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Fast clock speed: 100 and 83 MHz
Fast access times: 5.0/6.0 ns max.
Single clock operation
Single 3.3V 鈥?% and +5% power supply V
CC
Separate V
CCQ
for output buffer
Two chip enables for simple depth expansion
Address, data input, CE1, CE2, PTX, PTY, WEX, WEY,
and data output registers on-chip
Concurrent Reads and Writes
Two bidirectional data buses
Can be configured as separate I/O
Pass-through feature
Asynchronous output enables (OEX, OEY)
LVTTL-compatible I/O
Self-timed Write
Automatic power-down
176-pin TQFP package
The CY7C1299A allows the user to concurrently perform
Reads, Writes, or pass-through cycles in combination on the
two data ports. The two address ports (AX, AY) determine the
read or write locations for their respective data ports (DQX,
DQY).
All input pins except output enable pins (OEX, OEY) are gated
by registers controlled by a positive-edge-triggered clock input
(CLK). The synchronous inputs include all addresses, all data
inputs, depth-expansion chip enables (CE1, CE2),
pass-through controls (PTX and PTY), and read-write control
(WEX and WEY). The pass-through feature allows data to be
passed from one port to the other, in either direction. The PTX
input must be asserted to pass data from port X to port Y. The
PTY will likewise pass data from port Y to port X. A
pass-through operation takes precedence over a read
operation.
For the case when AX and AY are the same, certain protocols
are followed. If both ports are read, the reads occur normally.
If one port is written and the other is read, the read from the
array will occur before the data is written. If both ports are
written, only the data on DQY will be written to the array.
The CY7C1299A operates from a +3.3V power supply. All
inputs and outputs are LVTTL compatible. These dual I/O, dual
address synchronous SRAMs are well suited for ATM,
Ethernet switches, routers, cell/frame buffers, SNA switches
and shared memory applications.
The CY7C1299A needs one extra cycle after power for proper
power-on reset. The extra cycle is needed after V
CC
is stable
on the device. This device is available in a 176-pin TQFP
package.
Functional Description
The CY7C1299A SRAM integrates 32,768 脳 36 SRAM cells
with advanced synchronous peripheral circuitry. It employs
high-speed, low-power CMOS designs using advanced
triple-layer polysilicon, double-layer metal technology. Each
memory cell consists of four transistors and two high-valued
resistors.
Logic Block Diagram
[1]
C E1#
C E2
O E y#
Note:
1. For 32K x 36 devices, AX and AY are 15-bit-wide buses.
Cypress Semiconductor Corporation
Document #: 38-05138 Rev. *C
鈥?/div>
3901 North First Street
鈥?/div>
San Jose
,
CA 95134
鈥?/div>
408-943-2600
Revised May 14, 2003
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