Datasheet

Burst Read Operation followed by a Precharge
The minimum external Read command to Precharge command spacing to the same bank is equal to AL + t
RTP
with t
RTP
being the Internal Read Command to Precharge Command Delay. Note that the minimum ACT to
PRE timing, t
RAS
, must be satisfied as well. The minimum value for the Internal Read Command to Precharge
Command Delay is given by t
RTP(min)
, A new bank active command may be issued to the same bank if the
following two conditions are satisfied simultaneously:
1. The minimum RAS precharge time (t
RP.MIN
) has been satisfied from the clock at which the precharge begins.
2. The minimum RAS cycle time (t
RC.MIN
) from the previous bank activation has been satisfied.
Examples of Read commands followed by Precharge are show in Read to Precharge with 1t
CK
Preamble to
Read to Precharge with Additive Latency and 1t
CK
Preamble.
DON'T CARE
NOTE 1. BL = 8, RL = 11(CL = 11 , AL = 0 ), Preamble = 1t
CK
, t
RTP
= 6, t
RP
= 11
NOTE 2. Dout n = data-out from column n.
NOTE 3. DES commands are shown for ease of illustration; other commands may be valid at these times.
NOTE 4. The example assumes t
RAS
. MIN is satisfied at Precharge command time(T7) and that t
RC
. MIN is satisfied at the next Active command time(T18).
NOTE 5. CA Parity = Disable, CS to CA Latency = Disable, Read DBI = Disable.
T0 T1 T2 T6 T7 T10 T11 T12
T13
T14
TRANSITIONING DATA
Dout
n
Dout
n+1
Dout
n+2
RL = AL + CL
CK#
CK
DQ
CMD
T15
READDES DES DES PRE DES DES DES DES DES DES
DES
Bank a
Col n
ADDR
ACT
T16 T18
Bank a
(or all)
DES
DES
T19 T20
Dout
n+3
t
RP
t
RTP
DES
T21
Dout
n
Dout
n+1
Dout
n+2
DQ
Dout
n+7
Dout
n+3
Dout
n+4
Dout
n+5
Dout
n+6
DQS, DQS#
DQS, DQS#
Bank a
Row b
BC4 Operation:
BC8 Operation:
Figure 111. READ to PRECHARGE with 1t
CK
Preamble
DON'T CARE
NOTE 1. BL = 8, RL = 11(CL = 11 , AL = 0 ), Preamble = 2t
CK
, t
RTP
= 6, t
RP
= 11
NOTE 2. Dout n = data-out from column n.
NOTE 3. DES commands are shown for ease of illustration; other commands may be valid at these times.
NOTE 4. The example assumes t
RAS
. MIN is satisfied at Precharge command time(T7) and that t
RC
. MIN is satisfied at the next Active command time(T18).
NOTE 5. CA Parity = Disable, CS to CA Latency = Disable, Read DBI = Disable.
T0 T1 T3 T7 T10 T11 T12 T13
T14
T15
TRANSITIONING DATA
t
RTP
Dout
n
Dout
n+1
Dout
n+2
Dout
n+3
RL = AL + CL
CK#
CK
DQ
CMD
T16
READDES DES PRE DES DES DES DES DES DES DES
DES
Bank a
Col n
ADDR
ACT
T17 T18
BG a
(or all)
DES
DES
T19 T20
DES
T21
t
RP
Bank a
Row b
BC4 Operation:
Dout
n
Dout
n+1
Dout
n+2
Dout
n+7
Dout
n+3
Dout
n+4
Dout
n+5
Dout
n+6
BC8 Operation:
DQ
DQS, DQS#
DQS, DQS#
Figure 112. READ to PRECHARGE with 2t
CK
Preamble
AS4C256M16D4
Confidential
- 105 of 201 -
Rev.1.0 Aug.2019