GS8161E18(T/D)/GS816132(D)/GS816136(T/D)
250 MHz–133 MHz
100-Pin TQFP & 165-Bump BGA
Commercial Temp
Industrial Temp
1M x 18, 512K x 32, 512K x 36
18Mb Sync Burst SRAMs
2.5 V or 3.3 V V
DD
2.5 V or 3.3 V I/O
with the Linear Burst Order (LBO) input. The Burst function need not
be used. New addresses can be loaded on every cycle with no
degradation of chip performance.
Features
• FT pin for user-configurable flow through or pipeline
operation
• Dual Cycle Deselect (DCD) operation
• IEEE 1149.1 JTAG-compatible Boundary Scan
• 2.5 V or 3.3 V +10%/–10% core power supply
• 2.5 V or 3.3 V I/O supply
• LBO pin for Linear or Interleaved Burst mode
• Internal input resistors on mode pins allow floating mode pins
• Default to Interleaved Pipeline mode
• Byte Write (BW) and/or Global Write (GW) operation
• Internal self-timed write cycle
• Automatic power-down for portable applications
• JEDEC-standard 100-lead TQFP and 165-bump BGA
packages
Flow Through/Pipeline Reads
The function of the Data Output register can be controlled by the user
via the FT mode pin (Pin 14). Holding the FT mode pin low places the
RAM in Flow Through mode, causing output data to bypass the Data
Output Register. Holding FT high places the RAM in Pipeline mode,
activating the rising-edge-triggered Data Output Register.
DCD Pipelined Reads
The GS8161E18(T/D)/GS8161E32(D)/GS8161E36(T/D) is a DCD
(Dual Cycle Deselect) pipelined synchronous SRAM. SCD (Single
Cycle Deselect) versions are also available. DCD SRAMs pipeline
disable commands to the same degree as read commands. DCD
RAMs hold the deselect command for one full cycle and then begin
turning off their outputs just after the second rising edge of clock.
Functional Description
Byte Write and Global Write
Byte write operation is performed by using Byte Write enable (BW)
input combined with one or more individual byte write signals (Bx).
In addition, Global Write (GW) is available for writing all bytes at one
time, regardless of the Byte Write control inputs.
Applications
The GS8161E18(T/D)/GS8161E32(D)/GS8161E36(T/D) is a
18,874,368-bit high performance synchronous SRAM with a 2-bit
burst address counter. Although of a type originally developed for
Level 2 Cache applications supporting high performance CPUs, the
device now finds application in synchronous SRAM applications,
ranging from DSP main store to networking chip set support.
Sleep Mode
Low power (Sleep mode) is attained through the assertion (High) of
the ZZ signal, or by stopping the clock (CK). Memory data is retained
during Sleep mode.
Controls
Addresses, data I/Os, chip enable (E1), address burst control inputs
(ADSP, ADSC, ADV) and write control inputs (Bx, BW, GW) are
synchronous and are controlled by a positive-edge-triggered clock
input (CK). Output enable (G) and power down control (ZZ) are
asynchronous inputs. Burst cycles can be initiated with either ADSP
or ADSC inputs. In Burst mode, subsequent burst addresses are
generated internally and are controlled by ADV. The burst address
counter may be configured to count in either linear or interleave order
Core and Interface Voltages
The GS8161E18(T/D)/GS8161E32(D)/GS8161E36(T/D) operates on
a 2.5 V or 3.3 V power supply. All input are 3.3 V and 2.5 V
compatible. Separate output power (VDDQ) pins are used to decouple
output noise from the internal circuits and are 3.3 V and 2.5 V
compatible.
Parameter Synopsis
-250
-225
-200
-166 -150 -133 Unit
Pipeline
3-1-1-1
tKQ
2.5
4.0
2.7
4.4
3.0
5.0
3.4
6.0
3.8
6.7
4.0
7.5
ns
ns
tCycle
Curr (x18)
Curr (x36)
280
330
255
300
230
270
200
230
185
215
165
190
mA
mA
3.3 V
2.5 V
Curr (x18)
Curr (x36)
275
320
250
295
230
265
195
225
180
210
165
185
mA
mA
Flow Through
2-1-1-1
tKQ
5.5
5.5
6.0
6.0
6.5
6.5
7.0
7.0
7.5
7.5
8.5
8.5
ns
ns
tCycle
Curr (x18)
Curr (x36)
175
200
165
190
160
180
150
170
145
165
135
150
mA
mA
3.3 V
2.5 V
Curr (x18)
Curr (x36)
175
200
165
190
160
180
150
170
145
165
135
150
mA
mA
Rev: 2.14 3/2005
1/36
© 1999, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.