HIGH SPEED
2K X 8 DUAL-PORT
STATIC RAM
WITH INTERRUPTS
Features
◆
IDT71321SA/LA
IDT71421SA/LA
◆
◆
High-speed access
– Commercial: 20/25/35/55ns (max.)
– Industrial: 25/55ns (max.)
Low-power operation
– IDT71321/IDT71421SA
—
Active: 325mW (typ.)
—
Standby: 5mW (typ.)
– IDT71321/421LA
—
Active: 325mW (typ.)
—
Standby: 1mW (typ.)
Two
INT
flags for port-to-port communications
◆
◆
◆
◆
◆
◆
◆
◆
◆
MASTER IDT71321 easily expands data bus width to 16-or-
more-bits using SLAVE IDT71421
On-chip port arbitration logic (IDT71321 only)
BUSY
output flag on IDT71321;
BUSY
input on IDT71421
Fully asynchronous operation from either port
Battery backup operation – 2V data retention (LA only)
TTL-compatible, single 5V ±10% power supply
Available in 52-Pin PLCC, 64-Pin TQFP, and 64-Pin STQFP
Industrial temperature range (–40°C to +85°C) is available
for selected speeds
Green parts available, see ordering information
Functional Block Diagram
OE
L
CE
L
R/W
L
OE
R
CE
R
R/W
R
I/O
0L
- I/O
7L
I/O
Control
BUSY
L
A
10L
A
0L
(1,2)
I/O
Control
I/O
0R
-I/O
7R
BUSY
R
Address
Decoder
11
(1,2)
MEMORY
ARRAY
11
Address
Decoder
A
10R
A
0R
CE
L
OE
L
R/W
L
ARBITRATION
and
INTERRUPT
LOGIC
CE
R
OE
R
R/W
R
INT
L
(2)
INT
R
2691 drw 01
(2)
NOTES:
1. IDT71321 (MASTER):
BUSY
is open drain output and requires pullup resistor of 270Ω.
IDT71421 (SLAVE):
BUSY
is input.
2. Open drain output: requires pullup resistor of 270Ω.
OCTOBER 2008
1
©2008 Integrated Device Technology, Inc.
DSC-2691/13
IDT71321SA/LA and IDT71421SA/LA
High Speed 2K x 8 Dual-Port Static RAM with Interrupts
Industrial and Commercial Temperature Ranges
Description
The IDT71321/IDT71421 are high-speed 2K x 8 Dual-Port Static
RAMs with internal interrupt logic for interprocessor communications.
The IDT71321 is designed to be used as a stand-alone 8-bit Dual-
Port Static RAM or as a "MASTER" Dual-Port Static RAM together
with the IDT71421 "SLAVE" Dual-Port in 16-bit-or-more word width
systems. Using the IDT MASTER/SLAVE Dual-Port Static RAM ap-
proach in 16-or-more-bit memory system applications results in full
speed, error-free operation without the need for additional discrete
logic.
Both devices provide two independent ports with separate control,
address, and I/O pins that permit independent, asynchronous access
for reads or writes to any location in memory. An automatic power
down feature, controlled by
CE,
permits the on chip circuitry of each
port to enter a very low standby power mode.
Fabricated using IDT's CMOS high-performance technology, these
devices typically operate on only 325mW of power. Low-power (LA)
versions offer battery backup data retention capability, with each Dual-
Port typically consuming 200µW from a 2V battery.
The IDT71321/IDT71421 devices are packaged in 52-pin PLCCs,
64-pin TQFPs, and 64-pin STQFPs.
