IS42S16100E Datasheet, PDF (27/82 Pages) Integrated Silicon Solution, Inc – 512K Words x 16 Bits x 2 Banks 16Mb SYNCHRONOUS DYNAMIC RAM

IS42S16100E, IS45S16100E
Read With Auto-Precharge
The read with auto-precharge command first executes a
burst read operation and then puts the selected bank in
the precharged state automatically. After the precharge
completes, the bank goes to the idle state. Thus this
command performs a read command and a precharge
command in a single operation.
During this operation, the delay period (tpql) between the
last burst data output and the start of the precharge opera-
tion differs depending on the CAS latency setting.
When the CAS latency setting is two, the precharge opera-
tion starts on one clock cycle before the last burst data is
output (tpql = –1). When the CAS latency setting is
three, the precharge operation starts on two clock cycles
before the last burst data is output (tpql = –2). Therefore,
the selected bank can be made active after a delay of trp
from the start position of this precharge operation.
The selected bank must be set to the active state before
executing this command.
The auto-precharge function is invalid if the burst length
is set to full page.
CAS Latency
tpql
3
2
–2
–1
CLK
COMMAND READA 0
DQ
DOUT 0
DOUT 1
tPQL
DOUT 2 DOUT 3
ACT 0
READ WITH AUTO-PRECHARGE
PRECHARGE START
tRP
(BANK 0)
CAS latency = 2, burstlength = 4
CLK
COMMAND READA 0
DQ
READ WITH AUTO-PRECHARGE
(BANK 0)
CAS latency = 3, burstlength = 4
DOUT 0
DOUT 1
tPQL
DOUT 2
DOUT 3
PRECHARGE START
tRP
Integrated Silicon Solution, Inc. — www.issi.com
Rev.  D
08/24/09
ACT 0
27