am49dl640bg Meet Spansion Inc., am49dl640bg Datasheet - Page 55

• Manufacturer Part Number: am49dl640bg
• Description: 64 Mbit 8 M ? 8-bit/4 M ? 16-bit Cmos And 32 Mbit 512k ? 16-bit Pseudo Static Ram Preliminary
• Manufacturer: Meet Spansion Inc.

pSRAM AC CHARACTERISTICS
Write Cycle
Notes:
1. If the device is using the I/Os to output data, input signals of reverse polarity must not be applied.
2. If OE# is high during the write cycle, the outputs will remain at high impedance.
3. If CE#1s, LB# or UB# goes low at the same time or after WE# goes low, the outputs will remain at high impedance.
4. If CE#1s, LB# or UB# goes high at the same time or before WE# goes high, the outputs will remain at high impedance.
54
Addresses
A0 to A20
I/O1 to 16
I/O1 to 16
LB#, UB#
Parameter
Symbol
CE#1
D
t
t
t
t
t
t
t
ODW
OEW
WE#
t
t
t
t
CE2
WC
WP
CW
BW
WR
AS
DS
DH
CH
OUT
D
IN
Description
Write Cycle Time
Write Pulse Time
Chip Enable to End of Write
Data Byte Control to End of Write
Address Setup Time
Write Recovery Time
WE# Low to Write to Output High-Z
WE# High to Write to Output Active
Data Set-up Time
Data Hold from Write Time
CE2 Hold Time
(Note 1)
t
CH
(Note 3)
t
Figure 30. Pseudo SRAM Write Cycle—WE# Control
AS
P R E L I M I N A R Y
t
ODW
Am49DL640BG
t
CW
t
BW
t
WC
t
WP
Max
Min
Min
Min
Min
Min
Min
Min
Min
Min
Min
High-Z
Valid Data In
t
DS
70
70
50
60
60
t
OEW
t
DH
t
WR
Speed
300
20
30
0
0
0
0
85
85
60
70
70
(Note 4)
March 8, 2002
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
µs