SDRAM
AS4SD4M16
Austin Semiconductor, Inc.
TABLE OF CONTENTS
Functional Block Diagram - 4 Meg x 16 ........................................ 4
Pin Descriptions ............................................................................. 5
Clock Suspend......................................................................... 22
Burst Read/Single Write ...........................................................22
Concurrent Auto Precharge ................................................. 23
Truth Table 2 (CKE) ......................................................................25
Truth Table 3 (Current State, Same Bank) ................................. 26
Truth Table 4 (Current State, Different Bank) ........................... 28
Functional Description ................................................................. 6
Initialization ............................................................................. 6
Register Definition ................................................................. 6
Mode Register ................................................................ 6 Absolute Maximum Ratings ........................................................ 30
Burst Length ................................................................... 6 DC Electrical Characteristics and Operating Conditions......... 30
Burst Type ....................................................................... 7 ICC Specifications and Conditions .............................................. 30
CAS Latency ................................................................... 8 Capacitance ..................................................................................... 31
Operating Mode ............................................................. 8 AC Electrical Characteristics (Timing Table) ............................31
Write Burst Mode .......................................................... 8
Commands ....................................................................................... 9 Timing Waveforms
Truth Table 1 (Commands and DQM Operation) ......................... 9
Command Inhibit .................................................................... 10
No Operation (NOP) .................................................................10
Load Mode Register ............................................................. 10
Active ....................................................................................... 10
Read .......................................................................................... 10
Write ......................................................................................... 10
Precharge ................................................................................. 10
Auto Precharge ...................................................................... 10
Burst Terminate ...................................................................... 11
Auto Refresh .......................................................................... 11
Self Refresh ............................................................................. 11
Operation ..................................................................................... 12
Bank/Row Activation ............................................................ 12
Reads ........................................................................................ 13
Writes ....................................................................................... 19
Precharge................................................................................... 21
Power-Down...............................................................................21
Initialize and Load Mode Register ..................................... 34
Power-Down Mode ................................................................ 35
Clock Suspend Mode ........................................................... 36
Auto Refresh Mode .............................................................. 37
Self Refresh Mode ................................................................. 38
Reads
Read - Without Auto Precharge ................................. 39
Read - With Auto Precharge ....................................... 40
Alternating Bank Read Accesses .............................. 41
Read - Full-Page Burst ......................................................... 42
Read - DQM Operation ................................................ 43
Writes
Write - Without Auto Precharge ................................ 44
Write - With Auto Precharge ...................................... 45
Alternating Bank Write Accesses .............................. 46
Write - Full-Page Burst ................................................. 47
Write - DQM Operation ............................................... 48
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
AS4SD4M16
Rev. 1.5 10/01
3
AUSTIN [ AUSTIN SEMICONDUCTOR ]
