K4R761869A-F Datasheet, PDF (17/20 Pages) Samsung semiconductor – 576Mbit RDRAM (A-die) 1M x 18bit x 32s banks Direct RDRAMTM

K4R761869A
Direct RDRAM^™
Timing Parameters
Table 13: Timing Parameter Summary
Parameter
Description
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 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.
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.
Precharge-to-precharge time of RDRAM device - the interval
between successive ROWR packets with PRER^a commands to any
banks of the same device.
RAS-to-RAS time of RDRAM device - the interval between succes-
sive ROWA 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 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 for t_CAC is given in the TPARM register in Figure 40.
CAS Write Delay (interval from WR command to D write data.
CAS-to-CAS time of RDRAM bank - the interval between successive
COLC commands).
Length of ROWA, ROWR, COLC, COLM or COLX packet.
Interval from COLC packet with WR command to COLC packet
which causes 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 pre-
charge), or from COLC packet with PREC command, or from COLX
packet with PREX command to the 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.
Interval from last COLC packet with automatic retire command to
ROWR packet with PRER.
Min
-32
-1200
32
22
10
8
8
9
9
6
4
4
8
4
4
4
Min
-32P
-1066
28
20
8
8
8
9
8
6
4
4
8
4
4
4
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.
Min
-40
-800
28
20
Max Units Figure(s)
- t_CYCLE
64µs^b t_CYCLE
Figure 16
Figure 17
Figure 16
Figure 17
Figure 16
8
- t_{CYCLE Figure 17}
8
- t_CYCLE Figure 13
8
- t_CYCLE Figure 14
Figure 16
7
- t_{CYCLE Figure 17}
Figure 5
8
12 t_{CYCLE Figure 40}
6
6 t_CYCLE Figure 5
Figure 16
4
- t_{CYCLE Figure 17}
4
4 t_CYCLE Figure 3
8
- t_CYCLE Figure 18
Figure 15
4
4 t_{CYCLE Figure 40}
4
- t_CYCLE Figure 16
4
- t_CYCLE Figure 17
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Version 1.41 Jan. 2004