Discontinued (12/98 - last order; 9/99 last ship)
IBM0316409C IBM0316809C IBM0316169C
IBM03164B9C
16Mb Synchronous DRAM-Die Revision D
Bank Activate Command
In relation to the operation of a fast page mode DRAM, the Bank Activate command corresponds to a falling
RAS signal. The Bank Activate command is issued by holding CAS and WE high with CS and RAS low at the
rising edge of the clock. The bank select address, A11 (sometimes referred to as BS), is used to select the
desired bank. If BS is low then bank A is activated, if BS is high then bank B is activated. The row address A0
- A10 is used to determine which row to activate in the selected bank. Only banks A and B within a single
deck of a 2-High stacked device can be accessed. Simultaneous operation of both decks in a stacked device
is not allowed, except during Self Refresh.
The Bank Activate command must be applied before any Read or Write operation can be executed. The
delay from when the Bank Activate command is applied to when the first read or write operation can begin
must meet or exceed the RAS to CAS delay time (tRCD). Once a bank has been activated it must be pre-
charged before another Bank Activate command can be applied to the same bank. The minimum time inter-
val between successive Bank Activate commands to the same bank is determined by the RAS cycle time of
the device (tRC). The minimum time interval between interleaved Bank Activate commands (Bank A to Bank B
and vice versa) is the Bank to Bank delay time (tRRD).
Bank Activate Command Cycle (CAS Latency = 3, t
= 3)
RCD
T0
T1
T2
T3
Tn
Tn+1
Tn+2
Tn+3
CLK
. . . . . . . . . .
Bank A
Col. Addr.
Bank A
Row Addr.
Bank B
Row Addr.
Bank A
Row Addr.
. . . . . . . . . .
ADDRESS
RAS-CAS delay (tRCD
)
RAS - RAS delay time (tRRD
)
Write A
with Auto-
Precharge
Bank B
NOP
Bank A
Activate
Bank A
Activate
. . . . . . . . . .
NOP
NOP
NOP
COMMAND
Activate
RAS Cycle time (tRC
)
: “H” or “L”
©IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
08J3348.E35853
5/98
Page 13 of 120
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