W9425G8DH
8M × 4 BANKS × 8 BITS DDR SDRAM
Table of Contents-
1. GENERAL DESCRIPTION.............................................................................................................. 4
2. FEATURES...................................................................................................................................... 4
3. KEY PARAMETERS........................................................................................................................ 5
4. PIN CONFIGURATION.................................................................................................................... 6
5. PIN DESCRIPTION ......................................................................................................................... 7
6. BLOCK DIAGRAM........................................................................................................................... 8
7. FUNCTIONAL DESCRIPTION........................................................................................................ 9
7.1 Power Up Sequence.............................................................................................................. 9
7.2 Command Function ............................................................................................................... 9
7.2.1
7.2.2
7.2.3
7.2.4
7.2.5
7.2.6
7.2.7
7.2.8
7.2.9
Bank Activate Command........................................................................................................9
Bank Precharge Command ....................................................................................................9
Precharge All Command ........................................................................................................9
Write Command .....................................................................................................................9
Write with Auto-precharge Command ..................................................................................10
Read Command ...................................................................................................................10
Read with Auto-precharge Command ..................................................................................10
Mode Register Set Command ..............................................................................................10
Extended Mode Register Set Command ..............................................................................10
7.2.10 No-Operation Command ......................................................................................................10
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...............................................................................................11
7.2.15 Self Refresh Exit Command .................................................................................................11
7.2.16 Data Write Enable /Disable Command.................................................................................12
7.3 Read Operation ................................................................................................................... 12
7.4 Write Operation ................................................................................................................... 12
7.5 Precharge............................................................................................................................ 12
7.6 Burst Termination ................................................................................................................ 13
7.7 Refresh Operation ............................................................................................................... 13
7.8 Power Down Mode .............................................................................................................. 13
7.9 Input Clock Frequency Change during Precharge Power Down Mode .............................. 13
7.10 Mode Register Operation .................................................................................................... 14
7.10.1 Burst Length field (A2 to A0) ................................................................................................14
Publication Release Date: Nov. 20, 2007
- 1 -
Revision A4