Texas Instruments JM38510-38301BRA, JM38510-38301B2A, SN54ALS240AJ, SN74ALS240A-1DW, SN74ALS240A-1DWR Datasheet

SN54ALS240A, SN54AS240A, SN74ALS240A, SN74AS240A

OCTAL BUFFERS/DRIVERS

WITH 3-STATE OUTPUTS

SDAS214C – DECEMBER 1982 – REVISED AUGUST 1995

• 3-State Outputs Drive Bus Lines or Buffer

Memory Address Registers

• pnp Inputs Reduce dc Loading

• Package Options Include Plastic

Small-Outline (DW) Packages, Ceramic
Chip Carriers (FK), and Standard Plastic (N)
and Ceramic (J) 300-mil DIPs

description

These octal buffers/drivers are designed
specifically to improve both the performance and
density of 3-state memory address drivers, clock
drivers, and bus-oriented receivers and
transmitters. When these devices are used with
the ′ALS241, ′AS241A, ′ALS244, and ′AS244A,
the circuit designer has a choice of selected
combinations of inverting and noninverting
outputs, symmetrical active-low output-enable
(OE

) inputs, and complementary OE and OE
inputs. These devices feature high fan-out and
improved fan-in.

The -1 version of SN74ALS240A is identical to the
standard version, except that the recommended
maximum I
no -1 version of the SN54ALS240A.

for the -1 version is 48 mA. There is

OL

SN54ALS240A, SN54AS240A ...J PACKAGE

SN74ALS240A, SN74AS240A . . . DW OR N PACKAGE

SN54ALS240A, SN54AS240A . . . FK PACKAGE

1A2
2Y3
1A3
2Y2
1A4

(TOP VIEW)

1OE

1

1A1

2

2Y4

3

1A2

4

2Y3

5

1A3

6

2Y2

7

1A4

8
9

2Y1

GND

10

(TOP VIEW)

2Y4

3 2 1 20 19

4
5
6
7
8

910111213

1A1

20
19
18
17
16
15
14
13
12
11

V

1OE

CC

V
2OE
1Y1
2A4
1Y2
2A3
1Y3
2A2
1Y4
2A1

18
17
16
15
14

CC

1Y1
2A4
1Y2
2A3
1Y3

The SN54ALS240A and SN54AS240A are
characterized for operation over the full military
temperature range of –55°C to 125°C. The
SN74ALS240A and SN74AS240A are
characterized for operation from 0°C to 70°C.

FUNCTION TABLE

(each buffer)

INPUTS

OE A

L H L
L LH

HXZ

OUTPUT

Y

2Y1

GND

2A1

1Y4

2A2 2OE

PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

Copyright  1995, Texas Instruments Incorporated

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SN54ALS240A, SN54AS240A, SN74ALS240A, SN74AS240A
OCTAL BUFFERS/DRIVERS
WITH 3-STATE OUTPUTS

SDAS214C – DECEMBER 1982 – REVISED AUGUST 1995

1

2
4
6
8

19

11
13
15
17

†

EN

EN

logic symbol

1OE

1A1
1A2
1A3
1A4

2OE

2A1
2A2
2A3
2A4

†

This symbol is in accordance with ANSI/IEEE Std 91-1984
and IEC Publication 617-12.

18
16
14
12

logic diagram (positive logic)

1A1

1A2

1A3

1A4

2A1

2A2

1

2

4

6

8

19

11

13

18

16

14

12

1Y1

1Y2

1Y3

1Y4

9

2Y1

7

2Y2

1OE

1Y1
1Y2
1Y3
1Y4

9

2Y1

7

2Y2

5

2Y3

3

2Y4

2OE

2A3

2A4

15

17

5

2Y3

3

2Y4

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)

Supply voltage, V
Input voltage, V

Voltage applied to a disabled 3-state output 5.5 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating free-air temperature range, T

Storage temperature range –65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

‡

Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CC

7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

I

: SN54ALS240A –55°C to 125°C. . . . . . . . . . . . . . . . . . . . . . . . . . .

A

SN74ALS240A 0°C to 70°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

‡

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POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

SN54ALS240A, SN54AS240A, SN74ALS240A, SN74AS240A

UNIT

IOLLow-level output current

mA

PARAMETER

TEST CONDITIONS

UNIT

V

V

OCTAL BUFFERS/DRIVERS

WITH 3-STATE OUTPUTS

SDAS214C – DECEMBER 1982 – REVISED AUGUST 1995

recommended operating conditions

SN54ALS240A SN74ALS240A

MIN NOM MAX MIN NOM MAX

V

CC

V

IH

V

IL

I

OH

T

A

†

Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V

electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)

†

Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V

‡

All typical values are at VCC = 5 V, TA = 25°C.

§

The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.

Supply voltage 4.5 5 5.5 4.5 5 5.5 V
High-level input voltage 2 2 V
Low-level input voltage 0.7 0.8 V
High-level output current –12 –15 mA

p

Operating free-air temperature –55 125 0 70 °C

SN54ALS240A SN74ALS240A

MIN TYP‡MAX MIN TYP‡MAX

V

IK

OH

V

OL

I

OZH

I

OZL

I

I

I

IH

I

IL

I

O

I

CC

§

VCC = 4.5 V, II = –18 mA –1.2 –1.2 V
VCC = 4.5 V to 5.5 V, IOH = –0.4 mA VCC –2 VCC –2

IOH = –3 mA 2.4 3.2 2.4 3.2

VCC = 4.5 V

VCC = 4.5 V

VCC = 5.5 V, VO = 2.7 V 20 20 µA
VCC = 5.5 V, VO = 0.4 V –20 –20 µA
VCC = 5.5 V, VI = 7 V 0.1 0.1 mA
VCC = 5.5 V, VI = 2.7 V 20 20 µA
VCC = 5.5 V, VI = 0.4 V –0.1 –0.1 mA
VCC = 5.5 V, VO = 2.25 V –20 –112 –30 –112 mA

VCC = 5.5 V

IOH = –12 mA 2
IOH = –15 mA 2
IOL = 12 mA 0.25 0.4 0.25 0.4
IOL = 24 mA 0.35 0.5
IOL = 48 mA

Outputs high 4 11 4 11
Outputs low 13 23 13 23
Outputs disabled 14 25 14 25

†

12 24

48

0.35 0.5

†

V

mA

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

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