INDEX
A
1L
A
2L
A
3L
A
4L
A
5L
A
6L
A
7L
A
8L
A
9L
I/O
0L
I/O
1L
I/O
2L
I/O
3L
87 6 5 4 3 2 1 52 51 50 49 48 47
46
9
45
10
44
11
43
12
42
IDT71321/421J
13
41
(4)
J52-1
14
40
15
39
PLCC
38
16
Top View
(5)
37
17
36
18
35
19
20
34
21 22 23 24 25 26 27 28 29 30 31 32 33
I/O
4L
I/O
5L
I/O
6L
I/O
7L
NC
GND
I/O
0R
I/O
1R
I/O
2R
I/O
3R
I/O
4R
I/O
5R
I/O
6R
R/W
L
CE
L
V
CC
CE
R
R/W
R
BUSY
R
INT
R
A
10R
Pin Configurations
(1,2,3)
INT
L
BUSY
L
A
0L
OE
L
A
10L
OE
R
A
0R
A
1R
A
2R
A
3R
A
4R
A
5R
A
6R
A
7R
A
8R
A
9R
NC
I/O
7R
2691 drw 02
INDEX
OE
L
A
0L
A
1L
A
2L
A
3L
A
4L
A
5L
A
6L
N/C
A
7L
A
8L
A
9L
N/C
I/O
0L
I/O
1L
I/O
2L
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
N/C
N/C
A
10L
INT
L
BUSY
L
R/W
L
CE
L
V
CC
V
CC
CE
R
R/W
R
BUSY
R
INT
R
A
10R
N/C
N/C
,
2
6.42
I/O
3L
N/C
I/O
4L
I/O
5L
I/O
6L
I/O
7L
N/C
GND
GND
I/O
0R
I/O
1R
I/O
2R
I/O
3R
N/C
I/O
4R
I/O
5R
NOTES:
1. All V
CC
pins must be connected to power supply.
2. All GND pins must be connected to ground supply.
3. J52-1 package body is approximately .75 in x .75 in x .17 in.
PN64-1 package body is approximately 14mm x 14mm x 1.4mm.
PP64-1 package body is approximately 10mm x 10mm x 1.4mm.
4. This package code is used to reference the package diagram.
5. This text does not indicate orientation of the actual part-marking.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
IDT71321/421PF or TF
PN64-1 / PP64-1
(4)
64-Pin TQFP
64-Pin STQFP
Top View
(5)
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
OE
R
A
0R
A
1R
A
2R
A
3R
A
4R
A
5R
A
6R
N/C
A
7R
A
8R
A
9R
N/C
N/C
I/O
7R
I/O
6R
,
2691 drw 03
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
IDT71321SA/LA and IDT71421SA/LA
High Speed 2K x 8 Dual-Port Static RAM with Interrupts
Industrial and Commercial Temperature Ranges
Capacitance
(1)
Symbol
C
IN
C
OUT
(TA = +25°C, f = 1.0MHz) TQFP Only
Parameter
Input Capacitance
Output Capacitance
Conditions
(2)
V
IN
= 3dV
V
OUT
= 3dV
Max.
9
10
Unit
pF
pF
2691 tbl 00
Recommended Operating
Temperature and Supply Voltage
(1,2)
Grade
Commercial
Industrial
Ambient
Temperature
0
O
C to +70
O
C
-40
O
C to +85
O
C
GND
0V
0V
Vcc
5.0V
+
10%
5.0V
+
10%
2691 tbl 02
NOTES:
1. This parameter is determined by device characterization but is not production
tested.
2. 3dv references the interpolated capacitance when the input and output signals
switch from 0V to 3V or from 3V to 0V.
NOTES:
1. This is the parameter T
A
. This is the "instant on" case temperature.
2. Industrial temperature: for specific speeds, packages and powers contact your
sales office.
Absolute Maximum Ratings
(1)
Symbol
V
TERM
(2)
Rating
Terminal Voltage
with Respect
to GND
Temperature
Under Bias
Storage
Temperature
DC Output
Current
Commercial
& Industrial
-0.5 to +7.0
Unit
V
Recommended DC Operating
Conditions
Symbol
V
CC
GND
Parameter
Supply Voltage
Ground
Input High Voltage
Input Low Voltage
Min.
4.5
0
2.2
-0.5
(1)
Typ.
5.0
0
____
Max.
