
IDT70X525XML
Low Power 4K x 8 TriPort Static RAM
Functional Description
The IDT70X525X provides three ports with separate control, address,
and I/O pins that permit independent access for reads or writes to the two
banks of memory. These devices have an automatic power down feature
controlled by BE 0 and BE 1 on Port 1 and CE on Port 2 and Port 3. The
CE (or BE X ) controls on-chip power down circuitry that permits the
respective port to go into standby mode when not selected ( CE or BE X =
V IH ). When Port 1 is enabled, it has access to the full memory. When Port
2 is active it has access to Bank 1 of the memory. When Port 3 is active it
has access to Bank 2 of the memory. See Truth Table I for a description
of the Read/Write operation.
Truth Table I – Read/Write Control
Preliminary
Industrial Temperature Range
BE 0
H
L
L
BE 1
H
H
H
R/ W
X
L
H
CE
X
X
X
OE
X
X
L
D 0- D 15
Z
DATA IN
DATA OUT
Function
Port Deselected
Data on port written into Memory Bank 0
Data in Memory Bank 0 output on port
PORT 1
H
H
X
L
X
L
L
X
L
X
L
H
X
X
X
X
X
X
X
H
X
L
H
X
X
DATA IN
DATA OUT
Z
X
Z
Data on port written into Memory Bank 1
Data in Memory Bank 1 output on port
Outputs Disabled
Not Allowed
Port Deselected
PORT 2
or
PORT 3
X
X
X
H
X
X
X
H
L
H
X
X
L
L
X
H
X
L
H
X
DATA IN
DATA OUT
Z
Z
Data on port written into Memory Bank (2)
Data in Memory Bank (2) output on port
Outputs Disabled
BE 0 = BE 1 = CE P 3 = V IH , Sleep mode
5681 tbl 13
NOTE:
1. Both BE 0 , and BE 1 cannot be active ( BE x = V IL ) simultaneously.
2. Memory Bank 0 for Port 2. Memory Bank 1 for Port 3.
12
6.42