IS61LPD25632T/D/J
IS61LPD25636T/D/J
IS61LPD51218T/D/J
®
ISSI
256K x 32, 256K x 36, 512K x 18
SYNCHRONOUS PIPELINED,
APRIL 2003
DOUBLE-CYCLE DESELECT STATIC RAM
DESCRIPTION
FEATURES
The ISSI IS61LPD25632T/D/J,IS61LPD25636T/D/J,and
IS61LPD51218T/D/Jare high-speed, low-power synchro-
nous static RAMs designed to provide burstable, high-
performance memory for communication and networking
applications. The IS61LPD25632T/D/J is organized as
262,144 words by 32 bits and the IS61LPD25636T/D/J is
organizedas262,144wordsby36bits.TheIS61LPD51218T/
D/J is organized as 524,288 words by 18 bits. Fabricated
with ISSI's advanced CMOS technology, the device inte-
grates a 2-bit burst counter, high-speed SRAM core, and
high-drivecapabilityoutputsintoasinglemonolithiccircuit.
Allsynchronousinputspassthroughregisterscontrolledby
a positive-edge-triggered single clock input.
• Internal self-timed write cycle
• Individual Byte Write Control and Global Write
• Clock controlled, registered address, data and
control
• Linear burst sequence control using MODE
input
•
Three chip enable option for simple depth
expansion and address pipelining
• Common data inputs and data outputs
• JEDEC 100-Pin TQFP and
119-pin PBGA package
Writecyclesareinternallyself-timedandareinitiatedbythe
risingedgeoftheclockinput.Writecyclescanbeonetofour
bytes wide as controlled by the write control inputs.
• Power Supply
+3.3V VDD
Separate byte enables allow individual bytes to be written.
Bytewriteoperationisperformedbyusingbytewriteenable
(BWE). Input combined with one or more individual byte
write signals (BWx). In addition, Global Write (GW) is
available for writing all bytes at one time, regardless of the
byte write controls.
+3.3V or 2.5 VDDQ (I/O)
• Auto Power-down during deselect
• Double cycle deselect
• Snooze MODE for reduced-power standby
• JTAG Boundary Scan for PBGA package
• T Version (three chips selects)
• D Version (two chips selects)
• J Version (PBGA Package with JTAG)
Bursts can be initiated with either ADSP (Address Status
Processor) or ADSC (Address Status Cache Controller)
input pins. Subsequent burst addresses can be generated
internally and controlled by the ADV (burst address ad-
vance) input pin.
The mode pin is used to select the burst sequence order.
Linear burst is achieved when this pin is tied LOW. Inter-
leave burst is achieved when this pin is tied HIGH or left
floating.
FAST ACCESS TIME
Symbol
tKQ
Parameter
-250
2.6
4
-225
2.8
-200
3.1
5
-166
3.5
6
Units
ns
Clock Access Time
Cycle Time
tKC
4.4
ns
Frequency
250
225
200
166
MHz
Copyright © 2003 Integrated Silicon Solution, Inc. All rights reserved. ISSI reserves the right to make changes to this specification and its products at any time
without notice. ISSI assumes no liability arising out of the application or use of any information, products or services described herein. Customers are advised to
obtain the latest version of this device specification before relying on any published information and before placing orders for products.
Integrated Silicon Solution, Inc. — 1-800-379-4774
Rev. A
1
04/01/03