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AS4LC2M8S1

AS4LC1M16S1

5/21/01; v.1.1

Alliance Semiconductor

P. 15 of 29

Mode register set command waveform

MRS can be issued only when both banks are idle.

Precharge waveforms

command without losing any burst data is show below.

(normal write; BL = 4)

(normal read; BL = 4)

Auto precharge waveforms

A10 controls the selection of auto precharge during the read or write command cycle.

(write with auto precharge; BL = 4)

(read with auto precharge; BL = 4)

*The row active command of the precharge bank can be issued after tRP from this point. The new read/write command of another activated bank can be

issued from this point. At burst read/write with auto precharge, CAS interrupt of the same/another bank is illegal.

CLK

CMD

PRE

MRS

ACT

Or Auto Refresh

CLK

CMD

DQ

WE

PRE

CLK

CMD

DQ(CL1)

DQ(CL2)

DQ(CL3)

Read data

PRE

CLK

CMD

DQ

WE

Auto precharge starts*

Auto precharge starts*

CLK

CMD

DQ(CL1)

DQ(CL2)

DQ(CL3)

Read data