W9425G6EH
4 M × 4 BANKS × 16 BITS DDR SDRAM
Table of Contents-
1.
2.
3.
4.
5.
6.
7.
GENERAL DESCRIPTION.............................................................................................................................4
FEATURES....................................................................................................................................................4
KEY PARAMETERS ......................................................................................................................................5
PIN CONFIGURATION ..................................................................................................................................6
PIN DESCRIPTION........................................................................................................................................7
BLOCK DIAGRAM .........................................................................................................................................8
FUNCTIONAL DESCRIPTION.......................................................................................................................9
7.1
7.2
Power Up Sequence ..........................................................................................................................9
Command Function..........................................................................................................................10
7.2.1 Bank Activate Command......................................................................................................10
7.2.2 Bank Precharge Command ..................................................................................................10
7.2.3 Precharge All Command ......................................................................................................10
7.2.4 Write Command ...................................................................................................................10
7.2.5 Write with Auto-precharge Command...................................................................................10
7.2.6 Read Command ...................................................................................................................10
7.2.7 Read with Auto-precharge Command ..................................................................................10
7.2.8 Mode Register Set Command ..............................................................................................11
7.2.9 Extended Mode Register Set Command ..............................................................................11
7.2.10 No-Operation Command ......................................................................................................11
7.2.11 Burst Read Stop Command..................................................................................................11
7.2.12 Device Deselect Command..................................................................................................11
7.2.13 Auto Refresh Command.......................................................................................................11
7.2.14 Self Refresh Entry Command...............................................................................................12
7.2.15 Self Refresh Exit Command .................................................................................................12
7.2.16 Data Write Enable /Disable Command.................................................................................12
7.3
7.4
7.5
7.6
7.7
7.8
7.9
Read Operation................................................................................................................................12
Write Operation ................................................................................................................................13
Precharge.........................................................................................................................................13
Burst Termination.............................................................................................................................13
Refresh Operation............................................................................................................................13
Power Down Mode...........................................................................................................................14
Input Clock Frequency Change during Precharge Power Down Mode ............................................14
7.10 Mode Register Operation .................................................................................................................14
7.10.1 Burst Length field (A2 to A0) ................................................................................................14
7.10.2 Addressing Mode Select (A3)...............................................................................................15
Publication Release Date:Dec. 03, 2008
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Revision A08