GS816018/32/36BT-250/200/150
1M x 18, 512K x 32, 512K x 36
18Mb Sync Burst SRAMs
• FT pin for user-configurable flow through or pipeline
operation
• Single Cycle Deselect (SCD) operation
• 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 package
• RoHS-compliant 100-lead TQFP package available
Functional Description
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 risingedge-triggered Data Output Register.
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.
Ne
w
De
sig
Applications
The GS816018/32/36BT is an 18,874,368-bit (16,777,216-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.
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.
ct
Features
250 MHz–150 MHz
2.5 V or 3.3 V VDD
2.5 V or 3.3 V I/O
n—
Di
sco
nt
inu
ed
Pr
od
u
100-Pin TQFP
Commercial Temp
Industrial Temp
No
t
Re
co
m
me
nd
ed
for
Controls
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
Pipeline
3-1-1-1
Flow Through
2-1-1-1
Rev: 1.05 9/2008
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 GS816018/32/36BT 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
-200
-150
Unit
tKQ
tCycle
2.5
4.0
3.0
5.0
3.8
6.7
ns
ns
Curr (x18)
Curr (x32/x36)
295
345
245
285
200
225
mA
mA
tKQ
tCycle
5.5
5.5
6.5
6.5
7.5
7.5
ns
ns
Curr (x18)
Curr (x32/x36)
225
255
200
220
185
205
mA
mA
1/23
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2004, GSI Technology
