Table 21-5 Refresh Controller Bus Timing
Condition A: V
CC
= 2.7 V to 5.5 V, AV
CC
= 2.7 V to 5.5 V, V
REF
= 2.7 V to AV
CC
,
V
SS
= AV
SS
= 0 V, ø = 1 MHz to 8 MHz, T
a
= –20°C to +75°C (regular
specifications), T
a
= –40°C to +85°C (wide-range specifications)
Condition B: V
CC
= 3.15 V to 5.5 V, AV
CC
= 3.15 V to 5.5 V, V
REF
= 3.15 V to AV
CC
,
V
SS
= AV
SS
= 0 V, ø = 1 MHz to 13 MHz, T
a
= –20°C to +75°C (regular
specifications), T
a
= –40°C to +85°C (wide-range specifications)
Condition C: V
CC
= 5.0 V ± 10%, AV
CC
= 5.0 V ± 10%, V
REF
= 4.5 V to AV
CC
,
V
SS
= AV
SS
= 0 V, ø = 1 MHz to 18 MHz, T
a
= –20°C to +75°C (regular
specifications), T
a
= –40°C to +85°C (wide-range specifications)
Condition A Condition B
Condition C
8 MHz
13 MHz
16 MHz
18 MHz
Item
Symbol Min
Max
Min
Max
Min
Max
Min
Max
Unit
RAS
delay time 1
t
RAD1
—
60
—
50
—
30
—
30
ns
RAS
delay time 2
t
RAD2
—
60
—
50
—
30
—
30
RAS
delay time 3
t
RAD3
—
60
—
50
—
30
—
30
Row address hold time
*
t
RAH
25
—
20
—
15
—
15
—
RAS
precharge time
*
t
RP
85
—
55
—
45
—
40
—
CAS
to
RAS
precharge t
CRP
85
—
55
—
45
—
40
—
time
*
CAS
pulse width
t
CAS
100
—
55
—
40
—
35
—
RAS
access time
*
t
RAC
—
160
—
80
—
85
—
70
Address access time
t
AA
—
105
—
45
—
55
—
45
CAS
access time
*
t
CAC
—
50
—
30
—
30
—
25
Write data setup time 3
t
WDS3
50
—
20
—
15
—
10
—
CAS
setup time
*
t
CSR
20
—
10
—
15
—
10
—
Read strobe delay time
t
RSD
—
60
—
50
—
30
—
30
Note is on next page.
Test
Conditions
Figure 21-10
to
Figure 21-16
667
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