Integrated Device Technology Inc IDT71256L120DB, IDT71256L120LB, IDT71256L120PB, IDT71256L120TDB, IDT71256L120YB Datasheet

CMOS STATIC RAM
256K (32K x 8-BIT)

Integrated Device Technology, Inc.

FEATURES:

• High-speed address/chip select time
— Military: 25/30/35/45/55/70/85/100/120/150ns (max.)
— Commercial: 20/25/35/45ns (max.) Low Power only.

• Low-power operation

• Battery Backup operation — 2V data retention

• Produced with advanced high-performance CMOS
technology

• Input and output directly TTL-compatible

• Available in standard 28-pin (300 or 600 mil) ceramic
DIP, 28-pin (600 mil) plastic DIP, 28-pin (300 mil) SOJ
and 32-pin LCC

• Military product compliant to MIL-STD-883, Class B

IDT71256S

IDT71256L

DESCRIPTION:

The IDT71256 is a 262,144-bit high-speed static RAM
organized as 32K x 8. It is fabricated using IDT’s high­performance, high-reliability CMOS technology.

Address access times as fast as 20ns are available with
power consumption of only 350mW (typ.). The circuit also
offers a reduced power standby mode. When CS goes HIGH,

the circuit will automatically go to, and remain in, a low-power
standby mode as long as CS remains HIGH. In the full standby
mode, the low-power device consumes less than 15µW,
typically. This capability provides significant system level
power and cooling savings. The low-power (L) version also
offers a battery backup data retention capability where the
circuit typically consumes only 5µW when operating off a 2V
battery.

The lDT71256 is packaged in a 28-pin (300 or 600 mil)
ceramic DIP, a 28-pin 300 mil J-bend SOlC, and a 28-pin (600
mil) plastic DIP, and 32-pin LCC providing high board-level
packing densities.

The IDT71256 military RAM is manufactured in compliance
with the latest revision of MIL-STD-883, Class B, making it
ideally suited to military temperature applications demanding
the highest level of performance and reliability.

FUNCTIONAL BLOCK DIAGRAM

A

0

ADDRESS

DECODER

A14

I/O 0

INPUT

DATA

CIRCUIT

I/O

7

CS
OE
WE

The IDT logo is a registered trademark of Integrated Device Technology, Inc.

CONTROL

CIRCUIT

262,144 BIT

MEMORY ARRAY

I/O CONTROL

MILITARY AND COMMERCIAL TEMPERATURE RANGES AUGUST 1996

1996 Integrated Device Technology, Inc. DSC-2946/7

7.2

V

CC

GND

2946 drw 01

1

IDT71256 S/L
CMOS STATIC RAM 256K (32K x 8-BIT) MILITARY AND COMMERCIAL TEMPERATURE RANGES

PIN CONFIGURATIONS

A
A

I/O
I/O
I/O

GND

INDEX

A6
A5

A4
A3
A2
A1
A

0

NC

I/O0

CS

CS

(1)

OE

OE

I/O Function

IN Write Data

(1)

1

14

2

12

3

A

7

4

A

6

5

A

5

A

4

A

3

A

2

A

1

A

0
0
1
2

6
7
8
9
10
11
12
13
14

D28-3
P28-1
P28-2
D28-1

SO28-5

28
27
26
25
24

23
22

21
20

I/O

19
18

I/O

17

I/O

16

I/O

15

I/O

2946 drw 02

V

WE
A

A
A
A
OE
A

CS

CC

13
8
9
11

10

7
6
5
4
3

DIP/SOJ

TOP VIEW

TRUTH TABLE

WE

WE

X H X High-Z Standby (ISB)
XVHC X High-Z Standby (ISB1)
H L H High-Z Output Disabled
HLLDOUT Read Data
LLXD

NOTE: 2946 tbl 02

1. H = VIH, L = VIL, X = Don’t Care

ABSOLUTE MAXIMUM RATINGS

Symbol Rating Com’l. Mil. Unit

TERM Terminal Voltage –0.5 to +7.0 –0.5 to +7.0 V

V

with Respect
to GND

A Operating 0 to +70 –55 to +125 °C

7

A

32

4
5
6
7
8
9
10
11
12
13

15 16 17 18 19

1

I/O

A12

2

I/O

14

A

1

L32-1

GND

NC

32 31

NC

WE

VCC

2014

3

I/O4I/O

30

29
28
27
26
25
24
23
22
21

5

13

A

2946 drw 03

I/O

A
A
A

NC

OE

A

CS

I/O
I/O

8
9
11

10

7

6

T

Temperature

BIAS Temperature –55 to +125 –65 to +135 °C

T

Under Bias

STG Storage –55 to +125 –65 to +150 °C

T

Temperature

PT Power Dissipation 1.0 1.0 W

OUT DC Output 50 50 mA

I

Current

NOTE: 2946 tbl 03

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 this
specification is not implied. Exposure to absolute maximum rating con­ditions for extended periods may affect reliability.

