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CY7C1444AV25 Datasheet, PDF (1/26 Pages) Cypress Semiconductor – 36-Mbit (1M x 36/2M x 18) Pipelined DCD Sync SRAM
CY7C1444AV25
CY7C1445AV25
36-Mbit (1M x 36/2M x 18) Pipelined
DCD Sync SRAM
Features
Functional Description[1]
• Supports bus operation up to 250 MHz
• Available speed grades are 250, 200 and 167 MHz
• Registered inputs and outputs for pipelined operation
• Optimal for performance (Double-Cycle deselect)
• Depth expansion without wait state
• 2.5V core power supply
• 2.5V/1.8V I/O power supply
• Fast clock-to-output times
— 2.6 ns (for 250-MHz device)
• Provide high-performance 3-1-1-1 access rate
• User-selectable burst counter supporting Intel®
Pentium® interleaved or linear burst sequences
• Separate processor and controller address strobes
• Synchronous self-timed writes
• Asynchronous output enable
• CY7C1444AV25, CY7C1445AV25 available in
JEDEC-standard lead-free 100-pin TQFP package,
lead-free and non-lead-free 165-ball FBGA package
• IEEE 1149.1 JTAG-Compatible Boundary Scan
• “ZZ” Sleep Mode Option
The CY7C1444AV25/CY7C1445AV25 SRAM integrates 1M x
36/2M x 18 SRAM cells with advanced synchronous
peripheral circuitry and a two-bit counter for internal burst
operation. All synchronous inputs are gated by registers
controlled by a positive-edge-triggered Clock Input (CLK). The
synchronous inputs include all addresses, all data inputs,
address-pipelining Chip Enable (CE1), depth- expansion Chip
Enables (CE2 and CE3), Burst Control inputs (ADSC, ADSP,
and ADV), Write Enables (BWX, and BWE), and Global Write
(GW). Asynchronous inputs include the Output Enable (OE)
and the ZZ pin.
Addresses and chip enables are registered at rising edge of
clock when either Address Strobe Processor (ADSP) or
Address Strobe Controller (ADSC) are active. Subsequent
burst addresses can be internally generated as controlled by
the Advance pin (ADV).
Address, data inputs, and write controls are registered on-chip
to initiate a self-timed Write cycle.This part supports Byte Write
operations (see Pin Descriptions and Truth Table for further
details). Write cycles can be one to four bytes wide as
controlled by the byte write control inputs. GW active LOW
causes all bytes to be written. This device incorporates an
additional pipelined enable register which delays turning off
the output buffers an additional cycle when a deselect is
executed.This feature allows depth expansion without penal-
izing system performance.
The CY7C1444AV25/CY7C1445AV25 operates from a +2.5V
core power supply while all outputs operate with a +2.5V or
1.8V supply. All inputs and outputs are JEDEC-standard
JESD8-5-compatible.
Selection Guide
Maximum Access Time
Maximum Operating Current
Maximum CMOS Standby Current
250 MHz
200 MHz
167 MHz
Unit
2.6
3.2
3.4
ns
435
385
335
mA
120
120
120
mA
Note:
1. For best-practices recommendations, please refer to the Cypress application note System Design Guidelines on www.cypress.com.
Cypress Semiconductor Corporation • 198 Champion Court • San Jose, CA 95134-1709 • 408-943-2600
Document #: 38-05351 Rev. *E
Revised June 22, 2006