GS81032AT Datasheet, PDF (1/23 Pages) GSI Technology – 32K x 32 1M Synchronous Burst SRAM

GS81032AT/Q-150/138/133/117/100/66
TQFP, QFP
Commercial Temp
Industrial Temp
32K x 32
1M Synchronous Burst SRAM
150 MHz–66 MHz
9 ns–18 ns
3.3 V V_DD
3.3 V and 2.5 V I/O
Features
• FT pin for user-configurable flow through or pipeline
operation
• Single Cycle Deselect (SCD) operation
• 3.3 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
• Default to Interleaved Pipeline mode
• Byte Write (BW) and/or Global Write (GW) operation
• Common data inputs and data outputs
• Clock Control, registered, address, data, and control
• Internal self-timed write cycle
• Automatic power-down for portable applications
• JEDEC-standard 100-lead TQFP or QFP package
-150 -138 -133 -117 -100 -66 Unit
Pipeline tCycle 6.6 7.25 7.5 8.5 10 12.5 ns
3-1-1-1 tKQ 3.8 4 4 4.5 5 6 ns
IDD 270 245 240 210 180 150 mA
Flow tCycle 10.5 15 15 15 15 20 ns
Through tKQ 9 9.7 10 11 12 18 ns
2-1-1-1 IDD 170 120 120 120 120 95 mA
Functional Description
Applications
The GS81032A is a 1,048,576-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
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.
SCD Pipelined Reads
The GS81032A is an 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.
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 GS81032A operates on a 3.3 V power supply and all
inputs/outputs are 3.3 V- and 2.5 V-compatible. Separate
output power (V_DDQ) pins are used to decouple output noise
from the internal circuit.
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.
Rev: 1.01 7/2001
1/23
© 2000, Giga Semiconductor, Inc.
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.