Preliminary
GS8160F18/32/36T-7/8/8.5/10/11
7 ns–11 ns
100-Pin TQFP
Commercial Temp
Industrial Temp
1M x 18, 512K x 32, 512K x 36
16Mb Sync Burst SRAMs
2.5 V V
DD
2.5 V or 3.3 V I/O
should be designed with VSS connected to the FT pin location
Features
to ensure the broadest access to multiple vendor sources.
Boards designed with FT pin pads tied low may be stuffed with
GSI’s pipeline/flow through-configurable Burst RAMs or any
vendor’s flow through or configurable Burst SRAM. Boards
designed with the FT pin location tied high or floating must
employ a non-configurable flow through Burst RAM, like this
RAM, to achieve flow through functionality.
• Flow Through mode operation; Pin 14 = No Connect
• 2.5 V +10%/–5% 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
• 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
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.
-7 -7.5 -8 -8.5 -10 -11 Unit
Flow
tKQ
tCycle
7.0 7.5
8
8.5 10 11 ns
Through
2-1-1-1
8.5 10 10 10 10 15 ns
205 185 185 185 185 140 mA
240 210 210 210 210 160 mA
240 210 210 210 210 160 mA
Sleep Mode
Curr (x18)
Curr (x32)
Curr (x36)
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
Functional Description
The GS8160F18/32/36T operates on a 2.5 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
Applications
The GS8160F18/32/36T is a 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.
internal circuits and are 3.3 V- and 2.5 V-compatible.
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
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.
Designing For Compatibility
The JEDEC standard for Burst RAMS calls for a FT mode pin
option on Pin 14. Board sites for flow through Burst RAMS
Rev: 2.06 11/2000
1/23
© 1999, Giga Semiconductor, Inc.
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.