IS61LPS25672A
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
expansion 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: VDD 3.3V + 5%, VDDQ 3.3V/2.5V + 5%
VPS: VDD 2.5V + 5%, VDDQ 2.5V + 5%
• JEDEC 100-Pin TQFP, 119-ball PBGA, 165-ball
PBGA, and 209-ball (x72) packages
• Lead-free available
DESCRIPTION
The ISSI IS61LPS/VPS51236A, IS61LPS/VPS102418A,
and IS61LPS/VPS25672A are high-speed, low-power synchronous
static RAMs designed to provide burstable, highperformance
memory for communication and networking
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 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 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 generated
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.
