Datasheet

BA,Col n
BA a(or
all)
BA,Col b
WRITE PRE NOP
CK
CK
Command
Address
1) Dl b = Data in to column b.
2)
An interrupted burst of 4, 8 or 16 is shown, 2 data elements are written.
3) t
WR
is referenced from the positive clock edge after the last desired Data In pair.
4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
5) *1=can be Don't Care for programmed burst length of 4
6) *2=for programmed burst length of 4, DQS becomes Don't Care at this point
NOP NOP NOP
= Don't Care
DQS
DQ
DM
tDQSSmax
t
WR
DI b
*1*1*1*1
*2
7.7 Precharge
The PRECHARGE command (see Figure 32) is used to deactivate the open row in a particular bank or the open row in all banks.
The bank(s) will be available for a subsequent row access a specified time (tRP) after the PRECHARGE command is issued.
= Don't Care
(High)
CK
CK
CKE
CS
RAS
CAS
WE
Address
BA=BANK Address
(if A10 = L,otherwise Don't Care)
BABA0,BA1
A10
All Banks
One Bank
Input A10 determines whether one or all
banks are to be precharged. In case where only one bank is to be precharged, inputs BA0,
BA1 select the bank. Otherwise BA0, BA1 are treated as “Don’t Care”.
Once a bank has been precharged, it is in the
idle state and must be activated prior to any READ or WRITE command being issued.
A PRECHARGE command will be treated as a NOP if there is no open row in that bank, or if the previously open row is already in
the process of precharging.
AS4C32M16MD1A-5BCN
Confidential
- 35/56 -
Rev.1.2 July 2016
Figure 31 — Interrupting Write to Precharge
Figure 32 — Precharge command