GS841Z18/36AT-180/166/150/100
100-Pin TQFP
Commercial Temp
Industrial Temp
Features
• 256K x 18 and 128K x 36 configurations
• User-configurable Pipelined and Flow Through mode
• NBT (No Bus Turn Around) functionality allows zero wait
• Fully pin-compatible with both pipelined and flow through
NtRAM™, NoBL™ and ZBT™ SRAMs
• IEEE 1149.1 JTAG-compatible Boundary Scan
• 3.3 V +10%/–5% core power supply
• 2.5 V or 3.3 V I/O supply
• LBO pin for Linear or Interleave Burst mode
• Byte write operation (9-bit Bytes)
• 3 chip enable signals for easy depth expansion
• Clock Control, registered, address, data, and control
• ZZ Pin for automatic power-down
• JEDEC-standard 100-lead TQFP package
• Pb-Free 100-lead TQFP package available
4Mb Pipelined and Flow Through
Synchronous NBT SRAMs
180 MHz–100 MHz
3.3 V V
DD
2.5 V and 3.3 V V
DDQ
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.
The GS841Z18/36AT may be configured by the user to
operate in Pipeline or Flow Through mode. Operating as a
pipelined synchronous device, in addition to the rising-edge-
triggered registers that capture input signals, the device
incorporates a rising-edge-triggered output register. For read
cycles, pipelined SRAM output data is temporarily stored by
the edge-triggered output register during the access cycle and
then released to the output drivers at the next rising edge of
clock.
The GS841Z18/36AT is implemented with GSI's high
performance CMOS technology and is available in a JEDEC-
Standard 100-pin TQFP package.
Functional Description
The GS841Z18/36AT is a 4Mbit Synchronous Static SRAM.
GSI's NBT SRAMs, like ZBT, NtRAM, NoBL or other
pipelined read/double late write or flow through read/single
late write SRAMs, allow utilization of all available bus
bandwidth by eliminating the need to insert deselect cycles
when the device is switched from read to write cycles.
Parameter Synopsis
Pipeline
3-1-1-1
Flow
Through
2-1-1-1
tCycle
t
KQ
I
DD
t
KQ
tCycle
I
DD
–180
5.5 ns
3.2 ns
335 mA
8 ns
9.1 ns
210 mA
–166
6.0 ns
3.5 ns
310 mA
8.5 ns
10 ns
190 mA
–150
6.6 ns
3.8 ns
280 mA
10 ns
12 ns
165 mA
–100
10 ns
4.5 ns
190 mA
12 ns
15 ns
135 mA
Rev: 1.02 11/2004
1/30
© 2001, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
GSI [ GSI TECHNOLOGY ]
