eorex

Preliminary

EM488M1644LBB

May. 2007

www.eorex.com

The normal drive strength got all outputs is specified to be LV-CMOS. By setting EMRS specific parameter

on A6 and A5, driving capability of data output drivers is selected.

Partial Array Self Refresh

In EMRS setting ,memory array size to be refreshed during self-refresh operation is programmable in order

to reduce power. Data outside the defined area will not be retained during self-refresh.

1. Command Truth Table

CKE

Command

Symbol

n-1

n

/CS

/RAS

/CAS

/WE

BA0,

BA1

A10

A11,

A9~A10

Ignore Command

DESL

H

X

H

X

X

X

X

X

X

No Operation

NOP

H

X

L

H

H

H

X

X

X

Burst Stop

BSTH

H

X

L

H

H

L

X

X

X

Read

READ

H

X

L

H

L

H

V

L

V

Read with Auto Pre-charge

READA

H

X

L

H

L

H

V

H

V

Write

WRIT

H

X

L

H

L

L

V

L

V

Write with Auto Pre-charge

WRITA

H

X

L

L

H

H

V

H

V

Bank Activate

ACT

H

X

L

L

H

H

V

V

V

Pre-charge Select Bank

PRE

H

X

L

L

H

L

V

L

X

Pre-charge All Banks

PALL

H

X

L

L

H

L

X

H

X

Mode Register Set

MRS

H

X

L

L

L

L

L

L

V

H = High level, L = Low level, X = High or Low level (Don't care), V = Valid data input

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