44
Integrated Silicon Solution, Inc. — www.issi.com
Rev. F
03/03/09
IS42S32400D
DON'T CARE
CLK
CKE
COMMAND
ADDRESS
DQ
T0 T1 T2 T3 T4 T5
NOP
WRITE
NOP NOP
BANK a,
COL n
DIN n
DIN n+1 DIN n+2
INTERNAL
CLOCK
DON'T CARE
CLK
CKE
COMMAND
ADDRESS
DQ
T0 T1 T2 T3 T4 T5 T6
READ
NOP NOP NOP NOP NOP
BANK a,
COL n
DOUT n DOUT n+1
D
OUT
n+2
D
OUT
n+3
INTERNAL
CLOCK
CLOCK SUSPEND
Clock suspend mode occurs when a column access/burst
is in progress and CKE is registered LOW. In the clock
suspend mode, the internal clock is deactivated, “freezing”
the synchronous logic.
For each positive clock edge on which CKE is sampled
LOW, the next internal positive clock edge is suspended.
Any command or data present on the input pins at the time
of a suspended internal clock edge is ignored; any data
present on the DQ pins remains driven; and burst counters
are not incremented, as long as the clock is suspended.
(See following examples.)
Clock suspend mode is exited by registering CKE HIGH; the
internal clock and related operation will resume on the
subsequent positive clock edge.
Clock Suspend During WRITE Burst
Clock Suspend During READ Burst
