dsp56004 Freescale Semiconductor, Inc, dsp56004 Datasheet - Page 40

• Manufacturer Part Number: dsp56004
• Description: Symphonytm Audio Dsp Family 24-bit Digital Signal Processors
• Manufacturer: Freescale Semiconductor, Inc

Note:
No.
Specifications
External Memory Interface (EMI) DRAM Refresh Timing
EXTERNAL MEMORY INTERFACE (EMI) DRAM REFRESH TIMING
2-16
83 Refresh Cycle Time
84 RAS Assertion Pulse
85 RAS Deassertation to
81 RAS Deassertation to
82 CAS Deassertation to
86 CAS Assertion to RAS
87 RAS Assertion to CAS
88 RAS Deassertation to
89 CAS Deassertation to
RAS Assertion
CAS Assertion
Width
RAS Assertion for
Refresh Cycle
Assertion on Refresh
Cycle
Deassertation on
Refresh Cycle
CAS Assertion on a
Refresh Cycle
Data Not Valid
1.
Characteristics
This happens when a Refresh Cycle is followed by an Access Cycle.
(C
L
Table 2-9 External Memory Interface (EMI) DRAM Refresh Timing
= 50 pF + 2 TTL Loads)
1
Sym.
Freescale Semiconductor, Inc.
t
t
t
t
t
t
CPN
t
CHR
t
t
RPC
RAS
CSR
OFF
RC
RP
RP
For More Information On This Product,
DSP56004/D, Rev. 3
Timing
Mode
slow
slow
slow
slow
slow
slow
slow
fast
fast
fast
fast
fast
fast
fast
Go to: www.freescale.com
6
4
5
3
6
4
5
3
5
3
6
4
12
8
T
Exp.
C
T
T
T
T
T
T
T
T
T
T
T
T
0
C
C
C
C
– 7
C
C
C
C
C
C
C
C
T
T
– 15
– 15
– 11
– 11
C
– 9
– 9
– 7
– 7
– 7
– 7
– 5
– 5
C
Min Max Min Max Min
113
240
160
111
105
50 MHz
73
93
53
71
95
55
13
65
89
49
0
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
181.8
121.2
81.9
51.6
75.9
45.6
66 MHz
84
54
71
38
70
40
65
34
8
0
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
148.2
67.1
42.4
54.7
98.8
65.1
40.4
55.7
59.1
34.4
50.7
5.3
30
32
26
MOTOROLA
81 MHz
0
Max
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns