HY[B/E]18L256160B[C/F]X-7.5
256-Mbit Mobile-RAM
Functional Description
2.4.8.2
CONCURRENT AUTO PRECHARGE
A READ or WRITE burst with Auto Precharge enabled can be interrupted by a subsequent READ or WRITE
command issued to a different bank.
Figure 37 shows a READ with Auto Precharge to bank n, interrupted by a READ (with or without Auto Precharge)
to bank m. The READ to bank m will interrupt the READ to bank n, CAS latency later. The precharge to bank n
will begin when the READ to bank m is registered.
Figure 38 shows a READ with Auto Precharge to bank n, interrupted by a WRITE (with or without Auto Precharge)
to bank m. The precharge to bank n will begin when the WRITE to bank m is registered. DQM should be pulled
HIGH two clock cycles prior to the WRITE to prevent bus contention.
Figure 39 shows a WRITE with Auto Precharge to bank n, interrupted by a READ (with or without Auto Precharge)
to bank m. The precharge to bank n will begin tWR after the new command to bank m is registered. The last valid
data-in to bank n is one clock cycle prior to the READ to bank m.
Figure 40 shows a WRITE with Auto Precharge to bank n, interrupted by a WRITE (with or without Auto
Precharge) to bank m. The precharge to bank n will begin tWR after the WRITE to bank m is registered. The last
valid data-in to bank n is one clock cycle prior to the WRITE to bank m.
#,+
./0
2$ꢎ!0
./0
2%!$
./0
./0
./0
./0
#OMMAN
RESS
"ANK N
#OL B
"ANK M
#OL X
!
#,ꢒꢁ
T20 ꢌBANK Nꢍ
$/ Bꢔꢀ
$/ B
$/ X
$/ Xꢔꢀ
$/ Xꢔꢁ
$1
ꢒ $ONgT #ARE
2$ꢎ!0 ꢒ 2EA WITH !UTO 0RECHARGEꢕ 2%!$ ꢒ 2EA WITH OR WITHOUT !UTO 0RECHARGE
#, ꢒ ꢁ AN "URST ,ENGTH ꢒ ꢈ IN THE CASE SHOWN
2EA WITH !UTO 0RECHARGE TO BANK N IS INTERRUPTE BY SUBSEQUENT 2EA TO BANK M
Figure 37 READ with Auto Precharge Interrupted by READ
#,+
./0
2$ꢎ!0
./0
./0
72)4%
./0
./0
./0
#OMMAN
RESS
"ANK N
#OL B
"ANK M
#OL X
!
$1-
#,ꢒꢁ
T20 ꢌBANK Nꢍ
$) Xꢔꢀ
$/ B
$) X
$) Xꢔꢁ
$) Xꢔꢆ
$1
ꢒ $ONgT #ARE
2$ꢎ!0 ꢒ 2EA WITH !UTO 0RECHARGEꢕ 72)4% ꢒ 7RITE WITH OR WITHOUT !UTO 0RECHARGE
#, ꢒ ꢁ AN "URST ,ENGTH ꢒ ꢈ IN THE CASE SHOWN
2EA WITH !UTO 0RECHARGE TO BANK N IS INTERRUPTE BY SUBSEQUENT 7RITE TO BANK M
Figure 38 READ with Auto Precharge Interrupted by WRITE
Data Sheet
32
Rev. 1.11, 2007-01
07142005-CR47-RB2E