Integrated Silicon Solution, Inc. — www.issi.com —
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11
PRELIMINARY INFORMATION Rev. 00J
03/03/09
IS42S32400B
Current State
CSCS
CSCS
CS
RAS RAS
RAS RAS
RAS
CASCAS
CASCAS
CAS
WE WE
WE WE
WE Address Command Action
Write Recovering H × × × × DESL Nop, Enter row active after tDPL
L H H H × NOP Nop, Enter row active after tDPL
L H H L × BST Nop, Enter row active after tDPL
L H L H BA, CA, A10 READ/READA Begin read
(8)
L H L L BA, CA, A10 WRIT/ WRITA Begin new write
L L H H BA, RA ACT ILLEGAL
(3)
L L H L BA, A10 PRE/PALL ILLEGAL
(3)
L L L H × REF/SELF ILLEGAL
L L L L OC, BA MRS ILLEGAL
Write Recovering H × × × × DESL Nop, Enter precharge after tDPL
with Auto L H H H × NOP Nop, Enter precharge after tDPL
Precharge L H H L × BST Nop, Enter row active after tDPL
L H L H BA, CA, A10 READ/READA ILLEGAL
(3,8,11)
L H L L BA, CA, A10 WRIT/WRITA ILLEGAL
(3,11)
L L H H BA, RA ACT ILLEGAL
(3,11)
L L H L BA, A10 PRE/PALL ILLEGAL
(3,11)
L L L H × REF/SELF ILLEGAL
L L L L OC, BA MRS ILLEGAL
Refresh H × × × × DESL Nop, Enter idle after tRC
L H H × × NOP/BST Nop, Enter idle after tRC
L H L H BA, CA, A10 READ/READA ILLEGAL
L H L L BA, CA, A10 WRIT/WRITA ILLEGAL
L L H H BA, RA ACT ILLEGAL
L L H L BA, A10 PRE/PALL ILLEGAL
L L L H × REF/SELF ILLEGAL
L L L L OC, BA MRS ILLEGAL
Mode Register H × × × × DESL Nop, Enter idle after 2 clocks
Accessing L H H H × NOP Nop, Enter idle after 2 clocks
L H H L × BST ILLEGAL
L H L × BA, CA, A10 READ/WRITE ILLEGAL
L L × × BA, RA ACT/PRE/PALL ILLEGAL
REF/MRS
FUNCTIONAL TRUTH TABLE Continued:
Note: H=VIH, L=VIL x= VIH or VIL, V = Valid Data, BA= Bank Address, CA+Column Address, RA=Row Address, OC= Op-Code
Notes:
1. All entries assume that CKE is active (CKEn-1=CKEn=H).
2. If both banks are idle, and CKE is inactive (Low), the device will enter Power Down mode. All input buffers except CKE will
be disabled.
3. Illegal to bank in specified states; Function may be legal in the bank indicated by Bank Address (BA), depending on the
state of that bank.
4. If both banks are idle, and CKE is inactive (Low), the device will enter Self-Refresh mode. All input buffers except CKE will
be disabled.
5. Illegal if tRCD is not satisfied.
6. Illegal if tRAS is not satisfied.
7. Must satisfy burst interrupt condition.
8. Must satisfy bus contention, bus turn around, and/or write recovery requirements.
9. Must mask preceding data which don’t satisfy tDPL.
10. Illegal if tRRD is not satisfied.
11. Illegal for single bank, but legal for other banks.