HYB25D256800CE Datasheet, PDF (17/39 Pages) Qimonda AG – 256-Mbit Double-Data-Rate SDRAM

Internet Data Sheet
HY[B/I]25D256[16/40/80]0C[E/C/F/T](L)
256 Mbit Double-Data-Rate SDRAM
TABLE 10
Truth Table 1a: Commands
Name (Function)
CS RAS CAS WE Address MNE Note
Deselect (NOP)
H X X XX
NOP
1)2)
No Operation (NOP)
L H H HX
NOP
1)2)
Active (Select Bank And Activate Row)
LL
H
H Bank/Row ACT
1)3)
Read (Select Bank And Column, And Start Read Burst)
LH
L
H Bank/Col Read ¹⁾⁴⁾
Write (Select Bank And Column, And Start Write Burst)
LH
L
L Bank/Col Write ¹⁾⁴⁾
Burst Terminate
L H H LX
BST
1)5)
Precharge (Deactivate Row In Bank Or Banks)
LL
H L Code
PRE
1)6)
Auto Refresh Or Self Refresh (Enter Self Refresh Mode)
LL
L
HX
AR/SR ¹⁾⁷⁾⁸⁾
Mode Register Set
LL
L
L Op-Code MRS
1)9)
1) CKE is HIGH for all commands shown except Self Refresh.V_REF must be maintained during Self Refresh operation
2) Deselect and NOP are functionally interchangeable.
3) BA0-BA1 provide bank address and A0-A12 provide row address.
4) BA0, BA1 provide bank address; A0-Ai provide column address (where i = 8 for x16, i = 9 for x8 and 9, 11 for x4); A10 HIGH enables the
Auto Precharge feature (nonpersistent), A10 LOW disables the Auto Precharge feature.
5) Applies only to read bursts with Auto Precharge disabled; this command is undefined (and should not be used) for read bursts with Auto
Precharge enabled or for write bursts.
6) A10 LOW: BA0, BA1 determine which bank is precharged. A10 HIGH: all banks are precharged and BA0, BA1 are “Don’t Care”.
7) This command is Auto Refresh if CKE is HIGH; Self Refresh if CKE is LOW.
8) Internal refresh counter controls row and bank addressing; all inputs and I/Os are “Don’t Care” except for CKE.
9) BA0, BA1 select either the Base or the Extended Mode Register (BA0 = 0, BA1 = 0 selects Mode Register; BA0 = 1, BA1 = 0 selects
Extended Mode Register; other combinations of BA0-BA1 are reserved; A0-A12 provide the op-code to be written to the selected Mode
Register).
Name (Function)
Write Enable
Write Inhibit
1) Used to mask write data; provided coincident with the corresponding data.
TABLE 11
Truth Table 1b: DM Operation
DM
DQs Note
L
Valid ¹⁾
H
X
1)
Rev. 2.3, 2007-03
17
03062006-8CCM-VPUW