
DSP56303 Technical Data, Rev. 11
2-20
Freescale Semiconductor
Specifications
172
RAS assertion to row address not valid
tRAH
1.75
× TC 4.0
13.5
—
ns
173
Column address valid to CAS assertion
tASC
0.75
× T
C 4.0
3.5
—
ns
174
CAS assertion to column address not valid
tCAH
5.25
× TC 4.0
48.5
—
ns
175
RAS assertion to column address not valid
tAR
7.75
× TC 4.0
73.5
—
ns
176
Column address valid to RAS deassertion
tRAL
6
× T
C 4.0
56.0
—
ns
177
WR deassertion to CAS assertion
tRCS
3.0
× TC 4.0
26.0
—
ns
178
CAS deassertion to WR
4 assertion
tRCH
1.75
× TC – 3.7
13.8
—
ns
179
RAS deassertion to WR4 assertion
tRRH
0.25
× T
C 2.0
0.5
—
ns
180
CAS assertion to WR deassertion
tWCH
5
× TC 4.2
45.8
—
ns
181
RAS assertion to WR deassertion
tWCR
7.5
× TC 4.2
70.8
—
ns
182
WR assertion pulse width
tWP
11.5
× T
C 4.5
110.5
—
ns
183
WR assertion to RAS deassertion
tRWL
11.75
× TC 4.3
113.2
—
ns
184
WR assertion to CAS deassertion
tCWL
10.25
× TC 4.3
98.2
—
ns
185
Data valid to CAS assertion (write)
tDS
5.75
× T
C 4.0
53.5
—
ns
186
CAS assertion to data not valid (write)
tDH
5.25
× TC 4.0
48.5
—
ns
187
RAS assertion to data not valid (write)
tDHR
7.75
× TC 4.0
73.5
—
ns
188
WR assertion to CAS assertion
tWCS
6.5
× T
C 4.3
60.7
—
ns
189
CAS assertion to RAS assertion (refresh)
tCSR
1.5
× TC 4.0
11.0
—
ns
190
RAS deassertion to CAS assertion (refresh)
tRPC
2.75
× TC 4.0
23.5
—
ns
191
RD assertion to RAS deassertion
tROH
11.5
× T
C 4.0
111.0
—
ns
192
RD assertion to data valid
tGA
10
× TC 7.0
—
93.0
ns
193
RD deassertion to data not valid
5
tGZ
0.0
—
ns
194
WR assertion to data active
0.75
× T
C – 1.5
6.0
—
ns
195
WR deassertion to data high impedance
0.25
× TC
—2.5
ns
Notes:
1.
The number of wait states for an out-of-page access is specified in the DRAM Control Register.
2.
The refresh period is specified in the DRAM Control Register.
3.
Use the expression to compute the maximum or minimum value listed (or both if the expression includes
±) .
4.
Either tRCH or tRRH must be satisfied for read cycles.
5.
RD deassertion always occurs after CAS deassertion; therefore, the restricted timing is tOFF and not tGZ.
Table 2-11.
DRAM Out-of-Page and Refresh Timings, Eleven Wait States1,2 (Continued)
No.
Characteristics
Symbol
Expression3
100 MHz
Unit
Min
Max