Feature - No dead cycles between write and read cycles
u
Internally synchronized output buffer enable eliminates the
u
Single R/W (READ/WRITE) control pin
u
Positive clock-edge triggered address, data, and control
signal registers for fully pipelined applications
u
4-word burst capability (interleaved or linear)
u
Individual byte write (BW
1
-
BW
4
) control (May tie active)
u
Three chip enables for simple depth expansion
u
3.3V power supply (±5%)
u
2.5V I/O Supply (V
DDQ
)
u
Power down controlled by ZZ input
u
Packaged in a JEDEC standard 100-pin plastic thin quad
need to control
OE
(3.2 ns Clock-to-Data Access)
Preliminary
IDT71V65612
IDT71V65812
flatpack (TQFP), 119 ball grid array (BGA) and 165 fine pitch
ball grid array (fBGA)
The IDT71V65612/5812 are 3.3V high-speed 9,437,184-bit
(9 Megabit) synchronous SRAMS. They are designed to eliminate dead
bus cycles when turning the bus around between reads and writes, or
writes and reads. Thus, they have been given the name ZBT
TM
, or Zero
Bus Turnaround.
Description
Address and control signals are applied to the SRAM during one clock
cycle, and two cycles later the associated data cycle occurs, be it read
or write. The IDT71V65612/5812 contain 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 IDT71V65612/5812
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 (CE
1
, CE
2
,
CE
2
) that allow the
user to deselect the device when desired. If any one of these three are
not asserted when ADV/LD is low, no new memory operation can be
initiated. However, any pending data transfers (reads or writes) will be
completed. The data bus will tri-state two cycles after chip is deselected or
a write is initiated.
The IDT71V65612/5812 has an on-chip burst counter. In the burst
mode, the IDT71V65612/5812 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 IDT71V65612/5812 SRAM utilize IDT's latest high-performance
CMOS process, and are packaged in a JEDEC Standard 14mm x 20mm
100-pin thin plastic quad flatpack (TQFP) as well as a 119 ball grid array
(BGA) and 165 fine pitch ball grid array (fBGA).
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Output
Input
I/O
Supply
Supply
Synchronous
Synchronous
Asynchronous
Synchronous
Synchronous
Synchronous
N/A
Synchronous
Static
N/A
N/A
N/A
N/A
Asynchronous
Synchronous
Static
Static
5314 tbl 01
Pin Description Summary
A
0
-A
18
CE
1
, CE
2
,
CE
2
OE
R/W
CEN
BW
1
,
BW
2
,
BW
3
,
BW
4
CLK
ADV/LD
LBO
TMS
TDI
TCK
TDO
ZZ
I/O
0
-I/O
31
, I/O
P1
-I/O
P4
V
DD
, V
DDQ
V
SS
Address Inputs
Chip Enables
Output Enable
Read/Write Signal
Clock Enable
Individual Byte Write Selects
Clock
Advance burst address / Load new address
Linear / Interleaved Burst Order
Test Mode Select
Test Data Input
Test Clock
Test Data Output
Sleep Mode
Data Input / Output
Core Power, I/O Power
Ground
ZBT and Zero Bus Turnaround are trademarks of Integrated Device Technology, Inc. and the architecture is supported by Micron Technology and Motorola, Inc.
