MB81ES171625 Fujitsu Media Devices Limited, MB81ES171625 Datasheet - Page 18

• Manufacturer Part Number: MB81ES171625
• Description: SINGLE DATA RATE I/F FCRAM Consumer/Embedded Application Specific Memory for SiP
• Manufacturer: Fujitsu Media Devices Limited

18
MB81ES171625/173225-15-X
11. Full Column Burst and Burst Stop Command (BST)
12. Precharge and Precharge Option (PRE, PALL)
(3) Counter Operation of Sequential Mode and lnterleave Mode
Length
The full column burst is an option of burst length and available only at sequential mode of burst type. This full
column burst mode is repeatedly access to the same row. If burst mode reaches the end of column address,
then it wraps around to the first column address (
(READ) /write (WRIT) , precharge (PRE) , or burst stop (BST) commands. The selection of Auto-precharge
option is illegal during the full column burst operation.
BST command is applicable to terminate the burst operation. If BST command is asserted during the burst mode,
its operation is terminated immediately and the internal state moves to Bank Active.
When a read mode is interrupted by BST command, the output will be in High-Z.
For the detailed rule, please refer to “8. Read Interrupted by Burst Stop (Example @ BL = Full Column)” in
“ TIMING DIAGRAMS.”
When a write mode is interrupted by BST command, the data to be applied at the same time with BST command
will be ignored.
SDR I/F FCRAM memory core is the same as a conventional DRAM’s, requiring precharge and refresh opera-
tions. Precharge rewrites the bit line and reset the internal Row address line and is executed by the Precharge
command (PRE) . With the Precharge command, SDR I/F FCRAM will automatically be in standby state after
precharge time (t
The precharged bank is selected by combination of AP and BA when the Precharge command is asserted. If
AP
precharged (PRE) .
The auto-precharge enters precharge mode at the end of burst mode of read or write without the Precharge
command assertion.
This auto precharge is entered by AP High when a read or write command is asserted. Refer to “ FUNCTIONAL
TRUTH TABLE.”
Burst
2
4
8
High, all banks are precharged regardless of BA (PALL) . If AP
Starting Column Address
A
X
X
X
X
X
X
0
0
0
0
1
1
1
1
2
RP
) .
A
X
X
0
0
1
1
0
0
1
1
0
0
1
1
1
A
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
0
1
2
3
4
5
6
7
1
2
3
4
5
6
7
0
Sequential Mode
0) and continues to count until interrupted by the new read
0
1
2
3
2
3
4
5
6
7
0
1
0
1
1
2
3
0
3
4
5
6
7
0
1
2
1
0
2
3
0
1
4
5
6
7
0
1
2
3
3
0
1
2
5
6
7
0
1
2
3
4
6
7
0
1
2
3
4
5
4
5
6
7
0
1
2
3
Low, a bank to be selected by BA is
0
1
2
3
4
5
6
7
4
7
6
1
0
3
2
5
Interleave Mode
0
1
2
3
2
3
0
1
6
7
4
5
1
0
1
0
3
2
3
2
1
0
7
6
5
4
2
1
0
3
0
1
4
5
6
7
0
1
2
3
2
1
0
5
4
7
6
1
0
3
2
3
6
7
4
5
2
3
0
1
7
6
5
4
3
2
1
0