GS8161E18BT-V Datasheet, PDF (1/35 Pages) GSI Technology – 1M x 18, 512K x 36, 512K x 36 18Mb Sync Burst SRAMs

Preliminary
GS8161ExxB(T/D)-xxxV
100-Pin TQFP & 165-Bump BGA
Commercial Temp
Industrial Temp
1M x 18, 512K x 36, 512K x 36
18Mb Sync Burst SRAMs
250 MHz–150 MHz
1.8 V or 2.5 V V_DD
1.8 V or 2.5 V I/O
Features
• FT pin for user-configurable flow through or pipeline
operation
• Dual Cycle Deselect (DCD) operation
• IEEE 1149.1 JTAG-compatible Boundary Scan
• 1.8 V or 2.5 V core power supply
• 1.8 V or 2.5 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 BGA packages
• RoHS-compliant 100-lead TQFP and 165 BGA packages
available
Functional Description
Applications
The GS8161ExxB(T/D)-xxxV 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.
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 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.
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 GS8161ExxB(T/D)-xxxV 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.
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.
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.
Core and Interface Voltages
The GS8161ExxB(T/D)-xxxV operates on a 1.8 V or 2.5 V power
supply. All inputs are 1.8 V or 2.5 V compatible. Separate output
power (V_DDQ) pins are used to decouple output noise from the
internal circuits and are 1..8 V or 2.5 V compatible.
Pipeline
3-1-1-1
Flow Through
2-1-1-1
Parameter Synopsis
-250 -200 -150 Unit
t_KQ
tCycle
3.0
3.0
3.8
ns
4.0
5.0
6.7
ns
Curr (x18)
Curr (x32/x36)
280
230
185
mA
330
270
210
mA
t_KQ
tCycle
5.5
6.5
7.5
ns
5.5
6.5
7.5
ns
Curr (x18)
Curr (x32/x36)
210
185
170
mA
240
205
190
mA
Rev: 1.01a 6/2006
1/35
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2004, GSI Technology