29

Rev 0.7

64Mb Low Power DDR SDRAM

Advanced

Functional Truth Table

ABBREVIATIONS :

H=High Level, L=Low level, X=Don’t Care

NOTE :

1. All entries assume that CKE was High during the preceding clock cycle and the current clock cycle.

2. ILLEGAL to bank in specified state ; function may be legal in the bank indicated by BA, depending on the state of that bank.

3. Must satisfy bus contention, bus turn around and write recovery requirements.

4. NOP to bank precharging or in idle sate. May precharge bank indicated by BA.

5. ILLEGAL if any bank is not idle.

6. Refer to “Read with Auto Precharge Timing Diagram” for detailed information.

7. Refer to “Write with Auto Precharge Timing Diagram” for detailed infotmation.

8. CKE Low to High transition will re-enable CK, CK and other inputs asynchronously. A minimum setup time must be satisfied before

issuing any command other than EXIT.

9. Power-Down and Self-Refresh and Deep Power Down Mode can be entered only from All Bank Idle state.

10. The Deep Power Down Mode is exited by asserting CKE high and full initialization is required after exting Deep Power Down

Mode.

ILLEGAL = Device operation and/or data integrity are not guaranteed.

Current State

CKEn-1

CKEn

CS

RAS

CAS

WE

Add

Action

SELF-

L

H

H

X

X

X

X

Exit Self-Refresh

L

H

L

H

H

H

X

Exit Self-Refresh

L

H

L

H

H

L

X

ILLEGAL

L

H

L

H

L

X

X

ILLEGAL

L

H

L

L

X

X

X

ILLEGAL

L

L

X

X

X

X

X

NOP(Maintain Self-Refresh)

POWER

DOWN

L

H

X

X

X

X

X

L

L

X

X

X

X

X

NOP(Maintain Power Down)

DEEP POWER

DOWN

L

H

H

X

X

X

X

L

L

X

X

X

X

X

NOP(Maintain Deep Power Down)

ALL BANKS

H

H

X

X

X

X

X

Refer to Function Truth Table

H

L

L

L

L

H

X

Enter Self-Refresh

H

L

H

X

X

X

X

Enter Power Down

H

L

L

H

H

H

X

Enter Power Down

H

L

L

H

H

L

X

ILLEGAL

H

L

L

H

L

X

X

ILLEGAL

H

L

L

L

X

X

X

ILLEGAL

L

X

X

X

X

X

X

Refer to Current State=Power Down

ANY STATE

other than

listed above

H

H

X

X

X

X

X

Refer to Function Truth Table