IS61SF25616 Datasheet, PDF (1/16 Pages) Integrated Silicon Solution, Inc – 256K x 16, 256K x 18 SYNCHRONOUS FLOW-THROUGH STATIC RAM

IS61SF25616
IS61SF25618
256K x 16, 256K x 18 SYNCHRONOUS
FLOW-THROUGH STATIC RAM
ISSI^®
APRIL 2001
FEATURES
• Fast access times: 8 ns, 8.5 ns, 10 ns, and 12 ns
• Internal self-timed write cycle
• Individual Byte Write Control and Global Write
• Clock controlled, registered address, data inputs
and control signals
• Pentium^TM or linear burst sequence control
using MODE input
• Three chip enables for simple depth expansion
and address pipelining
• Common data inputs and data outputs
• JEDEC 100-Pin TQFP and
119-pin PBGA package
• Single +3.3V +10%, –5% power supply
• Power-down snooze mode
DESCRIPTION
The ISSI IS61SF25616 and IS61SF25618 is a high-speed,
low-power synchronous static RAM designed to provide
a burstable, high-performance memory for high speed
networking and communication applications. It is organized
as 262,144 words by 16 bits and 18 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 monolithic 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 from
one to four bytes wide as controlled by the write control
inputs.
Separate byte enables allow individual bytes to be written.
BW1 controls DQ1-8, BW2 controls DQ9-16, conditioned
by BWE being LOW. A LOW on GW input would cause all
bytes to be written.
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 by the IS61SF25616 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.
FAST ACCESS TIME
Symbol
Parameter
8
8.5
10
12
Units
tKQ
Clock Access Time
8
8.5
10
12
ns
tKC
Cycle Time
10
11
15
15
ns
Frequency
100
90
66
66
MHz
ISSI reserves the right to make changes to its products at any time without notice in order to improve design and supply the best possible product. We assume no responsibility for any
errors which may appear in this publication. © Copyright 2001, Integrated Silicon Solution, Inc.
Integrated Silicon Solution, Inc. — 1-800-379-4774
1
Rev. A
04/17/01