GS8640FZ18/36T-5.5/6.5/7.5/8
5.5 ns–8 ns
100-Pin TQFP
Commercial Temp
Industrial Temp
72Mb Flow Through
Synchronous NBT SRAM
2.5 V or 3.3 V V
DD
2.5 V or 3.3 V I/O
available bus bandwidth by eliminating the need to insert
deselect cycles when the device is switched from read to write
cycles.
Features
• NBT (No Bus Turn Around) functionality allows zero wait
read-write-read bus utilization; Fully pin-compatible with
Flow Through NtRAM™, NoBL™ and ZBT™ SRAMs
• 2.5 V or 3.3 V +10%/–10% core power supply
• 2.5 V or 3.3 V I/O supply
Because it is a synchronous device, address, data inputs, and
read/ write control inputs are captured on the rising edge of the
input clock. Burst order control (LBO) must be tied to a power
rail for proper operation. Asynchronous inputs include the
Sleep mode enable (ZZ) and Output Enable. Output Enable can
be used to override the synchronous control of the output
drivers and turn the RAM's output drivers off at any time.
Write cycles are internally self-timed and initiated by the rising
edge of the clock input. This feature eliminates complex off-
chip write pulse generation required by asynchronous SRAMs
and simplifies input signal timing.
• Flow Through mode
• LBO pin for Linear or Interleave Burst mode
• Pin compatible with 4Mb, 9Mb, 18Mb and 36Mb devices
• Byte write operation (9-bit Bytes)
• 3 chip enable signals for easy depth expansion
• ZZ Pin for automatic power-down
• JEDEC-standard 100-lead TQFP package
• RoHS-compliant 100-lead TQFP package available
The GS8640FZ18/36T is configured to operate in Flow
Through mode.
Functional Description
The GS8640FZ18/36T is a 72Mbit Synchronous Static SRAM.
GSI's NBT SRAMs, like ZBT, NtRAM, NoBL or other flow
through read/single late write SRAMs, allow utilization of all
The GS8640FZ18/36T is implemented with GSI's high
performance CMOS technology and is available in a JEDEC-
standard 100-pin TQFP package.
Parameter Synopsis
-5.5
-6.5
-7.5
-8
Unit
t
5.5
5.5
6.5
6.5
7.5
7.5
8.0
8.0
ns
ns
KQ
Flow
Through
2-1-1-1
tCycle
Curr (x18)
Curr (x36)
285
330
245
280
220
250
210
240
mA
mA
Packages listed with the additional “G” designator are 6/6 RoHS compliant.
Rev: 1.01 10/2013
1/21
© 2006, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.