ESMT
M14D5121632A (2H)
Operation Temperature Condition (TC) -40°C~95°C
Read with Auto Precharge
If A10 is HIGH when a Read command is issued, the Read with Auto Precharge function is engaged. The device starts an Auto
Precharge operation on the rising edge which is (AL + BL/2) cycles later than the Read with AP command if tRAS (min) and tRTP(min)
are satisfied.
If tRAS(min) is not satisfied at the edge, the start point of Auto Precharge operation will be delayed until tRAS(min) is satisfied.
If tRTP (min) is not satisfied at the edge, the start point of Auto Precharge operation will be delayed until tRTP (min) is satisfied.
In case the internal precharge is pushed out by tRTP, tRP starts at the point where the internal precharge happens (not at the next
rising clock edge after this event). So for BL = 4, the minimum time from Read_AP to the next Bank Active command becomes AL +
(tRTP + tRP)*. For BL = 8, the time from Read_AP to the next Bank Active command is AL + 2 + (tRTP + tRP)*. (Note: “*” means
“rouded up to the next integer”).
< RL= 4 (AL= 1; CL= 3) >
T4
T0
T1
T2
T5
T6
T7
T8
T3
CLK
CLK
Bank A
Active
Posted CAS
READ A
Autoprecharge
CMD
NOP
NOP
NOP
NOP
NOP
NOP
NOP
AL+BL/2 clks
> = tRP
BL = 8
RTP <= 2 clocks
DQS,DQS
t
AL = 1
CL = 3
RL = 4
DQs
DoutA0
DoutA2
DoutA1
DoutA3 DoutA4 DoutA5
DoutA6
DoutA7
>= tRTP
RTP
t
Precharge begins here
Bank A
Active
Posted CAS
READ A
Autoprecharge
CMD
NOP
NOP
NOP
NOP
NOP
NOP
NOP
>=AL+tRTP+
t
RP
BL = 4
RTP > 2 clocks
DQS,DQS
t
AL = 1
CL = 3
RL = 4
DQs
DoutA0
DoutA2
DoutA1
DoutA3
t
RTP
t
RP
Precharge begins here
A new Bank Active command may be issued to the same bank if the following two conditions are satisfied simultaneously.
(1) The Precharge time (tRP) has been satisfied from the clock at which the Auto Precharge begins.
(2) The RAS cycle time (tRC) from the previous bank activation has been satisfied.
Elite Semiconductor Memory Technology Inc.
Publication Date : Aug. 2011
Revision : 1.1 48/62
ESMT [ ELITE SEMICONDUCTOR MEMORY TECHNOLOGY INC. ]
