K4R271669F Datasheet, PDF (17/20 Pages) Samsung semiconductor – 128Mbit RDRAM(F-die)

K4R271669F
Direct RDRAM^™
Timing Parameters
Table 13: Timing Parameter Summary
Min
Parameter
Description
-45
-800
t_RC
t_RAS
t_RP
t_PP
t_RR
t_RCD
t_CAC
t_CWD
t_CC
t_PACKET
t_RTR
t_OFFP
t_RDP
t_RTP
Row Cycle time of RDRAM banks -the interval between ROWA packets with ACT
28
commands to the same bank.
RAS-asserted time of RDRAM bank - the interval between ROWA packet with
ACT command and next ROWR packet with PRER^a command to the same bank.
20
Row Precharge time of RDRAM banks - the interval between ROWR packet with
PRER^a command and next ROWA packet with ACT command to the same bank.
8
Precharge-to-precharge time of RDRAM device - the interval between successive
ROWR packets with PRER^a commands to any banks of the same device.
8
RAS-to-RAS time of RDRAM device - the interval between successive ROWA
8
packets with ACT commands to any banks of the same device.
RAS-to-CAS Delay - the interval from ROWA packet with ACT command to
COLC packet with RD or WR command). Note - the RAS-to-CAS delay seen by
9
the RDRAM core (t_RCD-C) is equal to t_RCD-C = 1 + t_RCD because of differences in
the row and column paths through the RDRAM interface.
CAS Access delay - the interval from RD command to Q read data. The equation
8
for t_CAC is given in the TPARM register in Figure 40.
CAS Write Delay (interval from WR command to D write data.
6
CAS-to-CAS time of RDRAM bank - the interval between successive COLC com-
4
mands).
Length of ROWA, ROWR, COLC, COLM or COLX packet.
4
Interval from COLC packet with WR command to COLC packet which causes
8
retire, and to COLM packet with bytemask.
The interval (offset) from COLC packet with RDA command, or from COLC
packet with retire command (after WRA automatic precharge), or from COLC
packet with PREC command, or from COLX packet with PREX command to the
4
equivalent ROWR packet with PRER. The equation for t_OFFP is given in the
TPARM register in Figure 40.
Interval from last COLC packet with RD command to ROWR packet with PRER.
4
Interval from last COLC packet with automatic retire command to ROWR packet
4
with PRER.
a. Or equivalent PREC or PREX command. See Figure 15.
b. This is a constraint imposed by the core, and is therefore in units of µs rather than t_CYCLE.
Max
-
64µs^b
-
-
-
-
12
6
-
4
-
4
-
-
Units
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
t_CYCLE
Figure(s)
Figure 16
Figure 17
Figure 16
Figure 17
Figure 16
Figure 17
Figure 13
Figure 14
Figure 16
Figure 17
Figure 5
Figure 40
Figure 5
Figure 16
Figure 17
Figure 3
Figure 18
Figure 15
Figure 40
Figure 16
Figure 17
Page 15
Version 1.41 Jan. 2004