IS61vPS25672A IS61lPS25672A
IS61vPS51236A IS61lPS51236A
IS61vPS102418A IS61lPS102418A
256K x 72, 512K x 36, 1024K x 18
18Mb SYNCHRONOUS PIPElINED,
SINglE CYClE DESElECT STATIC RAM
FEATURES
• Internal self-timed write cycle
• Individual Byte Write Control and Global Write
• Clock controlled, registered address, data and
control
• Burst sequence control using MODE input
• Three chip enable option for simple depth ex-
pansion and address pipelining
• Common data inputs and data outputs
• Auto Power-down during deselect
• Single cycle deselect
• Snooze MODE for reduced-power standby
• JTAG Boundary Scan for PBGA package
• Power Supply
LPS: V
dd
3.3V + 5%,
V
ddq
3.3V/2.5V + 5%
VPS: V
dd
2.5V + 5%,
V
ddq
2.5V + 5%
• JEDEC 100-Pin TQFP, 119-ball PBGA, 165-ball
PBGA, and 209-ball (x72) packages
• Lead-free available
JUlY 2014
and IS61LPS/VPS25672A are high-speed, low-power
synchronous static
RAMs
designed to provide burstable,
high-performance
memory for communication and network-
ing applications. The IS61LPS/VPS51236A
is organized
as 524,288 words by 36 bits, the IS61LPS/VPS102418A
is
organized as 1,048,576 words by 18 bits, and the IS61LPS/
VPS25672A is organized as 262,144 words by 72 bits.
Fabricated with
ISSI
's advanced CMOS technology, the
device integrates a 2-bit burst counter, high-speed SRAM
core, and high-drive capability outputs into a single mono-
lithic circuit. All synchronous inputs pass through registers
controlled by a positive-edge-triggered single clock input.
Write cycles are internally self-timed and are initiated by
the rising edge of the clock input. Write cycles can be one
to four bytes wide as controlled by the write control inputs.
Separate byte enables allow individual bytes to be written.
The byte write operation is performed by using the byte write
enable (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.
Bursts can be initiated with either ADSP (Address Status
Processor) or
ADSC (Address Status Cache Controller)
input pins. Subsequent burst addresses can be gener-
ated internally and controlled by the
ADV (burst address
advance) input pin.
The mode pin is used to select the burst sequence order,
Linear burst is achieved when this pin is tied LOW. Interleave
burst is achieved when this pin is tied HIGH or left floating.
DESCRIPTION
The
ISSI
IS61LPS/VPS51236A, IS61LPS/VPS102418A,
FAST ACCESS TIME
Symbol
t
kq
t
kc
Parameter
Clock Access Time
Cycle Time
Frequency
250
2.6
4
250
200
3.1
5
200
Units
ns
ns
MHz
Copyright © 2014 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. does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause
failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless Integrated Silicon Solution, Inc. receives written
assurance to its satisfaction, that:
a.) the risk of injury or damage has been minimized;
b.) the user assume all such risks; and
c.) potential liability of Integrated Silicon Solution, Inc is adequately protected under the circumstances
Integrated Silicon Solution, Inc. — 1-800-379-4774
Rev. O
07/07/2014
1