W949D6DB Datasheet, PDF (20/60 Pages) Winbond – Standard Self Refresh Mode

W949D6DB / W949D2DB
7.6 Commands
All commands (address and control signals) are registered on the positive edge of clock (crossing of CK
going high and CK going low).
7.6.1 Basic Timing Parameters for Commands
t_CK
t_CH
t_CL
CK
CK
t_IS t_IH
Input
Valid
Valid
Valid
= Don't Care
NOTE: Input = A0–An, BA, CKE, CS, RAS, CAS, WE
7.6.2 Truth Table – Commands
NAME (FUNCTION)
CS RAS CAS WE ^{BA A10/AP ADDR NOTES}
DESELECT (NOP)
HX XX
X
X
X
2
NO OPERATION (NOP)
L
H
HH
X
X
X
2
ACTIVE (Select Bank and activate row)
L
L
H
H Valid Row
Row
READ (Select bank and column and start read burst) L
H
L
H Valid
L
Col
READ with AP (Read Burst with Auto Precharge)
L
H
L
H Valid
H
Col
3
WRITE (Select bank and column and start write burst) L
H
L
L Valid
L
Col
WRITE with AP (Write Burst with Auto Precharge)
L
H
L
L Valid
H
Col
3
BURST TERMINATE
LHHL
X
X
X
4, 5
PRECHARGE (Deactivate row in selected bank)
L
L
H
L Valid
L
X
6
PRECHARGE ALL (Deactivate rows in all banks)
L
L
H
L
X
H
X
6
AUTO REFRESH or enter SELF REFRESH
L
L
L
H
X
X
X 7, 8, 9
MODE REGISTER SET
L
L
L
L Valid
Op-code
10
Notes:
1. All states and sequences not shown are illegal or reserved.
2. DESELECT and NOP are functionally interchangeable.
3. Auto precharge is non-persistent. A10 High enables Auto precharge, while A10 Low disables Auto precharge.
4. Burst Terminate applies to only Read bursts with Auto precharge disabled. This command is undefined and should not be used
for Read with Auto precharge enabled, and for Write bursts.
5. This command is BURST TERMINATE if CKE is High and DEEP POWER DOWN entry if CKE is Low.
6. If A10 is low, bank address determines which bank is to be precharged. If A10 is high, all banks are precharged and BA0~BA1
are don’t care.
7. This command is AUTO REFRESH if CKE is High and SELF REFRESH if CKE is low.
8. All address inputs and I/O are ‘don’t care’ except for CKE. Internal refresh counters control bank and row addressing.
9. All banks must be precharged before issuing an AUTO-REFRESH or SELF REFRESH command.
10. BA0 and BA1 value select between MRS and EMRS.
11. CKE is HIGH for all commands shown except SELF REFRESH and DEEP POWER-DOWN.
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Publication Release Date: Oct. 08, 2014
Revision: A01-003