IS61VPS51218A
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, and
165-ball PBGA packages
• Lead-free available
DESCRIPTION
The ISSI IS61LPS/VPS25636A, IS61LPS25632A, IS64-
LPS25636A and IS61LPS/VPS51218A are high-speed,
low-power synchronous static RAMs designed to provide
burstable, high-performance memory for communication
and networking applications. The IS61LPS/VPS25636A
and IS64LPS25636A are organized as 262,144 words
by 36 bits. The IS61LPS25632A is organized as 262,144
words by 32 bits. The IS61LPS/VPS51218A is organized
as 524,288 words by 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
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.
