tc59lm814cft TOSHIBA Semiconductor CORPORATION, tc59lm814cft Datasheet - Page 29

• Manufacturer Part Number: tc59lm814cft
• Description: 4,194,304 / 8,388,608-words X 4 Banks X 16 / 8-bits Network Fcram
• Manufacturer: TOSHIBA Semiconductor CORPORATION

AUTO-REFRESH TIMING (CL = 3, BL = 4)
Command
(output)
(output)
DQS
CLK
CLK
CLK
DQ
Note: In case of CL = 3, I
WRA REF
Hi-Z
Hi-Z
RDA
I
When the Auto-Refresh operation is performed, the synthetic average interval of Auto-Refresh
command specified by t
t
t
than Read / Write operation.
RCD
REFI
REFI
0
= 1 cycle
t
is average interval time in 8 Refresh cycles that is sampled randomly.
is specified to avoid partly concentrated current of Refresh operation that is activated larger area
1
t
REFI
LAL
1
WRA REF
=
Total time of 8 Refresh cycle
I
RC
2
REFC
= 5 cycles
I
RAS
CL = 3
t
REFI
2
must be meet 15 clock cycles.
= 4 cycles
DESL
3
8
must be satisfied.
WRA REF
8 Refresh cycle
4
Q0
t
3
Q1
WRA
5
=
I
RCD
Q2 Q3
t
1
+ t
= 1 cycle
REF
2
6
+ t
TC59LM814/06CFT-50,-55,-60
3
+ t
Hi-Z
Hi-Z
t
4
7
8
+ t
7
WRA REF
5
I
REFC
+ t
6
n − 1
+ t
DESL
= 15 cycles
7
+ t
t
8
8
n
2002-08-19 29/38
WRA REF
n + 1
WRA
RDA
or
MRS or
LAL or
n + 2
REF