5.5
0
6.0
(2)
0.8
Unit
V
V
V
V
2691 tbl 03
T
BIAS
T
STG
I
OUT
-55 to +125
-65 to +150
50
o
C
C
V
IH
V
IL
____
o
mA
2691 tbl 01
NOTES:
1. V
IL
(min.) = -1.5V for pulse width less than 10ns.
2. V
TERM
must not exceed Vcc + 10%.
NOTES:
1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS
may cause permanent damage to the device. This is a stress rating only
and functional operation of the device at these or any other conditions
above those indicated in the operational sections of the specification is not
implied. Exposure to absolute maximum rating conditions for extended
periods may affect reliability.
2. V
TERM
must not exceed V
CC
+ 10% for more than 25% of the cycle time or 10ns
maximum, and is limited to < 20mA for the period of V
TERM
> V
CC
+ 10%.
3
6.42
IDT71321SA/LA and IDT71421SA/LA
High Speed 2K x 8 Dual-Port Static RAM with Interrupts
Industrial and Commercial Temperature Ranges
DC Electrical Characteristics Over the Operating
Temperature and Supply Voltage Range
(1,4)
(V
CC
= 5.0V ± 10%)
71321X20
71421X20
Com'l Only
Symbol
I
CC
Parameter
Dynamic Operating
Current
(Both Ports Active)
CE
L
and
CE
R
= V
IL
,
Outputs Disabled
f = f
MAX
(2)
Test Condition
Version
COM'L
IND
COM'L
IND
I
SB2
Standby Current
(One Port - TTL
Level Inputs)
CE
"A"
= V
IL
and
CE
"B"
= V
IH
(5)
Active Port Outputs Disabled,
f=f
MAX
(2)
COM'L
IND
COM'L
IND
COM'L
IND
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
Typ.
110
110
____
____
71321X25
71421X25
Com'l
& Ind
Typ.
110
110
110
110
30
30
30
30
65
65
65
65
1.0
0.2
1.0
0.2
60
60
60
60
Max.
220
170
270
220
65
45
75
55
150
115
170
140
15
5
30
10
145
105
165
130
2691 tbl 04a
Max.
250
200
____
____
Unit
mA
I
SB1
Standby Current
(Both Ports - TTL
Level Inputs)
CE
L
and
CE
R
= V
IH
f = f
MAX
(2)
30
30
____
____
65
45
____
____
mA
65
65
____
____
165
125
____
____
mA
I
SB3
Full Standby Current
(Both Ports -
CMOS Level Inputs)
CE
L
and
CE
R
> V
CC
- 0.2V,
V
IN
> V
CC
- 0.2V or
V
IN
< 0.2V, f = 0
(3)
CE
"A"
< 0.2V and
CE
"B"
> V
CC
- 0.2V
(5)
V
IN
> V
CC
- 0.2V or V
IN
< 0.2V
Active Port Outputs Disabled,
f = f
MAX
(2)
1.0
0.2
____
____
15
5
____
____
mA
I
SB4
Full Standby Current
(One Port -
CMOS Level Inputs)
60
60
____
____
155
115
____
____
mA
71321X35
71421X35
Com'l Only
Symbol
I
CC
Parameter
Dynamic Operating
Current
(Both Ports Active)
CE
L
and
CE
R
= V
IL
,
Outputs Disabled
f = f
MAX
(2)
Test Condition
Version
COM'L
IND
COM'L
IND
I
SB2
Standby Current
(One Port - TTL
Level Inputs)
CE
"A"
= V
IL
and
CE
"B"
= V
IH
(5)
Active Port Outputs Disabled,
f=f
MAX
(2)
COM'L
IND
COM'L
IND
COM'L
IND
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
SA
LA
Typ.
80
80
____
____
71321X55
71421X55
Com'l
& Ind
Typ.
65
65
65
65
20
20
20
20
40
40
40
40
1.0
0.2
1.0
0.2
40
40
40
40
Max.
