GS88018/32/36CT-xxxV
250 MHz–150 MHz
512K x 18, 256K x 32, 256K x 36
9Mb Sync Burst SRAMs
100-Pin TQFP
Commercial Temp
1.8 V or 2.5 V V
DD
1.8 V or 2.5 V I/O
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.
Features
• FT pin for user-configurable flow through or pipeline
operation
• Single Cycle Deselect (SCD) operation
• 1.8 V or 2.5 V core power supply
• 1.8 V or 2.5 V I/O supply
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.
• 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 package
• RoHS-compliant 100-lead TQFP package available
SCD Pipelined Reads
The GS88018/32/36CT-xxxV is a SCD (Single Cycle
Deselect) pipelined synchronous SRAM. DCD (Dual Cycle
Deselect) versions are also available. SCD SRAMs pipeline
deselect commands one stage less than read commands. SCD
RAMs begin turning off their outputs immediately after the
deselect command has been captured in the input registers.
Functional Description
Applications
The GS88018/32/36CT-xxxV is a 9,437,184-bit (8,388,608-bit
for x32 version) 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.
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.
Controls
Sleep Mode
Addresses, data I/Os, chip enables (E1, E2, E3), 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
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 GS88018/32/36CT-xxxV operates on a 1.8 V or 2.5 V
power supply. All input are 1.8 V or 2.5 V compatible.
Separate output power (V
) pins are used to decouple
DDQ
output noise from the internal circuits and are 1.8 V or 2.5 V
compatible.
Parameter Synopsis
-250
-200
-150
Unit
tKQ
3.0
4.0
3.0
5.0
3.8
6.7
ns
ns
tCycle
Pipeline
3-1-1-1
Curr (x18)
Curr (x32/x36)
175
200
150
165
125
145
mA
mA
tKQ
5.5
5.5
6.5
6.5
7.5
7.5
ns
ns
tCycle
Flow Through
2-1-1-1
Curr (x18)
Curr (x32/x36)
135
155
125
140
113
125
mA
mA
Rev: 1.04 6/2012
1/22
© 2011, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.