K4Y50164UC Datasheet, PDF (18/76 Pages) Samsung semiconductor – 512Mbit XDR TM DRAM(C-die)

K4Y50164UC
K4Y50084UC
K4Y50044UC
K4Y50024UC
XDR^TM DRAM
The first request is shown along the vertical axis on the left of the table. The second request is shown along the horizontal axis at the top
of the table. Each request includes a bank specification “Ba” and “Bb”. The first and second banks may be the same, or they may be
different. These two subcases for each interaction are shown along the vertical axis on the letf.
There are 32 possible interaction cases altogether. The table gives each case a label of the form “xyz”, where “x” and “y” are one of the
four operation types(“A” for Activate, “R” for Read, “W” for Write, or “P” for Precharge) for the first and second request, respectively, and
“z” indicates the same bank(“s”) or different bank(“d”).
Along the horizontal axis at the bottom of the table are cross references to four figures(Figure4 through Figure7). Each figure illustrates
the eight cases in the corresponding vertical column. Thus, Figure4 shows the eight cases when the second request is an activate oper-
ation(“A”). In the following discussion of the cases, only those in which the interaction interval is greater than t_CYCLE will be described.
7.4 Request Interactions Cases
In Figure4. the interaction interval for the AAd case is t_RR. This parameter is the row-to-row time and is the minimum interval between
activate commands to different banks of a device.
The interaction interval for the AAs case is t_RC. This is the row cycle time parameter and is the minimum interval between activate
commands to same banks of a device. A precharge operation must be inserted between the two activate operations.
The interaction interval for the RAs case is t_RDP + t_RP. A precharge operation must be inserted between the read and activate operation.
The minimum interval between a read and a precharge operation to a bank is t_RDP. The minimum interval between a precharge and an
activate operation to a bank is t_RP.
The interaction interval for the WAs case is t_WDP + t_RP. A precharge operation must be inserted between the read and the activate oper-
ation. The minimum interval between a write and a precharge operation to a bank is t_WDP. The minimum interval between a precharge
and an activate operation to a bank is t_RP.
The interaction interval for the PAs case is t_RP. The minimum interval between a precharge and an activate operation to a bank is t_RP.
In Figure5, the interaction interval for the ARs case is t_RCD-R. This is the row-to-column-read time parameter and represents the
minimum interval between an activate operation and a read operation to a bank.
The interaction interval for the RRd and RRs cases is t_CC. This is the column-to-column time parameter and represents the minimum
interval between two read operations.
The interaction interval for the WRd and WRs cases is t_∆WR. This is the write-to-read time parameter and represents the minimum
interval between a write and a read operation to any banks. See “Read/Write Interaction” on page 31.
The interaction interval for the PRs case is t_RP + t_RCD-R. An activate operation must be inserted between the precharge and the read
operation. The minimum interval between a precharge and an activate operation to a bank is t_RP. The minimum interval between an acti-
vate and a read operation to a bank is t_RCD-R.
In Figure6. the interaction interval for the AWs case is t_RCD-W. This is the row-to-column-write timing parameter and represents the
minimum interval between an activate operation and a write operation to a bank.
The interaction interval for the RWd and RWs cases is t_∆RW. This is the read-to-write time parameter and represents the minimum
interval between a read and a write operation to any banks. See “Read/Write Interaction” on page 31.
The interaction interval for the WWd and WWs cases is t_CC. This is the column-to-column time parameter and represents the minimum
interval between two write operations.
The interaction interval for the PWs case is t_RP + t_RCD-W. An activate operation must be inserted between the precharge and the write
operation. The minimum interval between a precharge and an activate operation to a bank is t_RP. The minimum interval between an acti-
vate and a write operation to a bank is t_RCD-W.
In Figure7, the interaction interval for the APs case is t_RAS. This parameter is the minimum activate-to-precharge time to a bank.
The interaction interval for the RPs and WPs cases are t_RDP and t_WDP, respectively. These are the read-or write-to-precharge time
parameters to a bank.
Ths interaction interval for the PPd case is t_PP. This parameter is the precharge-to-precharge time and the minimum interval between
precharge commands to different banks of a device.
The interaction interval for the PPs case is t_RC. This is the row cycle time parameter and the minimum interval between precharge
commands to same banks of a device. An activate operation must be inserted between the two activate operations. This activate opera-
tion must be placed a time t_RP after the first, and a time t_RAS before the second precharge.
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Rev. 1.1 August 2006