155
110
190
140
65
35
70
50
110
75
125
90
15
4
30
10
100
70
110
85
2691 tbl 04b
Max.
165
120
____
____
Unit
mA
I
SB1
Standby Current
(Both Ports - TTL
Level Inputs)
CE
L
and
CE
R
= V
IH
f = f
MAX
(2)
25
25
____
____
65
45
____
____
mA
50
50
____
____
125
90
____
____
mA
I
SB3
Full Standby Current
(Both Ports -
CMOS Level Inputs)
CE
L
and
CE
R
> V
CC
- 0.2V,
V
IN
> V
CC
- 0.2V or
V
IN
< 0.2V, f = 0
(3)
CE
"A"
< 0.2V and
CE
"B"
> V
CC
- 0.2V
(5)
V
IN
> V
CC
- 0.2V or V
IN
< 0.2V
Active Port Outputs Disabled,
f = f
MAX
(2)
1.0
0.2
____
____
15
4
____
____
mA
I
SB4
Full Standby Current
(One Port -
CMOS Level Inputs)
45
45
____
____
110
85
____
____
mA
NOTES:
1. 'X' in part numbers indicates power rating (SA or LA).
2. At f = f
MAX
, address and control lines (except Output Enable) are cycling at the maximum frequency read cycle of 1/t
RC
, and using “AC TEST CONDITIONS” of input
levels of GND to 3V.
3. f = 0 means no address or control lines change. Applies only to inputs at CMOS level standby.
4. Vcc = 5V, T
A
=+25°C for Typ and is not production tested. Vcc
DC
= 100mA (Typ)
5. Port "A" may be either left or right port. Port "B" is opposite from port "A".
4
6.42
IDT71321SA/LA and IDT71421SA/LA
High Speed 2K x 8 Dual-Port Static RAM with Interrupts
Industrial and Commercial Temperature Ranges
DC Electrical Characteristics Over the Operating
Temperature and Supply Voltage Range (V
CC
= 5.0V ± 10%)
71321SA
71421SA
Symbol
|I
LI
|
|I
LO
|
V
OL
V
OL
V
OH
Parameter
Input Leakage Current
(1)
Output Leakage Current
(1)
Output Low Voltage (I/O
0
-I/O
7
)
Open Drain Output
Low Voltage (BUSY/INT)
Output High Voltage
Test Conditions
V
CC
= 5.5V, V
IN
= 0V to V
CC
CE
= V
IH
, V
OUT
= 0V to V
CC
,
V
CC
- 5.5V
I
OL
= 4mA
I
OL
= 16mA
I
OH
= -4mA
Min.
___
71321LA
71421LA
Min.
___
Max.
10
10
0.4
0.5
___
Max.
5
5
0.4
0.5
___
Unit
µA
µA
V
V
V
2691 tbl 05
___
___
___
___
___
___
2.4
2.4
NOTE:
1. At Vcc < 2.0V leakages are undefined.
Data Retention Characteristics
(LA Version Only)
Symbol
V
DR
I
CCDR
Parameter
V
CC
for Data Retention
Data Retention Current
V
CC
= 2.0V,
CE
> V
CC
- 0.2V
V
IN
> V
CC
- 0.2V or VI
N
< 0.2V
t
CDR
(3)
t
R
(3)
Chip Deselect to Data Retention Time
Operation Recovery Time
COM'L
IND
Test Condition
Min.
2.0
____
Typ.
(1)
____
Max.
0
1500
4000
____
Unit
V
µA
µA
ns
ns
2691 tbl 06
100
100
____
____
0
t
RC
(2)
____
____
NOTES:
1. V
CC
= 2V, T
A
= +25°C, and is not production tested.
2. t
RC
= Read Cycle Time
3. This parameter is guaranteed but not production tested.
Data Retention Waveform
DATA RETENTION MODE
V
CC
4.5V
t
CDR
V
DR
≥
2.0V
4.5V
t
R
CE
V
IH
V
DR
V
IH
2691 drw 04
,
5
6.42
