AS4SD4M16(2001) 查看數據表（PDF） - Austin Semiconductor
零件编号
产品描述 (功能)
生产厂家
AS4SD4M16 Datasheet PDF : 50 Pages
| |||
Austin Semiconductor, Inc.
COMMANDS
Truth Table 1 provides a quick reference of available commands.
This is followed by a written description of each command.
Two additional Truth Tables appear following the Operation
section; these tables provide current state/next state informa-
tion.
SDRAM
AS4SD4M16
TRUTH TABLE 1- Commands and DMQ Operation
(Note: 1)
NAME (FUNCTION)
CS\
COMMAND INHIBIT (NOP)
H
NO OPERATION (NOP)
L
ACTIVE (select bank and activate row)
L
READ (select bank and column and start READ burst)
L
WRITE (select bank and column and start WRITE burst) L
BURST TERMINATE
L
PRECHARGE (deactivate row in bank or banks)
L
AUTO REFRESH or SELF REFRESH (enter self refresh
mode)
L
LOAD MODE REGISTER
L
Write Enable/Output Enable
-
Write Inhibit/Output High-Z
-
RAS\
X
H
L
H
H
H
L
L
L
-
-
CAS\
X
H
H
L
L
H
H
L
L
-
-
WE\ DQM
XX
HX
HX
HX
L
X
L
X
L
X
HX
L
X
-
L
-
H
ADDR DQs NOTES
X
X
X
X
Bank/Row X
3
Bank/Col X
4
Bank/Col Valid 4
X
Active
Code
X
5
X
X
6,7
OpCode X
2
-
Active 8
-
High-Z 8
NOTE:
1. CKE is HIGH for all commands shown except SELF REFRESH.
2. A0-A11 define the op-code written to the Mode Register.
3. A0-A11 provide row address, and BA0, BA1 determine which bank is made active.
4. A0-A7 (x16) provide column address; A10 HIGH enables the auto precharge feature (nonpersistent), while A10
LOW disables the auto precharge feature; BA0, BA1 determine which bank is being read from or written to.
5. A10 LOW: BA0, BA1 determine the bank being precharged. A10 HIGH: All banks precharged and BA0, BA1 are
“Don’t Care.”
6. This command is AUTO REFRESH if CKE is HIGH; SELF REFRESH if CKE is LOW.
7. Internal refresh counter controls row addressing; all inputs and I/Os are “Don’t Care” except for CKE.
8. Activates or deactivates the DQs during WRITEs (zero-clock delay) and READs (two-clock delay).
AS4SD4M16
Rev. 1.5 10/01
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
9
Share Link: 