K4G323222A Datasheet, PDF (10/49 Pages) Samsung semiconductor – 32Mbit SGRAM

K4G323222A
SIMPLIFIED TRUTH TABLE
CMOS SGRAM
3. Auto refresh functions as same as CBR refresh of DRAM.
The automatical precharge without Row precharge command is meant by "Auto".
Auto/Self refresh can be issued only at both precharge state.
4. BA : Bank select address.
If "Low" at read, (block) write, Row active and precharge, bank A is selected.
If "High" at read, (block) write, Row active and precharge, bank B is selected.
If A8 is "High" at Row precharge, BA is ignored and both banks are selected.
5. During burst read or write with auto precharge, new read/(block) write command cannot be issued.
Another bank read/(block) write command can be issued at tRP after the end of burst.
6. Burst stop command is valid only at full page burst length.
7. DQM sampled at positive going edge of a CLK.
masks the data-in at the very CLK(Write DQM latency is 0)
but makes Hi-Z state the data-out of 2 CLK cycles after.(Read DQM latency is 2)
8. Graphic features added to SDRAM′s original features.
If DSF is tied to low, graphic functions are disabled and chip operates as a 32M SDRAM with 32 DQ′s.
SGRAM vs SDRAM
Function
DSF
SGRAM
Function
L
MRS
MRS
H
SMRS
Write
L
Normal
Write
H
Block
Write
If DSF is low, SGRAM functionality is identical to SDRAM functionality.
SGRAM can be used as an unified memory by the appropriate DSF control
--> SGRAM=Graphic Memory + Main Memory
Rev. 1.3 (Dec. 2000)
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