CY7C1297A Datasheet, PDF (1/13 Pages) Cypress Semiconductor – 64K X 18 Synchronous Burst SRAM

297A
CY7C1297A/
GVT7164B18
64K X 18 Synchronous Burst SRAM
Features
• Fast access times: 9 and 10 ns
• Fast clock speed: 66 and 50 MHz
• Provide high performance 2-1-1-1 access rate
• Fast OE access times: 5 and 6 ns
• Single +3.3V –5% and +10% power supply
• 5V tolerant inputs except I/Os
• Clamp diodes to V_SSQ at all inputs and outputs
• Common data inputs and data outputs
• Byte Write Enable and Global Write control
• Three chip enables for depth expansion and address
pipeline
• Address, data, and control registers
• Internally self-timed Write Cycle
• Burst control pins (interleaved or linear burst
sequence)
• Automatic power-down for portable applications
• High-density, high-speed packages
• Low-capacitive bus loading
• High 30-pF output drive capability at rated access time
Functional Description
The Cypress Synchronous Burst SRAM family employs
high-speed, low-power CMOS designs using advanced
double-layer polysilicon, double-layer metal technology. Each
memory cell consists of four transistors and two high-valued
resistors.
The CY7C1297A/GVT7164B18 SRAM integrates 65536 × 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 (CE), depth-expansion Chip
Enables (CE2 and CE2), Burst Control inputs (ADSC, ADSP,
and ADV), Write Enables (WEL, WEH, and BWE), and Global
Write (GW).
Asynchronous inputs include the Output Enable (OE), Burst
Mode Control (MODE), and Sleep Mode Control (ZZ). The
data outputs (DQ), enabled by OE, are also asynchronous.
Addresses and chip enables are registered with either
Address Status Processor (ADSP) or Address Status
Controller (ADSC) input pins. Subsequent burst addresses
can be internally generated as controlled by the Burst Advance
pin (ADV).
Address, data inputs, and Read controls are registered
on-chip to initiate self-timed Write cycle. Write cycles can be
one or two bytes wide as controlled by the Read control inputs.
Individual byte enables allow individual bytes to be written.
WEL controls DQ1–DQ8 and DQP1. WEH controls
DQ9–DQ16 and DQP2. WEL and WEH can be active only with
BWE being LOW. GW being LOW causes all bytes to be
written.
The CY7C1297A/GVT7164B18 operates from a +3.3V power
supply. All inputs and outputs are TTL-compatible. The device
is ideally suited for 486, Pentium®, 680 × 0, and PowerPC™
systems and for systems that benefit from a wide synchronous
data bus.
Selection Guide
Maximum Access Time
Maximum Operating Current
Maximum CMOS Standby Current
7C1297A-66
7164B18-9
9.0
240
2
7C1297A-50
7164B18-10
10.0
240
2
7C1297A1-50
7164B18-12
Unit
10.0
ns
240
mA
2
mA
Cypress Semiconductor Corporation • 3901 North First Street • San Jose • CA 95134 • 408-943-2600
Document #: 38-05204 Rev. *A
Revised January 19, 2003