128K x 36, 3.3V Synchronous IDT71V546S/XS
SRAM with ZBT™ Feature,
™
Burst Counter and Pipelined Outputs
Features
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128K x 36 memory configuration, pipelined outputs
Supports high performance system speed - 133 MHz
(4.2 ns Clock-to-Data Access)
ZBTTM Feature - No dead cycles between write and read
cycles
Internally synchronized registered outputs eliminate the
need to control OE
Single R/W (READ/WRITE) control pin
Positive clock-edge triggered address, data, and control
signal registers for fully pipelined applications
4-word burst capability (interleaved or linear)
Individual byte write (BW1 - BW4) control (May tie active)
Three chip enables for simple depth expansion
Single 3.3V power supply (±5%)
Packaged in a JEDEC standard 100-pin TQFP package
clock cycle, and two cycles later its associated data cycle occurs, be it
read or write.
The IDT71V546 contains data I/O, address and control signal registers. Output enable is the only asynchronous signal and can be used to
disable the outputs at any given time.
A Clock Enable (CEN) pin allows operation of the IDT71V546 to be
suspended as long as necessary. All synchronous inputs are ignored
when CEN is high and the internal device registers will hold their previous
values.
There are three chip enable pins (CE1, CE2, CE2) that allow the user
to deselect the device when desired. If any one of these three is not active
when ADV/LD is low, no new memory operation can be initiated and any
burst that was in progress is stopped. However, any pending data
transfers (reads or writes) will be completed. The data bus will tri-state two
cycles after the chip is deselected or a write initiated.
The IDT71V546 has an on-chip burst counter. In the burst mode, the
IDT71V546 can provide four cycles of data for a single address presented
to the SRAM. The order of the burst sequence is defined by the LBO input
pin. The LBO pin selects between linear and interleaved burst sequence.
The ADV/LD signal is used to load a new external address (ADV/LD =
LOW) or increment the internal burst counter (ADV/LD = HIGH).
The IDT71V546 SRAM utilizes IDT's high-performance, high-volume
3.3V CMOS process, and is packaged in a JEDEC standard 14mm x
20mm 100- pin thin plastic quad flatpack (TQFP) for high board density.
Description
The IDT71V546 is a 3.3V high-speed 4,718,592-bit (4.5 Megabit)
synchronous SRAM organized as 128K x 36 bits. It is designed to
eliminate dead bus cycles when turning the bus around between reads
and writes, or writes and reads. Thus it has been given the name ZBTTM,
or Zero Bus Turn-around.
Address and control signals are applied to the SRAM during one
Pin Description Summary
A0 - A16
Address Inputs
Input
Synchronous
Three Chip Enables
Input
Synchronous
OE
Output Enable
Input
Asynchronous
R/W
Read/Write Signal
Input
Synchronous
CEN
Clock Enable
Input
Synchronous
Individual Byte Write Selects
Input
Synchronous
Clock
Input
N/A
Advance Burst Address / Load New Address
Input
Synchronous
Linear / Interleaved Burst Order
Input
Static
I/O
Synchronous
CE1, CE2, CE2
BW1, BW2, BW3, BW4
CLK
ADV/LD
LBO
I/O0 - I/O31, I/OP1 - I/OP4
Data Input/Output
VDD
3.3V Power
Supply
Static
VSS
Ground
Supply
Static
3821 tbl 01
ZBT and Zero Bus Turnaround are trademarks of Integrated Device Technology, Inc. and the architecture is supported by Micron Technology and Motorola Inc.
OCTOBER 2008
1
©2007 Integrated Device Technology, Inc.
DSC-3821/05
IDT71V546, 128K x 36, 3.3V Synchronous SRAM with
ZBT™ Feature, Burst Counter and Pipelined Outputs
™
Commercial and Industrial Temperature Ranges
Functional Block Diagram
LBO
Address A [0:16]
128K x 36 BIT
MEMORY ARRAY
D
Q
Address
D
Q
Control
CE1, CE2, CE2
R/W
Input Register
CEN
ADV/LD
BWx
D
DI
DO
Control Logic
Q
Clk
Mux
Sel
D
Clk
Clock
Output Register
Q
Gate
OE
3821 drw 01
Data I/O [0:31], I/O P[1:4]
3
6.42
.
