGAL
Begin Read ; latch CA ; determine AP
Begin Write ; latch CA ; determine AP
ILLEGAL
Precharge
ILLEGAL
NOP (Continue Burst to End --> Row Active)
NOP (Continue Burst to End --> Row Active)
Term burst --> Row active
Term burst, New Read, Determine AP
Term burst, New Write, Determine AP
ILLEGAL
Term burst, Precharge timing for Reads
ILLEGAL
NOP (Continue Burst to End --> Row Active)
NOP (Continue Burst to End --> Row Active)
Term burst --> Row active
Term burst, New read, Determine AP
Term burst, New Write, Determine AP
ILLEGAL
Term burst, precharge timing for Writes
ILLEGAL
NOP (Continue Burst to End --> Precharge)
NOP (Continue Burst to End --> Precharge)
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
NOP (Continue Burst to End --> Precharge)
NOP (Continue Burst to End --> Precharge)
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
NOP --> Idle after t
NOP --> Idle after t
ILLEGAL
ILLEGAL
ILLEGAL
NOP --> Idle after t
RP
RP
RP
ACTION
Rev. 0.2 Sep. 1999
CMOS SDRAM
Note
2
2
4
5
5
2
2
3
2
3
3
2
3
2
2
2
2
2
4