32-Pin LCC

TOP VIEW

PIN DESCRIPTIONS

Name Description

A0–A14 Addresses
I/O0–I/O7 Data Input/Output

CS
WE
OE

GND Ground

CC Power

V

Chip Select
Write Enable
Output Enable

CAPACITANCE (TA = +25°C, f = 1.0MHz)

Symbol Parameter

CIN Input Capacitance VIN = 0V 11 pF
C

I/O I/O Capacitance VOUT = 0V 11 pF

NOTE: 2946 tbl 04

1. This parameter is determined by device characterization, but is not
production tested.

2946 tbl 01

7.2 2

(1)

Conditions Max. Unit

IDT71256S/L
CMOS STATIC RAM 256K (32K x 8-BIT) MILITARY AND COMMERCIAL TEMPERATURE RANGES

RECOMMENDED OPERATING
TEMPERATURE AND SUPPLY VOLTAGE

Grade Temperature GND VCC

Military –55°C to +125°C 0V 5.0V ± 10%
Commercial 0°C to +70°C 0V 5.0V ± 10%

2946 tbl 05

DC ELECTRICAL CHARACTERISTICS

(1, 2)

RECOMMENDED DC OPERATING
CONDITIONS

Symbol Parameter Min. Typ. Max. Unit

VCC Supply Voltage 4.5 5.0 5.5 V
GND Supply Voltage 0 0 0 V
VIH Input High Voltage 2.2 — 6.0 V

IL Input Low Voltage –0.5

V

NOTE: 2946 tbl 06

1. VIL (min.) = –3.0V for pulse width less than 20ns, once per cycle.

(1)

— 0.8 V

(VCC = 5.0V ± 10%, VLC = 0.2V, VHC = VCC - 0.2V)

71256S/L20 71256S/L25 71256S/L30 71256S/L35

Symbol Parameter Power Com’l. Mil. Com’l. Mil. Com’l. Mil. Com’l. Mil. Unit

I

CC Dynamic Operating Current S — — — 150 — 145 — 140 mA

CS

≤ V

IL, Outputs Open

VCC = Max., f = fMAX

SB Standby Power Supply S — — — 20 — 20 — 20 mA

I

Current (TTL Level)

CS

≥ V

IH, VCC = Max., L 3 — 3 3 — 3 3 3

Outputs Open, f = fMAX

ISB1 Full Standby Power Supply S — — — 20 — 20 — 20 mA

Current (CMOS Level)

CS

≥ V

HC, VCC = Max., f = 0 L 0.4 — 0.4 1.5 — 1.5 0.4 1.5

(2)

L 135 — 115 130 — 125 105 120

(2)

71256S/L45 71256S/L55 71256S/L70 71256S/L85

(3)

71256S/L100

(3)

Symbol Parameter Power Com’l. Mil. Com’l. Mil. Com’l. Mil. Com’l. Mil. Com'l. Mil. Unit

CC Dynamic Operating Current S — 135 — 135 — 135 — 135 — 135 mA

I

CS

≤ V

IL, Outputs Open

VCC = Max., f = fMAX

SB Standby Power Supply S — 20 — 20 — 20 — 20 — 20 mA

I

(2)

L 100 115 — 115 — 115 — 115 — 115

Current (TTL Level)

CS

≥ V

IH, VCC = Max., L 3 3 — 3 — 3 — 3 — 3

Outputs Open, f = fMAX

(2)

ISB1 Full Standby Power Supply S — 20 — 20 — 20 — 20 — 20 mA

Current (CMOS Level)

CS

≥ V

HC, VCC = Max., f = 0 L 0.4 1.5 — 1.5 — 1.5 — 1.5 — 1.5

NOTES: 2946 tbl 07

1. All values are maximum guaranteed values.

MAX = 1/tRC, all address inputs cycling at fMAX; f = 0 means no address pins are cycling.

2. f

3. Also available: 120 and 150 ns military devices.

7.2 3