GS840E18AT-166 GSI TECHNOLOGY, GS840E18AT-166 Datasheet - Page 13

• Manufacturer Part Number: GS840E18AT-166
• Description: SRAM Chip Sync Dual 3.3V 4M-Bit 256K x 18 8.5ns/3.5ns 100-Pin TQFP Tray
• Manufacturer: GSI TECHNOLOGY

Specifications of GS840E18AT-166

• Package: 100TQFP
• Timing Type: Synchronous
• Density: 4 Mb
• Data Rate Architecture: SDR
• Typical Operating Supply Voltage: 3.3 V
• Number Of I/o Lines: 18 Bit
• Number Of Ports: 2
• Number Of Words: 256K

Synchronous Truth Table
Rev: 1.12 10/2004
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
Notes:
1.
2.
3.
4.
5.
6.
7.
Deselect Cycle, Power Down
Deselect Cycle, Power Down
Deselect Cycle, Power Down
Read Cycle, Continue Burst
Read Cycle, Continue Burst
Write Cycle, Continue Burst
Write Cycle, Continue Burst
Read Cycle, Suspend Burst
Read Cycle, Suspend Burst
Write Cycle, Suspend Burst
Write Cycle, Suspend Burst
Read Cycle, Begin Burst
Write Cycle, Begin Burst
Read Cycle, Begin Burst
X = Don’t Care, H = High, L = Low.
E = T (True) if E
W = T (True) and F (False) is defined in the Byte Write Truth Table preceding.
G is an asynchronous input. G can be driven high at any time to disable active output drivers. G low can only enable active drivers (shown
as “Q” in the Truth Table above).
All input combinations shown above are tested and supported. Input combinations shown in gray boxes need not be used to accomplish
basic synchronous or synchronous burst operations and may be avoided for simplicity.
Tying ADSP high and ADSC low allows simple non-burst synchronous operations. See BOLD items above.
Tying ADSP high and ADV low while using ADSC to load new addresses allows simple burst operations. See ITALIC items above.
Operation
2
= 1 and E
3
= 0; E = F (False) if E
Address
External
External
External
Current
Current
Current
Current
Used
None
None
None
Next
Next
Next
Next
Diagram
2
= 0 or E
State
Key
CW
CW
CR
CR
W
X
X
X
R
R
13/31
5
3
= 1.
E
H
H
H
H
H
L
L
L
X
X
X
X
L
L
1
GS840E18/32/36AT/B-190/180/166/150/100
E
X
F
F
T
T
T
X
X
X
X
X
X
X
X
2
ADSP ADSC
X
H
H
H
H
X
H
X
H
X
H
X
L
L
X
X
H
H
H
H
H
H
H
H
L
L
L
L
ADV
X
X
X
X
X
X
H
H
H
H
L
L
L
L
© 1999, GSI Technology
W
X
X
X
X
F
T
F
F
T
T
F
F
T
T
3
High-Z
High-Z
High-Z
DQ
Q
Q
D
Q
Q
D
D
Q
Q
D
D
4