
AC Electrical Characteristics
DSP56321 Technical Data, Rev. 11
Freescale Semiconductor
2-11
2.4.5
External Memory Expansion Port (Port A)
2.4.5.1 SRAM Timing
Table 2-8.
SRAM Timing
No.
Characteristics
Symbol
Expression
1
200 MHz
220 MHz
240 MHz
275 MHz
Unit
Min
Max
Min
Max
Min
Max
Min
Max
100 Address valid and AA
assertion pulse width
2
t
RC
, t
WC
(WS + 2)
×
T
C
4.0
[3
≤
WS
≤
7]
(WS + 3)
×
T
C
4.0
[WS
≥
8]
0.75
×
T
C
– 3.0
[WS = 3]
1.25
×
T
C
– 3.0
[WS
≥
4]
WS
×
T
C
4.0
[WS = 3]
(WS
0.5)
×
T
C
4.0
[WS
≥
4]
1.25
×
T
C
4.0
[3
≤
WS
≤
7]
2.25
×
T
C
4.0
[WS
≥
8]
(WS + 0.75)
×
T
C
5.8
[WS
≥
3]
(WS + 0.25)
×
T
C
6.5
[WS
≥
3]
21.0
51.0
—
18.8
46.0
—
16.9
41.9
—
15.0
36.0
—
ns
ns
101 Address and AA valid to
WR assertion
t
AS
0.75
3.25
—
—
0.41
2.69
—
—
0.13
2.21
—
—
–0.27
1.54
—
—
ns
ns
102 WR assertion pulse width
t
WP
11.0
13.5
—
—
9.65
11.93
—
—
8.51
10.6
—
—
6.9
8.72
—
—
ns
ns
103 WR deassertion to
address not valid
t
WR
2.25
7.25
—
—
1.69
6.24
—
—
1.21
5.38
—
—
0.54
4.18
—
—
ns
ns
104 Address and AA valid to
input data valid
t
AA
, t
AC
—
12.9
—
11.2
—
9.8
—
7.84
ns
105 RD assertion to input data
valid
t
OE
—
9.75
—
8.29
—
7.05
—
5.31
ns
106 RD deassertion to data
not valid (data hold time)
t
OHZ
0.0
—
0.0
—
0.0
—
0.0
—
ns
107 Address valid to WR
deassertion
2
t
AW
(WS + 0.75)
×
T
C
4.0
[WS
≥
3]
(WS
0.25)
×
T
C
5.4
[WS
≥
3]
14.75
—
13.06
—
11.64
—
9.63
—
ns
108 Data valid to WR
deassertion (data setup
time)
t
DS
(t
DW
)
8.35
—
7.11
—
6.07
—
4.6
—
ns
109 Data hold time from WR
deassertion
t
DH
1.25
×
T
C
4.0
[3
≤
WS
≤
7]
2.25
×
T
C
4.0
[WS
≥
8]
0.25
×
T
C
4.0
[WS
=
3]
–0.25
×
T
C
4.0
[WS
≥
4]
1.25
×
T
C
2.25
7.25
—
—
1.69
6.23
—
—
1.21
5.38
—
—
0.54
4.18
—
—
ns
ns
110 WR assertion to data
active
—
–2.75
–5.25
—
—
–2.86
–5.14
—
—
–2.96
–5.04
—
—
–3.1
–4.91
—
—
ns
ns
111 WR deassertion to data
high impedance
—
6.25
—
5.69
—
5.21
—
4.55
—
ns
112 Previous RD deassertion
to data active (write)
—
2.25
×
T
C
4.0
7.25
—
6.23
—
5.38
—
4.18
—
ns
113 RD deassertion time
—
1.75
×
T
C
3.0
[3
≤
WS
≤
7]
2.75
×
T
C
3.0
[WS
≥
8]
2.0
×
T
C
3.0
[3
≤
WS
≤
7]
3.0
×
T
C
3.0
[WS
≥
8]
5.75
10.75
—
—
4.96
9.51
—
—
4.3
8.47
—
—
3.36
7.0
—
—
ns
ns
114 WR deassertion time
4
—
7.0
12.0
—
—
6.1
10.6
—
—
5.3
9.5
—
—
4.27
7.91
—
—
ns
ns