
ELECTRICAL DATA
S3C2440A RISC MICROPROCESSOR
27-36
Table 27-8. ROM/SRAM Bus Timing Constants
(V
DDi,
V
DDalive,
V
DDiarm
= 1.2 V
±
0.1 V, T
A
= –40 to 85
°
C, V
DDMOP
= 3.3V
±
0.3V / 3.0V
±
0.3V / 2.5V
±
0.2V / 1.8V
±
0.1V)
Parameter
Symbol
Min
(V
DDMOP
=
3.3V/3.0V/2.5V/1.8V)
Typ
Max
(V
DDMOP
=
3.3V/3.0V/2.5V/1.8V)
Unit
ROM/SRAM address delay
t
RAD
2 / 2 / 2 / 3
–
6 / 6 / 7 / 8
ns
ROM/SRAM chip select delay
t
RCD
2 / 2 / 3 / 3
–
6 / 6 / 6 / 7
ns
ROM/SRAM output enable delay
t
ROD
2 / 2 / 2 / 3
–
5 / 5 / 5 / 6
ns
ROM/SRAM read data setup time.
t
RDS
1 / 1 / 1 / 2
–
– / – / – / –
ns
ROM/SRAM read data hold time.
t
RDH
0 / 0 / 0 / 0
–
– / – / – / –
ns
ROM/SRAM byte enable delay
t
RBED
2 / 2 / 2 / 3
–
5 / 5 / 5 / 7
ns
ROM/SRAM write byte enable delay
t
RWBED
2 / 2 / 2 / 3
–
5 / 5 / 6 / 7
ns
ROM/SRAM output data delay
t
RDD
2 / 2 / 2 / 2
–
6 / 6 / 6 / 7
ns
ROM/SRAM external wait setup time
t
WS
3 / 3 / 4 / 4
–
– / – / – / –
ns
ROM/SRAM external wait hold time
t
WH
0 / 0 / 0 / 0
–
– / – / – / –
ns
ROM/SRAM write enable delay
t
RWD
2 / 2 / 2 / 3
–
5 / 5 / 6 / 7
ns
Table 27-9. Memory Interface Timing Constants
(V
DDi,
V
DDalive,
V
DDiarm
= 1.2 V
±
0.1 V, T
A
= –40 to 85
°
C, V
DDMOP
= 3.3V
±
0.3V / 3.0V
±
0.3V / 2.5V
±
0.2V / 1.8V
±
0.1V)
Parameter
Symbol
Min
Typ
Max
Unit
SDRAM address delay
t
SAD
1
–
4
ns
SDRAM chip select delay
t
SCSD
1
–
3
ns
SDRAM row active delay
t
SRD
1
–
3
ns
SDRAM column active delay
t
SCD
1
–
3
ns
SDRAM byte enable delay
t
SBED
1
–
3
ns
SDRAM write enable delay
t
SWD
1
–
2
ns
SDRAM read data setup time
t
SDS
2 / 3 / 3 / 5 *
–
–
ns
SDRAM read data hold time
t
SDH
0
–
–
ns
SDRAM output data delay
t
SDD
1
–
4
ns
SDRAM clock enable delay
T
cked
2
–
3
ns
NOTE:
Minimum t
SDS
= 2ns / 3ns / 3ns, when V
DDMOP
= 3.3V / 3.0V / 2.5V / 1.8V respectively.