PRELIMINARY
256Mb: x32
SDRAM
TABLE OF CONTENTS
Functional Block Diagram - 8 Meg x 32 .................
Pin Descriptions ...........................................................
Functional Description
..........................................
Initialization ...........................................................
Register Definition .................................................
Mode Register ...................................................
Burst Length ................................................
Burst Type ....................................................
CAS Latency ................................................
Operating Mode .........................................
Write Burst Mode .......................................
Commands
..................................................................
Truth Table 1 (Commands and DQM Operation)
...........
Command Inhibit .................................................
No Operation (NOP) ............................................
Load Mode Register ...............................................
Active .......................................................................
Read .......................................................................
Write .......................................................................
Precharge .................................................................
Auto Precharge .......................................................
Burst Terminate ......................................................
Auto Refresh ...........................................................
Self Refresh ..............................................................
Operation
....................................................................
Bank/Row Activation ...........................................
Reads .......................................................................
Writes .......................................................................
Precharge .................................................................
Power-Down ..........................................................
Clock Suspend ........................................................
Burst Read/Single Write ........................................
Concurrent Auto Precharge .................................
Write With Auto Precharge .................................
5
6
9
9
9
9
9
10
11
11
11
12
12
13
13
13
13
13
13
13
13
14
14
14
15
15
16
22
24
24
25
25
26
27
28
29
31
Absolute Maximum Ratings ...................................... 33
DC Electrical Characteristics
and Operating Conditions ......................................... 33
I
DD
Specifications and Conditions ........................... 33
Capacitance .................................................................. 34
AC Electrical Characteristics
(Timing Table) ..... 34
AC Functional Characteristics ............................
35
Timing Waveforms
Initialize and Load Mode Register ......................
Power-Down Mode ...............................................
Clock Suspend Mode ............................................
Auto Refresh Mode ...............................................
Self Refresh Mode ..................................................
Reads
Read – Single Read ...........................................
Read – Without Auto Precharge ...................
Read – With Auto Precharge ..........................
Alternating Bank Read Accesses .....................
Read – Full-Page Burst .....................................
Read – DQM Operation .................................
Writes
Write – Single Write .........................................
Write – Without Auto Precharge ..................
Write – With Auto Precharge ........................
Alternating Bank Write Accesses ...................
Write – Full-Page Burst ....................................
Write – DQM Operation ................................
Package
86-Pin TSOP ......................................................
90-Ball FBGA ....................................................
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
Truth Table 2 (CKE)
.....................................................
Truth Table 3 (Current State, Same Bank)
......................
Truth Table 4 (Current State, Different Bank)
.................
09005aef80cd8e48
256MbSDRAMx32.p65 – Rev. B; Pub. 03/04
4
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©2003 Micron Technology, Inc.
MICRON [ MICRON TECHNOLOGY ]
